Abstract

A power supply system for an independent system includes a plurality of power supply devices, a plurality of power conversion devices, and a control device, the plurality of power conversion devices are connected in parallel to the independent system, the plurality of power conversion devices are voltage source voltage-controlled, the plurality of power conversion devices convert power supplied from the plurality of power supply devices into alternating current power corresponding to the independent system, the plurality of power conversion devices supply the alternating current power after the conversion to the independent system, the control device controls conversion operations of the power of the plurality of power conversion devices, the control device calculates a plurality of active power command values of the plurality of power conversion devices according to active power required by the independent system, and calculates a plurality of reactive power command values.

IPC Classes  ?

• H02J 3/46 - Controlling the sharing of output between the generators, converters, or transformers
• H02M 1/00 - APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF - Details of apparatus for conversion
• H02M 7/493 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode the static converters being arranged for operation in parallel

Abstract

A phase angle detection system according to one aspect of an embodiment of the present invention detects the phase angle of an electric motor in a drive system equipped with a transmission unit that changes the rotation speed of the electric motor. This phase angle detection system comprises: a first sensor; a second sensor; and an arithmetic processing unit. The first sensor outputs a first signal for detecting at least a specific phase angle of a rotor of the electric motor. The second sensor outputs a second signal that enables the detection of the amount of rotation of an output shaft of the transmission unit. In the arithmetic processing unit, the amount of deviation included in a detection result of the specific phase angle from the first signal is predefined for each rotational direction of the electric motor, and the deviation amount of the first signal determined by the rotational direction of the electric motor, the detection result of the first signal, and the second signal are used to calculate an estimated value of the absolute angle of the rotor of the electric motor.

IPC Classes  ?

• H02P 6/16 - Circuit arrangements for detecting position

Abstract

A drive system according to an aspect of the embodiment includes a first phase estimation unit, a second phase estimation unit, a state determination unit, and a drive control unit. The first phase estimation unit generates a first phase obtained by estimating a phase of a rotor on the basis of an initial phase at a startup stage of the synchronous motor. The second phase estimation unit generates a second phase obtained by estimating the phase of the rotating rotor on the basis of the operation state of the synchronous motor. The state determination unit determines the operation state of the synchronous motor. The drive control unit controls the driving of the synchronous motor by using any one of the first phase and the second phase according to the determination result of the operation state of the synchronous motor. The first phase estimation unit corrects the first phase by using the detection result of the rotor position detected from the start of the startup procedure of the synchronous motor to the successful startup.

IPC Classes  ?

• H02P 21/18 - Estimation of position or speed
• H02P 21/00 - Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
• H02P 21/34 - Arrangements for starting
• H02P 27/06 - Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters

Abstract

A drive equipment includes a transformer, a power converter, and a control system. The transformer is configured with a primary winding and a secondary winding, and a winding of an electric motor is connected to the secondary winding. The power converter causes a current to flow through the primary winding of the transformer. The control system performs constant current control on the power converter during a period of a first stage after startup of the electric motor is instructed, to reduce a variation in a current flowing through the primary winding of the transformer, and controls the power converter through variable voltage variable frequency control of the electric motor in a second stage after the first stage.

IPC Classes  ?

• H02M 3/335 - Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
• H02M 1/00 - APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF - Details of apparatus for conversion
• H02M 1/36 - Means for starting or stopping converters
• H02P 27/06 - Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters

Abstract

Provided is a control device in a power conversion device for photovoltaic power generation connected with solar panels at a DC side, wherein the control device comprises: a modulation rate calculation unit which calculates a modulation rate on the basis of a DC voltage of the DC side of the power conversion device and a system voltage RMS value of an AC side of the power conversion device; a limiter adjustment unit which calculates a lower limit limiter operation value on the basis of a prescribed lower limiter setting value, the system voltage RMS value, and a prescribed rated value in response to the modulation rate calculated by the modulation rate calculation unit; a limiter which updates a DC voltage command lower limit limiter on the basis of the lower limit limiter operation value calculated by the limiter adjustment unit; a maximum power point follow-up control unit which performs a maximum power point follow-up control on the basis of DC power generated by the solar panels to calculate a first DC voltage command value, and determines a second DC voltage command value on the basis of the calculated first DC voltage command value and the DC voltage command lower limit limiter set in the limiter; and an inverter control unit which controls an inverter in the power conversion device on the basis of the second DC voltage command value determined by the maximum power point follow-up control unit.

IPC Classes  ?

• H02M 7/48 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
• G05F 1/67 - Regulating electric power to the maximum power available from a generator, e.g. from solar cell

Abstract

In the present uninterruptible power supply apparatus, in a switching period in which a bypass power feed mode is switched to an inverter power feed mode, a semiconductor switch is turned on, a first electromagnetic contactor is turned off, a second electromagnetic contactor is turned on and, in this state, an inverter is activated to start a lap power feed mode, and the semiconductor switch is turned off to end the lap power feed mode. Accordingly, the lap power feed mode can be completed in a short time to reduce an increase of a terminal-to-terminal voltage of a capacitor and thereby prevent the terminal-to-terminal voltage of the capacitor from exceeding an upper limit voltage.

IPC Classes  ?

• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over

Abstract

Provided is a rolling risk presentation device that can present a rolling risk to an operator in a rolling plant such that countermeasures for suppressing and preventing the occurrence of an alarm are taken prior to rolling. The rolling risk presentation device comprises a system database, an alarm history information classification unit, an occurrence probability calculation unit, and a rolling risk presentation unit. The system database stores alarm history information including alarms generated in the past during rolling. The alarm history information classification unit classifies and organizes the alarm history information, that is stored in the system database, by each type of material to be rolled and product size. The occurrence probability calculation unit statistically calculates the number of occurrences of each alarm classified and organized by the alarm history information classification unit for each type of material to be rolled and product size, and calculates the probability of occurrence of each alarm. The rolling risk presentation unit displays the occurrence probability calculated by the occurrence probability calculation unit for each alarm, and thereby presents, to the operator in the rolling plant and before rolling of the material to be rolled, the rolling risks that may occur during rolling of the material to be rolled.

IPC Classes  ?

• B21B 38/00 - Methods or devices for measuring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product
• B21B 33/00 - Safety devices not otherwise provided for; Breaker blocks; Devices for freeing jammed rolls
• G05B 23/02 - Electric testing or monitoring

Abstract

In the present invention, a first communication line (F1) transmits a control signal (S) from an interface circuit (34) to an n-th drive circuit (GDn) in sequence via a first drive circuit (GD1). A second communication line (F2) transmits a semiconductor switch state detection signal (DS) from the n-th drive circuit (GDn) to the interface circuit (34) in sequence via the first drive circuit (GD1). An i-th drive circuit (GDi) includes a driver for driving an i-th semiconductor switch (SWi) in response to the control signal (S), an abnormality detection circuit for detecting an abnormality of the i-th semiconductor switch (SWi), and first and second notification members (A1, A2). The abnormality detection circuit detects an abnormality of the i-th semiconductor switch (SWi) on the basis of the control signal (S) and an operating state of the i-th semiconductor switch (SWi) and notifies of the detection result by using the first notification member (A1). The abnormality detection circuit generates state detection signals indicating operating states of the i-th to the n-th semiconductor switches (SWi to SWn), detects mismatch between the control signal (S) and the operating states of the i-th to the n-th semiconductor switches (SWi to SWn) on the basis of the control signal (S) and the state detection signals, and notifies of the detection result by using the second notification member (A2).

IPC Classes  ?

• H02H 7/00 - Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from norm
• H02H 3/05 - Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition, with or without subsequent reconnection - Details with means for increasing reliability, e.g. redundancy arrangements
• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over

Abstract

A power supply device according to the embodiment supplies DC power to an electrolytic cell that generates hydrogen through electrolysis. This power supply device comprises: a self-excited power converter including a first output terminal and a second output terminal that outputs a positive voltage with respect to the first output terminal; a reactor serially connected to at least one of the first output terminal and the second output terminal; and a filter circuit connected between an anode and a cathode of the electrolytic cell. The filter circuit is a low-pass filter. The cutoff frequency of the filter circuit is set to be lower than the switching frequency of the power converter.

IPC Classes  ?

• C25B 9/65 - Means for supplying current; Electrode connections; Electric inter-cell connections
• H02M 7/02 - Conversion of ac power input into dc power output without possibility of reversal

Abstract

A drive system of an embodiment includes an initial phase command generation unit, a rotor phase detection unit, and a drive control unit. The initial phase command generation unit generates a phase command value corresponding to an initial phase of a rotor before startup of a synchronous motor. The rotor phase detection unit detects a phase of the rotor and outputs the phase. The drive control unit controls the driving of the synchronous motor by using the phase command value. The initial phase command generation unit adjusts the phase command value to approach the phase of the rotor of a detection result by using the detection result of the phase of the rotor detected before the startup by the rotor phase detection unit.

IPC Classes  ?

• H02P 21/09 - Field phase angle calculation based on rotor voltage equation by adding slip frequency and speed proportional frequency

Abstract

In a mist flow rate measuring apparatus of the present disclosure, in a transparent pipe, a camera executes imaging processing of reflected light, the imaging processing having at least a part of a mist flowing region through which a mist-containing gas flows set as an imaging target region, and acquires imaging information. A mist flow rate calculation unit executes mist flow rate calculation processing based on the imaging information. The mist flow rate calculation processing includes sum value calculation processing of obtaining a luminance sum value, which is a sum of a plurality of luminance values indicated by the imaging information, and flow rate derivation processing of deriving the flow rate of the raw material mist from the luminance sum value.

IPC Classes  ?

• G01F 1/74 - Devices for measuring flow of a fluid or flow of a fluent solid material in suspension in another fluid
• G01F 1/7086 - Measuring the time taken to traverse a fixed distance using optical detecting arrangements

Abstract

The purpose of the present disclosure is to provide an active gas generation device capable of supplying a high-concentration active gas. In an active gas generation device (5) according to the present disclosure, a first number of high-voltage electrode structures (13) are each held inside a holding space (S54) of a corresponding groove (54) among a first number of grooves (54), and a second number of grounding electrode structures (14, 3, 4) are each held inside a holding space (S54) of a corresponding groove (54) among a second number of grooves (54). The first number of high-voltage electrode structures (13) and the second number of grounding electrode structures (14, 3, 4) are alternately disposed in a Y-direction. A first planar region of each of the first number of high-voltage electrode structures (13) and a second planar region of each of the second number of grounding electrode structures (14, 3, 4) face each other with a separation space (S56) therebetween.

IPC Classes  ?

• H05H 1/24 - Generating plasma

Abstract

Provided is a camber control device for a continuous rolling mill, capable of reducing a camber in a tip part of a rolling material and suppressing the occurrence of telescoping of a steel strip coil. In this invention, a tip camber measurement unit calculates a tip camber measurement value at a rolling material tip part on the basis of a meandering amount of the rolling material detected by a meandering amount detector. A camber rectification leveling computation unit calculates a camber rectification leveling amount on the basis of the tip camber measurement value. A tip leveling setting unit sets a tip leveling control length and a tip leveling correction amount for reducing the tip camber for a reduction leveling device of each rolling stand. A reduction leveling control unit adjusts the reduction leveling device to a tip-leveling-correction-amount-added position before the rolling material enters the each rolling stand and adjusts the position of the reduction leveling device in such a manner that the tip leveling correction amount gradually decreases after the rolling length at the each rolling stand has reached the tip leveling control length.

IPC Classes  ?

• B21B 37/58 - Roll-force control; Roll-gap control
• B21B 37/68 - Camber or steering control for strip, sheets or plates, e.g. preventing meandering
• B21B 38/04 - Methods or devices for measuring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product for measuring thickness, width, diameter or other transverse dimensions of the product
• B21C 51/00 - Measuring, gauging, indicating, counting, or marking devices specially adapted for use in the production or manipulation of material in accordance with subclasses

Abstract

An assembly jig for a power conversion apparatus, comprising: a pair of fixing portions (11, 15) arranged so as to oppose each other in a first direction orthogonal to an up-down direction; and a supporting member (21) which is provided so as to be attachable from below to a pair of insulating frames (121, 122) fixed to the pair of fixing portions (11, 15) so as to oppose each other in a second direction orthogonal to the up-down direction and first direction and which is for supporting, in the state of being attached to the pair of insulating frames (121, 122), heat dissipation plates and power semiconductor elements that are alternately arranged to be stacked in the first direction between the pair of insulating frames (121, 122), wherein the supporting member (21) comprises a guide portion that, when the heat dissipation plates and power semiconductor elements having been stacked are pressure-welded to each other in the first direction, guides the movements of the heat dissipation plates and power semiconductor elements in the first direction.

IPC Classes  ?

• H01L 23/40 - Mountings or securing means for detachable cooling or heating arrangements
• H01L 25/10 - Assemblies consisting of a plurality of individual semiconductor or other solid state devices all the devices being of a type provided for in the same subgroup of groups , or in a single subclass of , , e.g. assemblies of rectifier diodes the devices having separate containers
• H01L 25/11 - Assemblies consisting of a plurality of individual semiconductor or other solid state devices all the devices being of a type provided for in the same subgroup of groups , or in a single subclass of , , e.g. assemblies of rectifier diodes the devices having separate containers the devices being of a type provided for in group
• H01L 25/18 - Assemblies consisting of a plurality of individual semiconductor or other solid state devices the devices being of types provided for in two or more different subgroups of the same main group of groups , or in a single subclass of ,

Abstract

An overtemperature detecting system according to an embodiment detects a temperature abnormality of a dry-type transformer (hereinafter, referred to as a transformer) cooled by a cooling device. The overtemperature detecting system includes a temperature determining unit. The temperature determining unit determines and outputs a temperature abnormality of the transformer by changing determination conditions of the temperature abnormality of the transformer using operation states during operating and during stopping of the cooling device.

IPC Classes  ?

• H01F 27/08 - Cooling; Ventilating

Abstract

In a mist flow rate measuring apparatus of the present disclosure, an external discharge pipe is constituted of a combination of an upstream pipe, a large-diameter transparent pipe, and a downstream pipe. A part of a mist flowing region in the large-diameter transparent pipe is an imaging target region of a mist imaging camera. An inner diameter D31 of the large-diameter transparent pipe is set to a value larger than an inner diameter D7 of the upstream pipe and an inner diameter D8 of the downstream pipe. That is, the large-diameter transparent pipe, the upstream pipe, and the downstream pipe have a magnitude relationship with respect to the inner diameter of {D31>D7=D8}.

IPC Classes  ?

• G01F 1/7086 - Measuring the time taken to traverse a fixed distance using optical detecting arrangements
• G01F 1/74 - Devices for measuring flow of a fluid or flow of a fluent solid material in suspension in another fluid

Abstract

A design assistance device (2) is configured to comprise: a data acquisition unit (11) for acquiring, as candidate design data for an electric motor, a plurality of pieces of candidate design data that include a plurality of design parameters, and acquiring a first evaluation value for each of the plurality of pieces of candidate design data; and a data generation unit (13) that selects, from among the plurality of pieces of candidate design data acquired by the data acquisition unit (11), some pieces of candidate design data from the first place in the descending order of the first evaluation value as a plurality of pieces of first candidate design data and generates, from the plurality of pieces of first candidate design data, a plurality of pieces of second candidate design data including the plurality of design parameters. In addition, the design assistance device (2) comprises: an evaluation value calculation unit (14) that calculates a second evaluation value for each piece of the first candidate design data on the basis of the plurality of design parameters contained in this piece of the first candidate design data and calculates the second evaluation value for each piece of the second candidate design data on the basis of the plurality of design parameters contained in this piece of the second candidate design data; and a design data selection unit (15) for using the second evaluation values calculated by the evaluation value calculation unit (14) to select, from among the plurality of pieces of first candidate design data and the plurality of pieces of second candidate design data, candidate design data to be used as the design data for the electric motor.

IPC Classes  ?

• G06F 30/20 - Design optimisation, verification or simulation
• G06F 111/06 - Multi-objective optimisation, e.g. Pareto optimisation using simulated annealing [SA], ant colony algorithms or genetic algorithms [GA]

Abstract

The present disclosure provides a low-cost power conversion system that allows for lower loss and less space to be required. The power conversion system comprises: a power converter that converts DC power inputted from a DC power supply to AC power or DC power; a capacitor provided between a positive pole DC line and a negative pole DC line connected to an input terminal of the power converter; a ground line that connects the negative pole DC line and a ground potential and that is provided with a first grounding resistor; a discharge line that connects the positive pole DC line and the ground line on the ground potential side of the first grounding resistor; and a discharge switch that is provided in the discharge line and is turned ON when discharging the residual charge in the capacitor.

IPC Classes  ?

• H02M 7/48 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode

Abstract

The present disclosure relates to a tail end buckling suppression device for a tandem rolling mill rolling a material to be rolled by N (N≥2) successive rolling stands. Each i-th rolling stand (1≤i≤N) of the tandem rolling mill includes an i-th roll bender device screwing down the material to be rolled with preset roll bender pressure. During a period after a tail end of the material to be rolled comes out of one designated j-th rolling stand (1≤j≤N−1) until the tail end of the material to be rolled comes out of the N-th rolling stand, the tail end buckling suppression device causes each of j+1-th to N-th roll bender devices downstream of the j-th rolling stand to continuously lower the roll bender pressure.

IPC Classes  ?

• B21B 37/66 - Roll eccentricity compensation systems
• B21B 31/02 - Rolling stand frames; Roll mountings

Abstract

This electric power conversion control device comprises: an optical fiber; an optical detection part; and a protection control part. The optical fiber is formed to guide light taken in through the side surface of an extending light guide part in the extension direction and to output the light from an end of the light guide part. The optical detection part detects the light guided to the end of the light guide part. When the optical detection part has detected light resulting from an accident accompanied by arc flash, the protection control part halts electric power conversion carried out by an electric power converter relating to the optical fiber.

IPC Classes  ?

• G01R 31/00 - Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere

Abstract

Provided is an EV charging facility comprising: a plurality of charging stands that, by being attachably/detachably connected to EVs, charge power storage devices mounted to the connected EVs; a plurality of power supply circuits that convert power fed from a power system side into DC power corresponding to the EVs and feed the converted DC power to any of the charging stands; a charging and discharging stand that, by being attachably/detachably connected to an EV, charges and discharges a power storage device mounted to the connected EV; and a bidirectional converter that performs bidirectional power conversion in a direction in which the power storage device of the EV connected to the charging and discharging stand is charged and a direction in which the power storage device of the EV connected to the charging and discharging stand is discharged. Accordingly, it is possible to provide an EV charging facility which comprises a plurality of charging stands and which can reduce contracted power with a simpler configuration, and an operation method therefor.

IPC Classes  ?

• H02J 3/46 - Controlling the sharing of output between the generators, converters, or transformers

Abstract

According to one embodiment of the present invention, an inverter apparatus (100) comprises: a power converter (101) for an armature winding; a power converter (102) for a field winding; a velocity control unit (110) which controls three-phase current on dq-axes; a field current control unit (120) which controls field winding current; a simulator (130); and a damper winding failure detection device (200). The damper winding failure detection unit (200) has: a switching unit (210) which switches between a normal operation mode and a failure inspection mode; an inspection current command value generation unit (220) which outputs an AC as a q-axis current command and outputs a DC equivalent value as a d-axis current command in the failure inspection mode; and an inspection time measurement/determination unit (230) which measures a response in a field winding (13) and determines, from a response signal, the presence or absence of anomaly in the damper winding.

IPC Classes  ?

• H02P 23/00 - Arrangements or methods for the control of AC motors characterised by a control method other than vector control
• H02P 6/32 - Arrangements for controlling wound field motors, e.g. motors with exciter coils
• H02P 25/022 - Synchronous motors

Abstract

This electromagnetic wave detection device detects electromagnetic waves from an electromagnetic wave generation source (100) in a first space A in which the electromagnetic wave generation source (100) is disposed and a second space B that is divided by a partitioning plate (200) which attenuates the propagation of electromagnetic waves. The electromagnetic wave detection device comprises an electromagnetic wave observation part (10) comprising a metal wire including: a penetration section (11) that penetrates through a through hole (200A) formed in the partitioning plate (200) while being spaced apart from a peripheral wall of the through hole; a protrusion section (12) that protrudes from the penetration section (11) toward the first space A, and receives electromagnetic waves from the electromagnetic wave generation source (100); and an extension section (13) that extends from the penetration section (11) into the second space B. One end of the electromagnetic wave observation part that is positioned on the second space B side is connected to a ground contact point (300) positioned on the second space B side.

IPC Classes  ?

• G01R 29/08 - Measuring electromagnetic field characteristics
• G01R 31/12 - Testing dielectric strength or breakdown voltage

Abstract

A sub-module of a power conversion device includes: an IGBT, a drive circuit that drives the IGBT, a laminated bus bar on which the IGBT is mounted; a substrate on which the drive circuit is mounted; a housing frame for accommodating the IGBT, the drive circuit, the laminated bus bar, and the substrate; and a separation frame for separating a space in which the drive circuit and the substrate are disposed from a space in which the IGBT and the laminated bus bar are disposed.

IPC Classes  ?

• H02M 7/00 - Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
• H02M 7/5387 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration
• H05K 7/20 - Modifications to facilitate cooling, ventilating, or heating

Abstract

The present disclosure provides a hot rolling mill plate thickness control device capable of reliably threading a tip end portion of material being rolled, without increasing equipment costs, even if the material being rolled is being rolled to be extremely thin. The hot rolling mill plate thickness control device comprises: a plate thickness gauge installed on an exit side of a final rolling stand in a row-arrangement direction; a gap calculating unit for calculating a gap between rolls of each rolling stand, said gap being greater than a product target plate thickness of the material being rolled and corresponding to a threadable plate thickness with which the tip end portion of the material being rolled can be stably threaded; a gap setting unit for setting the gap calculated by the gap calculating unit for each rolling stand; an automatic plate thickness control unit for executing automatic plate thickness control to minimize a plate-thickness deviation between a plate thickness measured value from the plate thickness gauge and the threadable plate thickness; and a target plate thickness changing unit for changing the threadable plate thickness to the product target plate thickness by adding a plate-thickness bias to the plate-thickness deviation with a predetermined ramp rate, after the tip end portion of the material being rolled has been threaded through the final rolling stand.

IPC Classes  ?

• B21B 37/20 - Automatic gauge control in tandem mills

Abstract

This control device comprises: a first action control unit that causes a DC switch to open when a power conversion device is in a standby state and when a first DC voltage value acquired by a voltage acquiring unit has become greater than a predetermined first threshold; a clock unit that, when the DC switch is opened by the first action control unit, clocks the elapsed time after the DC switch has been opened; and a soundness determining unit that when the DC switch is opened while the power conversion device is in the standby mode and when the elapsed time period clocked by the clock unit has reached or exceeded a predetermined first time period, calculates a first differential voltage value that is the difference between the first DC voltage value acquired by the voltage acquiring unit and a second DC voltage value, determines that the DC switch is normal when the first differential voltage value is greater than a predetermined second threshold, and determines that the DC switch is abnormal when the first differential voltage value is equal to or less than the predetermined second threshold.

IPC Classes  ?

• H02H 7/122 - Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from norm for rectifiers for static converters or rectifiers for inverters, i.e. dc/ac converters
• G01R 31/327 - Testing of circuit interrupters, switches or circuit-breakers
• H02J 3/38 - Arrangements for parallelly feeding a single network by two or more generators, converters or transformers

Abstract

The daisy chain communication path of this power conversion system connects a master station that controls a plurality of slave stations each including a power conversion device and the plurality of slave stations to each other. The plurality of slave stations are configured so as to supply power from the power conversion device within each slave station to each load device. The plurality of slave stations switch between "operation" for supplying power from the power conversion devices and "stop" for interrupting the supply of the power to supply the power to the respective load devices. The daisy chain communication path forms a set of a first communication path for sending a control signal α and a second communication path for sending an operation permission signal β. When detecting a communication failure, each of the plurality of slave stations "stops" the supply of power to the power conversion device of a relevant slave station that has detected the communication failure and controls the other slave stations among the plurality of slave stations using the control signal α and the operation permission signal β to "stop" the supply of the power to the power conversion devices of the other slave stations. After that, in a state in which the power supply from each power conversion device is "stopped", the whole or a part of the plurality of slave stations notify, using the control signal α, the master station of information about a failure location in which the failure location is identifiably specified.

IPC Classes  ?

• H02M 7/48 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
• H02M 7/49 - Combination of the output voltage waveforms of a plurality of converters

Abstract

This DC power distribution system comprises a DC bus line (100) distributing DC power, a first power converter (CPL), and a voltage stabilizing device (10). The first power converter (CPL) is connected between the DC bus line (100) and a load and converts the DC power from the DC bus line (100) to the power required by the load. The voltage stabilizing device (10) is connected to the DC bus line (100) in parallel with the first power converter (CPL). The voltage stabilizing device (10) supplies power to the DC bus line (100) in accordance with the variation of an input voltage input from the DC bus line (100) to the first power converter (CPL) and the DC power supplied from the DC bus line (100) to the first power converter (CPL).

IPC Classes  ?

• H02J 1/00 - Circuit arrangements for dc mains or dc distribution networks

Abstract

An uninterruptible power supply system includes: a group of electrical components that constitute the uninterruptible power supply system and are disposed in a first block of the housing; the other group of electrical components that constitute the uninterruptible power supply system and are disposed in a second block of the housing; and a partition structure disposed adjacent to an exhaust side of the second block to adjust an air flow flowing through the first block and the second block.

IPC Classes  ?

• H05K 7/20 - Modifications to facilitate cooling, ventilating, or heating
• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over

Abstract

One direction discharge structure in an active gas generation apparatus satisfies arrangement conditions (a) to (c). The condition (a) is a condition that a region where a corresponding metal electrode and a corresponding metal electrode are overlapped with each other in a plan view serves as a corresponding discharge space in a corresponding gap region. The condition (b) is a condition that the corresponding gap region and a plurality of gas supply holes provided in a corresponding gas supply region are overlapped with each other in a plan view. The condition (c) is a condition that the plurality of gas supply holes provided in the corresponding gas supply region and a plurality of gas ejection holes provided below the corresponding gap region sandwich the corresponding discharge space in a plan view, and are disposed to face each other on a one-to-one basis along a Y direction.

IPC Classes  ?

• H01J 37/32 - Gas-filled discharge tubes

Abstract

A main controller includes a first programmable device, a device, and a first selector. Each controller includes a second programmable device and a second selector. The second programmable device includes a memory and a processor. The first selector connects the first programmable device to a serial communications line when the uninterruptible power supply is in operation. In response to the device receiving an instruction to perform an update process, the first selector connects the device to the serial communications line. The second selector connects the processor to the serial communications line when the uninterruptible power supply is in operation. In response to the processor receiving the instruction to perform the update process from the first programmable device while the uninterruptible power supply is in operation, the second selector connects the memory to the serial communications line.

IPC Classes  ?

• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over
• G06F 1/26 - Power supply means, e.g. regulation thereof

Abstract

In an ultrasonic joining apparatus according to the present disclosure, an ultrasonic joining apparatus control board controls an operation of a lead set unit and a tension adjustment unit including a dancer roller to perform joining tension control processing. The joining tension control processing includes steps of: making a lead wire housing mechanism perform a rewinding driving of rewinding a lead wire in a lead cassette when the dancer roller reaches a lower limit adjustment position in a tension adjustment range; and making the lead wire housing mechanism perform a delivery driving of sending out the lead wire from the lead cassette when the dancer roller reaches an upper limit adjustment position in the tension adjustment range.

IPC Classes  ?

• B23K 20/26 - Auxiliary equipment
• B23K 20/00 - Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating
• B23K 20/10 - Non-electric welding by applying impact or other pressure, with or without the application of heat, e.g. cladding or plating making use of vibrations, e.g. ultrasonic welding

Abstract

This sheet width control device is applicable to a reversing rolling mill that comprises: an edger that has a pair of edger rolls that perform edge rolling on a material being rolled; and a horizontal rolling mill that is disposed downstream of the edger and has a pair of horizontal rolls that perform horizontal rolling on the material being rolled. The sheet width control device comprises a reduction control device, a reduction position detector, a tracking device, and a sheet width actual value calculation device. The reduction control device is configured to cause the edger to operate such that the pair of edger rolls make contact with the material being rolled during reverse pass rolling. The reduction position detector is configured to detect the reduction position of the edger when the pair of edger rolls are in contact with the material being rolled during reverse pass rolling. The tracking device is configured to track the position in the longitudinal direction of the material being rolled during reverse pass rolling. The sheet width actual value calculation device is configured to calculate a sheet width actual value for the material being rolled at a plurality of positions in the longitudinal direction on the basis of the output of the reduction position detector and the output of the tracking device.

IPC Classes  ?

• B21B 38/04 - Methods or devices for measuring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product for measuring thickness, width, diameter or other transverse dimensions of the product
• B21B 37/00 - Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
• B21B 37/22 - Lateral spread control; Width control, e.g. by edge rolling

Abstract

A first current detector detects an output current of a modular uninterruptible power supply apparatus. Each of a plurality of power conversion modules includes a resistive element and a second switch. The second switch connects the first current detector and the resistive element in parallel in an ON state. Each of first control circuits turns on the second switch when setting a corresponding power conversion module to an operating state, and turns off the second switch when setting the power conversion module to a stopped state. Each of the first control circuits detects a shared current of the corresponding power conversion module based on a current flowing through the resistive element when the second switch is in the ON state. Each of the first control circuits controls a power converter such that an output current of the power conversion module matches the shared current.

IPC Classes  ?

• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over
• H02M 1/00 - APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF - Details of apparatus for conversion

Abstract

This method for assisting operation in a rolling line comprises a step for acquiring various data related to a rolled product manufactured on the rolling line. The method comprises: a step for calculating, for each product specification and on the basis of the various data, an occurrence rate of errors occurring in at least one of the quality of a rolled product, the operating status of a rolling line, and operator operations on actuators of the rolling line; and a step for setting, for each product specification and in accordance with how high the occurrence rate is, the manufacturing difficulty of the rolled product. The method further comprises a step for outputting assistance data from an operator terminal to assist an operator who is involved in a manufacturing process of an object to be manufactured on the rolling line, the assistance data comprising, as data on the manufacturing difficulty of the object to be manufactured, data on the manufacturing difficulty of a rolled product having the same product specifications as the product specifications of the object to be manufactured.

IPC Classes  ?

• B21B 37/00 - Control devices or methods specially adapted for metal-rolling mills or the work produced thereby

Abstract

The present disclosure provides a plate thickness control method for a rolling mill whereby it is possible to calculate an appropriate gap correction amount for the rolling mill on the basis of the amount of change in a rolling load between a previous material and a material in question, and to thus improve plate thickness precision. The plate thickness control method for a rolling mill includes: a step in which a rolled coil rolled immediately beforehand by a rolling mill is designated as a previous material, a rolled coil rolled after the previous material is designated as a material in question, the relationship between the amount of change in a rolling load between the previous material and the material in question and the amount of change in a gap error regarding the rolling mill is approximated sequentially by means of a regression model, and a gap error in the rolling of the material in question is predicted on the basis of the regression model; a step in which a gap setting amount in rolling of the material in question is corrected on the basis of the predicted value of the gap error; and a step in which a regression coefficient of the regression model is updated on the basis of the actual rolling load obtained by rolling the material in question and the amount of change in the actual gap error.

IPC Classes  ?

• B21B 37/58 - Roll-force control; Roll-gap control
• B21B 37/20 - Automatic gauge control in tandem mills
• B21B 37/64 - Mill spring or roll spring compensation systems, e.g. control of prestressed mill stands

Abstract

A winding control system according to one embodiment comprises: a motor drive control device that controls the driving of a motor which rotationally drives a mandrel for winding a rolled material around a coil; a tail end sensor that detects one point of the rolled material to thereby output a detection signal indicating that the rolled material passes through a tail end; a winding control device that tracks the position of the tail end; a first camera that is provided between the finishing roll mill and the mandrel and captures images for first image data including information about the shape of the tail end; and an image analysis device that performs image analysis on the first image data at a timing at which the detection signal is emitted, generates a correction value for correcting the position of the tail end on the basis of a result of the image analysis of the image data, and outputs the correction value to the winding control device. The winding control device corrects the position of the tail end by using the correction value.

IPC Classes  ?

• B21C 47/02 - Winding-up or coiling
• B21C 51/00 - Measuring, gauging, indicating, counting, or marking devices specially adapted for use in the production or manipulation of material in accordance with subclasses

Abstract

The power supply device according to an embodiment comprises: a power conversion unit including first input terminals, a first capacitor connected between the first input terminals, a first output terminal that supplies output current to an electromagnet, a first power conversion circuit connected between the capacitor and the output terminal, and first wiring that electrically connects the capacitor and the power conversion circuit to each other; and a control device that controls the power conversion unit on the basis of current command values sequentially supplied from the outside. The control device detects the sequential two maximal current values or sequential two minimal current values of the current command values to estimate the frequency of the output current.

IPC Classes  ?

• H02M 7/48 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode

Abstract

The present disclosure provides a thickness schedule calculation method and a rolling plant that make it possible to calculate and set a limit value for a limit check that is preferable for maintaining a stable rolling and operating state with reduced rolling troubles. The thickness schedule computing method comprises a computing step of computing a thickness schedule by using a rolling model formula including a forward slip model and a rolling load model, on the basis of a rolling load or motor power. The computing step includes a calculating step of calculating at least one of an upper limit value and a lower limit value of the rolling reduction ratio in each rolling stand on the basis of past rolling data, for each product specifications including a steel type category for rolling and a thickness category, and a setting step of setting at least one of the upper limit value and the lower limit value calculated in the calculating step as a limit value for a limit check with respect to the rolling reduction ratio.

IPC Classes  ?

• B21B 37/20 - Automatic gauge control in tandem mills
• B21B 37/00 - Control devices or methods specially adapted for metal-rolling mills or the work produced thereby

Abstract

In the present invention, a command value limiter applies limits to command values which are issued by a host device and which are for charging power and discharging power. A drive signal generator generates a drive signal for an inverter circuit in accordance with a command value for charging power limited by the command value limiter or a command value for discharging power limited by the command value limiter. A PI controller, in response to a direct-current voltage that is applied to the inverter circuit being higher than the working voltage of a charging limiter, calculates a PI control value (a PI control value for limiting charging) for the deviation between the direct-current voltage and the working voltage of the charging limiter and, in response to the direct-current voltage being lower than the working voltage of a discharging limiter, calculates a PI control value (a PI control value for limiting discharging) for the deviation between the direct-current voltage and the working voltage of the discharging limiter. A limiter regulator strengthens limitation of the command value for charging power from the command value limiter in accordance with the PI control value for limiting charging and strengthens limitation of the command value for discharging power from the command value limiter in accordance with the PI control value for limiting discharging.

IPC Classes  ?

• H02J 3/32 - Arrangements for balancing the load in a network by storage of energy using batteries with converting means
• H02M 7/48 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode

Abstract

A power conversion device is connected to a power transmission line which is connected to a generator. The power conversion device includes a frequency detector that detects a system frequency, the system frequency being a frequency of an AC voltage on the power transmission line, a controller that generates a reactive power command value to compensate for a variation in the detected system frequency, and a power converter that outputs reactive power in accordance with the reactive power command value to the power transmission line.

IPC Classes  ?

• H02J 3/16 - Circuit arrangements for ac mains or ac distribution networks for adjusting voltage in ac networks by changing a characteristic of the network load by adjustment of reactive power

Abstract

An insulation diagnosis device according to an embodiment performs insulation diagnosis for a three-phase alternate-current motor on the basis of a U-phase current, a V-phase current, and a W-phase current supplied to the three-phase alternate-current motor, the insulation diagnosis device comprising: a current vector calculation unit (23, 24) that calculates at least one of a zero-phase current vector or a negative-phase current vector on the basis of the U-phase current, the V-phase current, and the W-phase current; a reference current vector storage unit (25) that pre-stores a reference current vector; a current difference vector calculation unit (26) that calculates a current difference vector, which is the difference between the current vector calculated by the current vector calculation unit (23, 24) and the reference current vector; and a determination unit (28) that determines the insulation state of the three-phase alternate-current motor on the basis of the current difference vector.

IPC Classes  ?

• G01R 31/34 - Testing dynamo-electric machines
• G01R 31/12 - Testing dielectric strength or breakdown voltage
• G01R 31/52 - Testing for short-circuits, leakage current or ground faults

Abstract

The present disclosure provides a system for controlling cutting by a crop shear, the system being capable of suppressing cutting errors in a cut material at a set cutting point to the extent possible even if the speed of the cut material varies. This system for controlling cutting by a crop shear, which cuts a cut material being transported on a hot-rolling line, comprises an image detector that detects an image of the cut material being transported, the image detector being disposed on the input side of the crop shear. A tip end position or tail end position of the cut material and the movement amount of the cut material are established from the image data detected by the image detector, and the drive speed of cutting blades of the crop shear is adjusted on the basis of the established tip end position or tail end position and movement amount of the cut material.

IPC Classes  ?

• B23D 36/00 - Control arrangements specially adapted for machines for shearing or similar cutting, or for sawing, stock while the latter is travelling otherwise than in the direction of the cut

Abstract

An AC/DC converter converts an AC voltage supplied from an AC power supply into a first DC power supply voltage. A power supply line transmits the first DC power supply voltage to a plurality of power conversion modules and a bypass module. The bypass module includes a switch connected between the AC power supply and the load, and a first controller that operates upon receiving an operating power supply voltage based on the first DC power supply voltage to thereby control ON/OFF of the switch. Each power conversion module includes a power converter that converts power supplied from the AC power supply or a power storage device into AC power and supplies the AC power to the load, and a second controller that operates upon receiving an operating power supply voltage based on the first DC power supply voltage to thereby control the power converter.

IPC Classes  ?

• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over

Abstract

In the event of power interruption of a commercial AC power source (6), this uninterruptible power supply device: controls a bidirectional chopper (2) such that a DC voltage (VD) between DC lines (L1, L3) becomes a second reference voltage (VDR 2) higher than a first reference voltage (VDR 1) for a prescribed time (Tc); and then controls the bidirectional chopper (2) such that the DC voltage becomes the first reference voltage. Accordingly, during power interruption, a battery current (IB) can be temporarily increased above usual, and even when a small-sized capacitor (C1 to C4) is used, it is possible to prevent the DC voltage from dropping below a lower limit voltage (VDL).

IPC Classes  ?

• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over

Abstract

Provided is a control device of a power conversion device, said power conversion device comprising: at least one alternating-current capacitor that is disposed in a capacitor circuit which branches from an alternating-current circuit on an output side of an inverter, and that is disconnected from the circuit during a failure; and an electric current sensor that is disposed in the capacitor circuit, and that acquires an electric current value of an alternating-current electric current of each phase flowing to the alternating-current capacitor. The control device comprises: an amplitude calculation unit that acquires, from the electric current sensor, the electric current value of the alternating-current electric current of each phase flowing to the alternating-current capacitor, and that calculates, on the basis of the acquired electric current value of the alternating-current electric current of each phase, a value of an amplitude of a fundamental wave component of the alternating-current electric current of each phase; and a failure determination unit that compares the sizes of a prescribed determination value and the value of the amplitude of the fundamental wave component of the alternating-current electric current of each phase calculated by the amplitude calculation unit, and that determines that there is a failure of the alternating-current capacitor if the value of the amplitude of at least one phase among the values of the amplitude of the fundamental wave component of the alternating-current electric current of the phases is less than the prescribed determination value.

IPC Classes  ?

• H02M 7/48 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode

Abstract

The present invention provides a SCADA web HMI system that can prevent delay in updates of display on screens of HMI client machines and stoppage of a server machine even when a processing load on the server machine is large. A SCADA server machine comprises a communication driver and a client management unit that is connected one-to-one with HMI client machines. The client management unit comprises: a reception thread that receives signal data from the communication driver; first and second signal data buffers that can store the signal data, which is received by the reception thread, in association with a signal data identifier for each data type; and a transmission thread that reads signal data stored in the first or second signal data buffer, and transmits the read signal data to an HMI client machine. While the transmission thread is reading signal data from one of the first and second signal data buffers and transmitting the read signal data to an HMI client machine, signal data stored in the other one of the first and second signal data buffers is overwritten.

IPC Classes  ?

• H04L 67/5651 - Reducing the amount or size of exchanged application data
• H04Q 9/00 - Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom

Abstract

A reactive power compensation device includes a power converter and a converter control unit, and compensates reactive power of an AC power grid by output reactive power of the power converter. The converter control unit includes an AC voltage detection unit and an output limit unit. The AC voltage detection unit detects voltage information of the AC power grid to which the power converter is connected. The output limit unit determines whether or not the output reactive power of the power converter needs to be limited, on the basis of the voltage information detected by the AC voltage detection unit, and in a case where the output reactive power needs to be limited, limits the output reactive power of the power converter.

IPC Classes  ?

• H02J 3/18 - Arrangements for adjusting, eliminating or compensating reactive power in networks
• H02M 5/293 - Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases without intermediate conversion into dc by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only

Abstract

A fan unit is disposed on an upper surface of a housing, and includes a fan, a frame member, and a support member. The frame member is disposed to surround an outer circumference of an opening provided in an upper surface of the housing. The support member supports the fan above the opening while being fixed to the frame member. A gap is provided between a lower end of a first surface of the frame member and the upper surface of the housing. A first blocking member is connected to the first surface of the frame member to be slidable in a vertical direction. In a state in which the gap is exposed, at least one second blocking member is inserted through the gap into the frame member to block the opening in the upper surface of the housing.

IPC Classes  ?

• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over
• H02M 7/797 - Conversion of ac power input into dc power output; Conversion of dc power input into ac power output with possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
• H05K 7/20 - Modifications to facilitate cooling, ventilating, or heating

Abstract

A control panel according to an embodiment comprises a housing, an article placement board, and a pull-out mechanism. The front surface of the housing is open. The article placement board is disposed along the front-back direction inside the housing, and has articles attached thereto. The pull-out mechanism pulls out the article placement board in the forward direction while maintaining the orientation thereof when housed inside the housing. The present invention provides a control panel with which it is possible to effectively use the space inside the housing, improve ease of use, and support flexible article placement.

IPC Classes  ?

• H05K 7/18 - Construction of rack or frame
• H02B 1/36 - Racks with withdrawable units

Abstract

This electric power conversion unit is provided with a housing, a plurality of fans, a heat sink, and a plurality of semiconductor elements. The fans cause an air flow inside the housing. The heat sink forms an air flow passageway upstream of an air circulation path inside the housing. The plurality of semiconductor elements are arranged side-by-side along a direction transverse to the air circulation direction of the heat sink on an element arrangement surface of the heat sink.

IPC Classes  ?

• H05K 7/20 - Modifications to facilitate cooling, ventilating, or heating
• H02M 7/48 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode

Abstract

This phase synchronization control circuit (12) comprises: a phase difference detector (20) that detects a phase difference (Δθ) between an AC voltage (VI) and an AC signal (vac); a frequency control unit (21) that generates a first frequency control value (Fc1) such that the phase difference disappears; a frequency limiter (25) that limits the first frequency control value (Fc1) within a variable limit range and generates a second frequency control value (Fc2); a limiter control unit (26) that sets the variable limit range on the basis of the phase difference, and reduces the width of the variable limit range in accordance with a reduction of the phase difference; and an oscillator (28) that generates an AC signal of a frequency that takes a value that corresponds to the second frequency control value. Accordingly, overshoot of the frequency of the AC signal can be kept low.

IPC Classes  ?

• H02M 7/48 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over
• H03L 7/08 - Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop - Details of the phase-locked loop

Abstract

A control apparatus is a control apparatus for a power conversion apparatus including at least one AC capacitor disposed on the output side of an inverter and disconnected from a circuit when the AC capacitor malfunctions and including a current component extractor that acquires current values of the current flowing through the AC capacitor during synchronization control that synchronizes the output voltage from the inverter with a system voltage of a system, the synchronization control performed during activation of the power conversion apparatus with an AC switch on the side facing the system open, and extracts the value of a current component having a frequency synchronized with the frequency of the output voltage from the inverter out of the current values.

IPC Classes  ?

• H02M 7/537 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters
• H02M 1/36 - Means for starting or stopping converters
• H02M 1/32 - Means for protecting converters other than by automatic disconnection

Abstract

A resin producing method is a method of producing a resin with which an insulating structure formed on an outer peripheral portion of a conductor is impregnated. The resin producing method includes a dispersion liquid mixing step of mixing an epoxy resin and a dispersion liquid in which a nanofiller is dispersed in a reactive diluent that reduces a viscosity of the epoxy resin by reacting with the epoxy resin, and a curing agent mixing step of mixing a composition produced by the dispersion liquid mixing step, with a curing agent that cures the epoxy resin. The epoxy resin includes, for example, an alicyclic epoxy resin.

IPC Classes  ?

• C08L 63/00 - Compositions of epoxy resins; Compositions of derivatives of epoxy resins
• C08K 5/06 - Ethers; Acetals; Ketals; Ortho-esters
• C08G 59/42 - Polycarboxylic acids; Anhydrides, halides, or low-molecular-weight esters thereof
• C08K 3/22 - Oxides; Hydroxides of metals
• C08J 5/24 - Impregnating materials with prepolymers which can be polymerised in situ, e.g. manufacture of prepregs
• H01B 3/40 - Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances waxes epoxy resins

Abstract

A rotating electric machine (10) according to an embodiment comprises a housing (13), a bearing (15), and a cylindrical member (17). The bearing (15) rotatably supports a shaft (14) around a rotating central axis (Ax). The cylindrical member (17) has an oil thrower portion (17m) and a seal portion (17n) which are integrally formed. The oil thrower portion (17m) is cylindrically formed around the rotating central axis (Ax), and the shaft (14) is inserted into the inside thereof. The oil thrower portion (17m) is separated from the outer circumferential surface (14a) of the shaft (14) with a first space. The seal portion (17n) is positioned opposite the bearing (15) with respect to the oil thrower portion (17m) and is cylindrically formed around the rotating central axis (Ax). The seal portion (17n) is separated from the outer circumferential surface (14a) with a second space smaller than the first space.

IPC Classes  ?

• H02K 5/173 - Means for supporting bearings, e.g. insulating supports or means for fitting bearings in the bearing-shields using bearings with rolling contact, e.g. ball bearings
• F16C 33/66 - Special parts or details in view of lubrication
• F16C 33/78 - Sealings of ball or roller bearings with a diaphragm, disc, or ring, with or without resilient members

Abstract

An uninterruptible power supply device (100) comprises a compensation power supply circuit (1) and a bypass circuit (20). The bypass circuit is provided electrically in parallel to the compensation power supply circuit. The bypass circuit includes first to third switches (15U-15W) and first to third circuits (17-19). The first to third switches are respectively connected to first to third phases of a three-phase alternating current load. The first to third circuits are respectively provided electrically in parallel to the first to third switches. The first circuit includes a first snubber circuit (17A), a second snubber circuit (17B), and a power line (PL11). The second circuit includes a first snubber circuit (18A), a second snubber circuit (18B), and a power line (PL12). The third circuit includes a first snubber circuit (19A), a second snubber circuit (19B), and a power line (PL13). The respective power lines (PL11, PL12, and PL13) of the first to third circuits are electrically connected to each other.

IPC Classes  ?

• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over
• H02M 7/48 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode

Abstract

A plurality of connection members (10, 20) are connected to an electric apparatus and extend in a first direction perpendicular to a vertical direction. A plurality of terminal members (30, 40) are respectively attached to the plurality of connection members (10, 20) and have a plurality of electric wires respectively connected thereto. The plurality of terminal members (30, 40) respectively include fixing portions (31, 41) and connection portions (32, 42). The fixing portions (31, 41) are attached to the connection members (10, 20) and extend in the first direction. The connection portions (32, 42) are connected to one end portions of the fixing portions (31, 41) in a longitudinal direction and have the electric wires connected thereto. The connection portions (32, 42) extend in a direction orthogonal to the direction in which the fixing portions (31, 41) extend. The plurality of terminal members (30, 40) are respectively attached to the connection members (10, 20) in either a first posture in which the connection portions (32, 42) extend upward in the vertical direction or a second posture in which the connection portions (32, 42) extend downward in the vertical direction.

IPC Classes  ?

• H02B 1/20 - Bus-bar or other wiring layouts, e.g. in cubicles, in switchyards
• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over

Abstract

A rack (110) comprises a first to a fourth column members (11 to 14), and a first and a second guide members (15A, 15B). A casing of an electric device (20) has a first and a second side surfaces in the width direction that are respectively supported by the first and second guide members (15A, 15B). A first and a second regulation members (30A, 30B) are respectively attached to the inner surfaces of the first and second side surfaces of the casing to regulate movement of the casing toward the front of the rack (110). The second regulation member (30B) is opposed and attached to the first regulation member (30A) in the width direction. In a state in which the electric device (20) is housed in the rack (110), the first regulation member (30A) is positioned between the first and third column members (11, 13) in a fore-aft direction. The second regulation member (30B) is positioned between the second and fourth column members (12, 14) in the fore-aft direction.

IPC Classes  ?

• H05K 7/18 - Construction of rack or frame

Abstract

An electric power conversion apparatus of an embodiment includes a DC-side terminal and a heat release member. The heat release member is electrically conductive. The heat release member is provided on the DC-side terminal.

IPC Classes  ?

• H05K 7/20 - Modifications to facilitate cooling, ventilating, or heating
• H02M 7/00 - Conversion of ac power input into dc power output; Conversion of dc power input into ac power output

Abstract

The purpose of the present invention is to obtain an active-gas-generating apparatus that can supply high-concentration active gas from a gas jetting port to a downstream process space. In the active-gas-generating apparatus (51) of the present disclosure, a region in which electrically conductive films for electrodes (31, 41) overlap as seen in plan view within a main dielectric space, which is the space in which a dielectric film for electrodes (30) and a dielectric film for electrodes (40) face each other, is defined as a main discharge space (50). A region including a dielectric through-port (14) and a cover through-port (15) within an auxiliary dielectric space, which is the space in which the dielectric film for electrodes 30 and a shield dielectric film 8 face each other, is defined as an auxiliary discharge space (58). The auxiliary discharge space (58) includes a portion of a buffer space (9) above the shield dielectric film (8), and a path that reaches from the auxiliary discharge space (58) to gas jetting ports (61, 62) is defined as the active gas flow path.

IPC Classes  ?

• H05H 1/24 - Generating plasma

Abstract

This power conversion system control device comprises: a power converter connected to a power source or to a capacitor via wiring; a coil disposed in a position which is around the wiring and at which, when a short circuit failure has occurred because of voltage in the capacitor or in the power source being short-circuited, magnetic fluxes generated by the short circuit failure are interlinked; and a voltage detection circuit for detecting the voltage value of voltage between both ends of the coil. The power conversion system control device further comprises: a voltage acquisition unit for acquiring the voltage value of voltage between both ends of the coil detected by the voltage detection circuit; and a failure detection unit for detecting a short circuit failure of the power converter on the basis of the voltage value acquired by the voltage acquisition unit.

IPC Classes  ?

• H02M 7/48 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode

Abstract

A fan drip-proof structure of an embodiment includes a housing, one or more open-close members, and a regulation member. The housing accommodates a fan. The one or more open-close members open and close a vent port formed on the housing in response to a wind force of an air flow of the fan. The regulation member regulates an open degree of the vent port by the open-close member.

IPC Classes  ?

• F04D 29/46 - Fluid-guiding means, e.g. diffusers adjustable
• F04D 17/08 - Centrifugal pumps

Abstract

According to the present invention, a rolling productivity improvement assistance device for a plant that rolls an iron/non-iron material comprises a data collection unit that collects plant data that includes a production plan, production results, and an operating state from the plant, an indicator calculation unit that, for the plant data acquired by the data collection unit, calculates a productivity, factors for the productivity, and a value for an indicator for each of the factors, a data storage unit that stores the plant data acquired by the data collection unit and indicator data that is data for the values of the indicators calculated by the indicator calculation unit, a productivity evaluation unit that, each time plant data has been gathered, compares the indicators for a productivity to be evaluated with results for the indicators for past productivities to evaluate productivity decline, and a display unit that displays the results of the productivity decline evaluation by the productivity evaluation unit, the productivity that was the basis for the evaluation results, the factors for the productivity, and the value of the indicator for each of the factors.

IPC Classes  ?

• B21B 37/00 - Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
• B21B 38/00 - Methods or devices for measuring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product
• G05B 19/418 - Total factory control, i.e. centrally controlling a plurality of machines, e.g. direct or distributed numerical control (DNC), flexible manufacturing systems (FMS), integrated manufacturing systems (IMS), computer integrated manufacturing (CIM)

Abstract

A power measurement device includes: a first three-phase to two-phase converter converting a three-phase voltage signal of three-phase AC power into a two-phase voltage signal; a second three-phase to two-phase converter converting a three-phase current signal of the three-phase AC power into a two-phase current signal; an instantaneous power calculator calculating an instantaneous value of active power of the three-phase AC power and an instantaneous value of reactive power of the three-phase AC power based on the two-phase voltage signal and the two-phase current signal; a first moving average calculator calculating multiple active power average values of different moving average data quantities; a second moving average calculator calculating multiple reactive power average values of different moving average data quantities; and calculators that calculate average active powers corresponding to a frequency of the three-phase AC power, and the reactive power corresponding to the frequency of the three-phase AC power.

IPC Classes  ?

• G01R 21/133 - Arrangements for measuring electric power or power factor by using digital technique
• G01R 19/25 - Arrangements for measuring currents or voltages or for indicating presence or sign thereof using digital measurement techniques

Abstract

An AC switch that includes a semiconductor switch and a snubber circuit connected in parallel between a first terminal connected to an AC power supply via a circuit breaker and a second terminal connected to a load. The power converter is connected between a power storage device and the second terminal. The current detector detects a current flowing through the AC switch. When the AC power supply is normal, the controller turns on the semiconductor switch. When an open state of the circuit breaker is detected, the controller controls the power converter to supply a current having a phase opposite to that of the current detected by the current detector to flow through the semiconductor switch and supply the AC power to the load. The controller further turns off the semiconductor switch in response to that the amplitude of the current detected by the current detector is 0.

IPC Classes  ?

• H01H 9/54 - Circuit arrangements not adapted to a particular application of the switching device and for which no provision exists elsewhere
• H02M 1/34 - Snubber circuits
• H02M 1/00 - APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF - Details of apparatus for conversion
• H02J 3/38 - Arrangements for parallelly feeding a single network by two or more generators, converters or transformers

Abstract

The purpose of the present invention is to: when a sensor failure occurs during plant operations, provide support by comparing amounts of decrease in production quantity for various possible operational actions and performing guidance display of operation actions which are optimal from the perspective of productivity; and minimize the amount of decrease in production quantity. To accomplish this, this plant operation support system performs a guidance display of provisional action information in a case in which, in a state in which a sensor has failed, the post-provisional action production quantity, for when a provisional action is implemented on the plant and operations are continued in accordance with provisional action information for continuing operations of the plant, is greater than or equal to the post-replacement production quantity, for when restarting operations after work for replacing the failed sensor with a normal sensor is performed.

IPC Classes  ?

• G05B 23/02 - Electric testing or monitoring

Abstract

An object of the present invention is to provide a SCADA web HMI system that can reduce a load for processing input/output signals in a large-scale system. An HMI server apparatus performs three filtering processing. In first filtering processing, in a case where received block data corresponds to a screen currently displayed on a web browser, a set of input/output signals is extracted from the received block data. In second filtering processing, input/output signals each having a value varied from a previous value are extracted from the set of input/output signals extracted in the first filtering processing. In third filtering processing, input/output signals corresponding to display parts arranged in the screen currently displayed on the web browser, are extracted from the input/output signals extracted in the second filtering processing.

IPC Classes  ?

• G06F 9/46 - Multiprogramming arrangements

Abstract

This plate crown control device controls tandem rolling equipment on the basis of an outlet plate crown setting calculation value of each stand as calculated by setting calculation, a mechanical plate crown setting calculation value of each stand, and a bending force and shift position setting value of each stand. A processor calculates a first current learning value on the basis of the difference between a mechanical plate crown observation value and a mechanical plate crown result calculation value. The processor proportionally divides a first learning value by the first current learning value and a smoothing gain and updates the first learning value. The processor, in the next setting calculation and thereafter, calculates the bending force and shift position setting value of each stand by using a corrected mechanical plate crown setting calculation value obtained by adding the first learning value to the mechanical plate crown setting calculation value.

IPC Classes  ?

• B21B 37/38 - Control of flatness or profile during rolling of strip, sheets or plates using roll bending
• B21B 37/28 - Control of flatness or profile during rolling of strip, sheets or plates

Abstract

This load current distribution adjusting device for a storage battery power conversion device comprises: a cross current calculation unit for calculating the cross current of a relevant power conversion device on the basis of an average current of the output currents of a plurality of storage battery power conversion devices performing an autonomous parallel operation and the output current of the relevant power conversion device; a first correction amount calculation unit for calculating a first correction amount of a voltage command value on the basis of the cross current calculated by the cross current calculation unit and the output voltage of the relevant power conversion device; a gain calculation unit for calculating a weighted gain of the relevant power conversion device on the basis of an average voltage of the respective DC voltages of the plurality of storage battery power conversion devices and the DC voltage of the relevant power conversion device; a second correction amount calculation unit for calculating a second correction amount of the voltage command value on the basis of the first correction amount calculated by the first correction amount calculation unit and the weighted gain calculated by the gain calculation unit; and an output current control unit for controlling the output current of the relevant power conversion device on the basis of a predetermined voltage command value and the second correction amount calculated by the second correction amount calculation unit.

IPC Classes  ?

• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• H02J 7/02 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from ac mains by converters
• H02J 7/34 - Parallel operation in networks using both storage and other dc sources, e.g. providing buffering
• H02J 3/46 - Controlling the sharing of output between the generators, converters, or transformers
• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over

Abstract

A partition member is disposed in a space portion between a rear surface of a housing and outer surfaces of a plurality of units. A first partition portion is disposed in a boundary portion between two units adjacent to each other in a vertical direction and extends in a right-left direction. A second partition portion and a third partition portion each are connected to a corresponding one of both ends of the first partition portion in the right-left direction and extend toward the upper surface. Air discharged from a first unit group located above the first partition portion is guided to flow through a first air channel to the upper surface. Air discharged from a second unit group located below the first partition portion is guided to flow through a second air channel to the upper surface.

IPC Classes  ?

• H05K 7/20 - Modifications to facilitate cooling, ventilating, or heating
• H02M 7/00 - Conversion of ac power input into dc power output; Conversion of dc power input into ac power output

Abstract

This uninterruptible power supply apparatus 1 comprises an operation unit (11) for setting a second reference voltage (VBR), a computation unit (21) for establishing a first reference voltage (VDR) that is higher than the set second reference voltage and lower than a maximum value (VDRmax) for the first reference voltage, a first reference voltage generation unit (22) for generating the first reference voltage established by the computation unit, and a second reference voltage generation unit (32) for generating the second reference voltage set by the operation unit. Therefore, the voltage (VD) of a DC line (4) can be reduced below the maximum value for the first reference voltage, and the efficiency of the uninterruptible power supply apparatus 1 can be improved.

IPC Classes  ?

• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over

Abstract

A plurality of semiconductor switches and a mechanical switch are connected in series between a first terminal and a second terminal. A plurality of voltage detectors are provided corresponding to the plurality of semiconductor switches, respectively, and detect terminal-to-terminal voltages of the corresponding semiconductor switches. A plurality of drivers are provided corresponding to the plurality of semiconductor switches, respectively, and turn off the corresponding semiconductor switches in response to control signals from a main controller. Each driver determines whether or not a terminal-to-terminal voltage of the corresponding semiconductor switch matches a terminal-to-terminal voltage of another semiconductor switch of the plurality of semiconductor switches, and outputs a result of determination. The main controller detects a cutoff abnormality in which the plurality of semiconductor switches are not turned off normally, based on the result of determination provided from each of the plurality of drivers.

IPC Classes  ?

• H03K 17/082 - Modifications for protecting switching circuit against overcurrent or overvoltage by feedback from the output to the control circuit

Abstract

An electric-power converter includes a plurality of direct-current power supplies, a plurality of power conversion circuits provided corresponding to the respective direct-current power supplies, an alternating-current power system configured to cause a plurality of alternating-current ends provided in the respective power conversion circuits to be directly connected in parallel through a parallel connection point, and to supply the alternating-current power output from the plurality of alternating-current ends to an alternating-current side through the parallel connection point, a plurality of grounding wires each configured to connect at least two of a plurality of direct-current negative buses between the plurality of direct-current power supplies and the plurality of power conversion circuits, to earth, and a plurality of diodes inserted in series into the respective grounding wires, and each including a cathode side connected to the corresponding direct-current negative bus and an anode side grounded.

IPC Classes  ?

• H02M 7/493 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode the static converters being arranged for operation in parallel
• H02M 1/00 - APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF - Details of apparatus for conversion
• H02H 7/12 - Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from norm for rectifiers for static converters or rectifiers
• H02S 40/32 - Electrical components comprising DC/AC inverter means associated with the PV module itself, e.g. AC modules

Abstract

A detection device according to an embodiment of the present application detects the presence or absence of a workpiece adhered to the inner wall of a drum of a mill for crushing minerals. This detection device stores an initial torque detected at a preset initial rotation angle, calculates a maximum torque on the basis of the initial torque, the initial rotation angle, and a rotation angle greater than the initial rotation angle, calculates the ratio of the torque at the rotation angle divided by the maximum torque, compares the ratio to a preset threshold, and determines that there is a workpiece adhered to the inner wall of the drum if the ratio is equal to or greater than the threshold.

IPC Classes  ?

• B02C 17/18 - Disintegrating by tumbling mills, i.e. mills having a container charged with the material to be disintegrated with or without special disintegrating members such as pebbles or balls - Details

Abstract

A power converter includes a power conversion circuit including a direct-current terminal connected to a solar cell panel, and an alternating-current terminal connected to an alternating-current power system, the power conversion circuit being configured to convert direct-current power generated by the solar cell panel into alternating-current power and to supply the alternating-current power to the alternating-current power system; a current detection unit configured to detect a direct current flowing between the solar cell panel and the power converter; and a control circuit including a power generation mode in which the control circuit controls the power conversion circuit to output active power generated from the direct-current power generated by the solar cell panel to the alternating-current power system, and a reactive power compensation mode in which the control circuit controls the power conversion circuit to output reactive power to the alternating-current power system, the control circuit being configured to perform mode switching between the power generation mode and the reactive power compensation mode based on a magnitude of the direct current detected by the current detection unit.

IPC Classes  ?

• H02J 3/38 - Arrangements for parallelly feeding a single network by two or more generators, converters or transformers
• H02J 3/46 - Controlling the sharing of output between the generators, converters, or transformers
• H02M 1/00 - APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF - Details of apparatus for conversion
• H02M 1/14 - Arrangements for reducing ripples from dc input or output

Abstract

A connection structure includes a circuit board, an insulating member, a housing, and a conductive wire. The insulating member includes a first portion and a second portion. The first portion is fixed to the circuit board. The second portion faces the first portion. The second portion is fixed to the housing. The housing includes a grounded contact. The conductive wire electrically connects the circuit board and the housing while being wound around the insulating member. A shortest distance along a surface of the housing from a position where the conductive wire and the housing are connected to the contact is shorter than a shortest distance along a surface of the housing from the second portion of the insulating member to the contact.

IPC Classes  ?

• H05K 7/14 - Mounting supporting structure in casing or on frame or rack
• H05K 9/00 - Screening of apparatus or components against electric or magnetic fields
• H05K 1/02 - Printed circuits - Details

Abstract

This SCADA web HMI client device comprises a processor and a memory. The memory stores a user access level, image data of an HMI screen, and screen access right information that are received from a web server. The screen access right information includes an operation access level of the HMI screen and operation possibility of the HMI screen through a web browser. The processor draws the HMI screen on the web browser in an operation possible state when the user access level is equal to or higher than the operation access level and an operation on the HMI screen through the web browser is allowed. The processor draws the HMI screen on the web browser in an operation impossible state when the user access level is lower than the operation access level or the operation on the HMI screen through the web browser is not allowed.

IPC Classes  ?

• G05B 23/02 - Electric testing or monitoring

Abstract

In the present invention, a power converter comprises: an inverter that includes a plurality of switching elements, receives DC voltage from a DC voltage source as an input, converts the received DC voltage to variable-voltage, variable-frequency AC voltage, and outputs the converted AC voltage to a load; a control unit that performs PWM control for driving the plurality of switching elements on or off; and a serial arrangement of a positive-electrode-side capacitor and a negative-electrode-side capacitor connected between a positive electrode and a negative electrode of a DC voltage on the input side of the inverter. The output potential of the inverter has at least: the potential of the positive electrode of the DC voltage source; the potential of the negative electrode; and the potential of the neutral point, which is the connection point between the positive-electrode-side capacitor and the negative-electrode-side capacitor. The control unit includes: a modulation factor calculator that calculates the modulation factor of the inverter on the basis of the DC voltage and an output voltage command value; a gate signal generator that compares the calculated modulation factor and a carrier signal and generates a gate signal necessary for on/off-driving of the switching element for generating a pulse train; and a gate signal allocation unit that adjusts the allocation of the gate signals so that the voltage of the positive-electrode-side capacitor and the voltage of the negative-electrode-side capacitor are balanced.

IPC Classes  ?

• H02M 7/487 - Neutral point clamped inverters

Abstract

According to an embodiment, an electric motor drive device includes an electric motor, a main circuit, a current sensor, and a control unit. The electric motor has a plurality of windings. The main circuit transforms power of an alternating current (AC) power supply into AC power and supplies the AC power to each of the plurality of windings. The current sensor detects a load current flowing through each of the plurality of windings. The control unit controls the main circuit on the basis of a current value detected by the current sensor. The control unit controls an amount of power to be supplied from the main circuit to the electric motor on the basis of an amplitude of the load current associated with detection of an undervoltage state of the AC power supply in a state in which the main circuit uses a conversion rule in which an index value for the amplitude of the load current flowing through the plurality of windings is defined.

IPC Classes  ?

• H02P 21/22 - Current control, e.g. using a current control loop
• H02P 27/08 - Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters with pulse width modulation
• H02P 21/34 - Arrangements for starting

Abstract

A bidirectional chopper selectively performs a charging operation and a discharging operation, the charging operation being an operation in which a part of DC power generated by a converter is stored in a power storage device, the discharging operation being an operation in which DC power of the power storage device is supplied to an inverter. A control circuit controls the bidirectional chopper to perform the discharging operation when a power failure of a power system occurs. The control circuit controls the bidirectional chopper based on a system frequency detected by a frequency detector when the power system is normal. The control circuit controls the bidirectional chopper to perform the charging operation in response to an increase in the system frequency, and to perform the discharging operation in response to a decrease in the system frequency.

IPC Classes  ?

• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over

Abstract

This product quality analysis assistance system is applied to a steel plant. In a first process, a plurality of defective waveform patterns determined to be defective in quality are classified into at least one defective waveform pattern group on the basis of similarity. In a second process, a score of correlation with a condition based on product specifications and a process data waveform pattern is calculated for the defective waveform pattern group. In a third process, when the score of correlation indicating characteristics of the defective waveform pattern group is greater than a condition threshold, an input screen including a representative waveform pattern representing the defective waveform pattern group, information according to the score of correlation, and a factor and countermeasure input area is displayed on a monitor.

IPC Classes  ?

• G06Q 50/04 - Manufacturing

Abstract

This SCADA web HMI system draws an HMI screen including a first strip part disposed in a first zone and an extendable second strip part disposed in a second zone. The first strip part and the second strip part are drawn each drawing cycle shorter than the reception cycle of PLC signals. The tip position of the first strip part is calculated each drawing cycle from the time when a first PLC signal is received, on the basis of a transfer speed and an elapsed time included in the first PLC signal. The drawing size of the first strip part is set to the length from the entry side of the first zone to the tip position of the first strip part. Further, if the tip position of the first strip part has not reached the second zone when a second PLC signal is received, the drawing size of the first strip part is set to the zone length of the first zone.

IPC Classes  ?

• G05B 23/02 - Electric testing or monitoring
• B21B 38/00 - Methods or devices for measuring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product

Abstract

In the present invention, a SCADA web HMI system draws an HMI screen including a first rolled part disposed in a first zone and an extensible second rolled part disposed in a second zone. The first rolled part and the second material part are drawn in each drawing period, which is shorter than the PLC signal receiving period. The first rolled part tip position is calculated on the basis of the conveying speed and elapsed time included in the first PLC signal in each drawing period from the time the first PLC signal is received. The size of the drawn first rolled part is set to the length from the entry side of the first zone to the first rolled part tip position. If the first rolled part tip position has not reached the second zone when the second PLC signal has been received, the size of the drawn first rolled part is set to the length of the first zone.

IPC Classes  ?

• G05B 23/02 - Electric testing or monitoring
• B21B 38/00 - Methods or devices for measuring specially adapted for metal-rolling mills, e.g. position detection, inspection of the product

Abstract

The electric motor speed control apparatus in an embodiment comprises a rotation speed estimation unit and a control unit. The rotation speed estimation unit generates an estimated value of a rotation speed of an electric motor by using a result of FFT analysis of a speed detection signal ωFBK, which is based on a detection result from a resolver for detecting the rotation speed of the electric motor, and the speed detection signal ωFBK. The control unit implements speed control so as to reduce deviation between the estimated value of the rotation speed and a speed command value for speed control of the electric motor.

IPC Classes  ?

• G05B 19/4155 - Numerical control (NC), i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by programme execution, i.e. part programme or machine function execution, e.g. selection of a programme

Abstract

A power conversion device includes a first control device to an m-th control device that are capable of communicating with each other. A k-th control device transmits specific information to control devices other than the k-th control device among the first control device to the m-th control device. The specific information includes voltage values of a plurality of unit converters included in a k-th cell set in each of a first arm to a third arm. From each control device other than the k-th control device among the first control device to the m-th control device, the k-th control device receives specific information including the voltage values of the plurality of unit converters. The k-th control device calculates a phase representative value of the voltage values of the plurality of unit converters included in each of the first arm to the third arm.

IPC Classes  ?

• H02M 1/00 - APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF - Details of apparatus for conversion
• H02M 1/084 - Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters using a control circuit common to several phases of a multi-phase system
• H02M 1/12 - Arrangements for reducing harmonics from ac input or output
• H02M 7/483 - Converters with outputs that each can have more than two voltage levels
• H02M 7/5387 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters in a bridge configuration

Abstract

This electric motor control device comprises a signal identification unit and an overvoltage detection unit. The signal identification unit includes an optical isolator for converting electric signals supplied through a terminal to which an external device is connected, and furthermore includes a switch for opening a connection circuit connected to the terminal. The overvoltage detection unit is formed so as to open the switch when the voltage applied to the connection circuit exceeds a threshold voltage.

IPC Classes  ?

• H02P 29/024 - Detecting a fault condition, e.g. short circuit, locked rotor, open circuit or loss of load

Abstract

A control system of a power converter includes a plurality of carrier wave generating units which are respectively provided for a plurality of power converters connected between a plurality of DC power supplies and a common AC power supply and which are configured to respectively generate carrier waves on the basis of an AC voltage of the AC power supply. The control system of the power converter can thereby synchronize carrier phases of a plurality of power converters.

IPC Classes  ?

• H02M 7/493 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode the static converters being arranged for operation in parallel
• H02M 7/537 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only, e.g. single switched pulse inverters

Abstract

Provided is an insulation tape comprising a base layer, two adhesive layers, and two reinforcement layers. The base layer includes a first surface and a second surface on the opposite side of the first surface. The two adhesive layers contain nano-sized silica particles and are overlaid on the first surface and the second surface, respectively. The two reinforcement layers are provided for the first surface and the second surface, respectively, and are adhered to the base layer by the adhesive layers.

IPC Classes  ?

• H02K 3/30 - Windings characterised by the insulating material

Abstract

In the present invention, first and second communication lines (L1, L2) connect, with daisy chains, a plurality of control circuits respectively corresponding to a plurality of UPS modules (U1-U5). The transmission direction of data in the second communication line (L2) is reverse of the transmission direction of data in the first communication line (L1). First communication terminals (Tin1, Tout1) of each of the UPS modules receive, via the first communication line (L1), detection values of AC output currents of the other USP modules and transmit a detection value of an own AC output current to respective other control circuits. Second communication terminals (Tin2, Tout2) of each of the UPS modules receive, via the second communication line (L2), detection values of AC output currents of the other USP modules and transmit a detection value of an own AC output current to the respective other control circuits. The control circuits each generate a current command value on the basis of the detection values of the own AC output currents and the detection values of the AC output currents of the other UPS modules received by the first and/or second communication terminals.

IPC Classes  ?

• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over

Abstract

The SCADA web HMI client device runs a plurality of web browsers communicating with a web server. A first web browser is displayed on first monitor and draws an HMI screen for monitoring and controlling an industrial plant. A second web browser is displayed on a second monitor and draws the HMI screen. An operation right table is obtained from the web server. If, in the operation right table, the first web browser is not permitted to operate the HMI screen, an operation part positioned on the HMI screen of the first web browser is drawn in an inoperable state. If, in the operation right table, the second web browser is permitted to operate the HMI screen, the operation part positioned on the HMI screen of the second web browser is drawn in an operable state.

IPC Classes  ?

• G05B 19/418 - Total factory control, i.e. centrally controlling a plurality of machines, e.g. direct or distributed numerical control (DNC), flexible manufacturing systems (FMS), integrated manufacturing systems (IMS), computer integrated manufacturing (CIM)

Abstract

Provided is an electric power conversion apparatus comprising: a main circuit unit that converts electric power of a distributed power supply into AC power corresponding to an electric power system; and a control unit that controls an operation of the main circuit unit. The control unit has: an estimated value computation unit that computes an estimated value of a resistance component of system impedance of the electric power system, an estimated value of a reactance component of the system impedance, and an estimated value of a voltage value of an infinite busbar power system, on the basis of an active power value at a connection point to the electric power system, a reactive power value at the connection point, and a voltage value at the connection point; and a reactive power computation unit that computes a reactive power command value of reactive power that is supplied to the electric power system, on the basis of the respective estimated values. The estimated value computation unit has a first estimation unit that computes the respective estimated values using a Kalman filter corresponding to a nonlinear system, and a second estimation unit that computes the respective estimated values using Newton's method. Thus, an electric power conversion apparatus, a control device, and a distributed power supply system that can more appropriately reduce voltage fluctuations at a connection point of a distributed power supply are provided.

IPC Classes  ?

• H02M 7/48 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
• H02J 3/18 - Arrangements for adjusting, eliminating or compensating reactive power in networks
• H02J 3/38 - Arrangements for parallelly feeding a single network by two or more generators, converters or transformers

Abstract

In an uninterruptible power supply apparatus, AC current, which includes a feedback component having a value corresponding to deviation between terminal-to-terminal voltage of a capacitor and reference voltage, and a feed forward component obtained by multiplying load current by a gain, is passed into a converter such that the terminal-to-terminal voltage of the capacitor becomes the reference voltage. The gain is set to a first gain in an inverter power feed mode and a bypass power feed mode, and the gain is set to a second gain smaller than the first gain in a switching period of switching between the inverter power feed mode and the bypass power feed mode, to prevent the terminal-to-terminal voltage of the capacitor from exceeding an upper limit voltage in a lap power feed mode.

IPC Classes  ?

• H02J 9/06 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over
• H02J 3/00 - Circuit arrangements for ac mains or ac distribution networks
• H02J 9/08 - Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over requiring starting of a prime-mover
• H02M 1/00 - APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF - Details of apparatus for conversion
• H02M 1/14 - Arrangements for reducing ripples from dc input or output
• H02M 1/32 - Means for protecting converters other than by automatic disconnection
• H02M 5/458 - Conversion of ac power input into ac power output, e.g. for change of voltage, for change of frequency, for change of number of phases with intermediate conversion into dc by static converters using discharge tubes or semiconductor devices to convert the intermediate dc into ac using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only

Abstract

A control device is a control device of a power conversion device, and includes a conversion value calculation unit that acquires a current value of a current flowing in an alternating-current capacitor connected to a capacitor circuit in an output circuit on an alternating-current side of an inverter circuit and performs conversion of the current value to obtain a predetermined conversion value, and a failure detection unit that compares the conversion value obtained by the conversion value calculation unit and a predetermined determination value to be used in failure detection to detect a failure of the alternating-current capacitor.

IPC Classes  ?

• H02M 7/53846 - Control circuits
• H02M 1/12 - Arrangements for reducing harmonics from ac input or output
• H02M 1/00 - APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF - Details of apparatus for conversion

Abstract

A frequency detector detects a system frequency from an AC voltage on an AC power line to which a power conditioner performing system interconnection of a distributed power supply is connected. A power converter is configured to inject lead reactive power or delay reactive power into the AC power line. A controller controls reactive power output from the power converter to output the lead reactive power in response to an increase in the system frequency while outputting the delay reactive power in response to a decrease in the system frequency.

IPC Classes  ?

• H02J 3/00 - Circuit arrangements for ac mains or ac distribution networks
• H02J 3/16 - Circuit arrangements for ac mains or ac distribution networks for adjusting voltage in ac networks by changing a characteristic of the network load by adjustment of reactive power

Abstract

Provided is a photovoltaic power generating system comprising: a plurality of solar cell panels; a plurality of power conversion devices which convert DC power supplied from the plurality of solar cell panels into AC power and supply the AC power to electric power systems; and a control device for controlling the operation of the plurality of power conversion devices. The control device has a total output value calculation unit for calculating a total effective power value representing the magnitude of effective power that can be outputted currently from all of the plurality of power conversion devices; a difference calculation unit for calculating a difference between a total upper limit command value and the total effective power value and dividing the difference by the number of the plurality of power conversion devices, thereby calculating a difference for each of the plurality of power conversion devices; and an upper limit command value calculation unit for adding the difference per power conversion device to an effective power value, thereby calculating an individual upper limit command value for each of the plurality of power conversion devices. Accordingly, it is possible to provide a photovoltaic power generating system and a control device which can inhibit excessive lowering of the total value of effective power to be supplied to electric power systems from a plurality of power conversion devices.

IPC Classes  ?

• H02J 3/38 - Arrangements for parallelly feeding a single network by two or more generators, converters or transformers

Abstract

A motor drive system of the embodiment includes a power converter, a state detector, a frequency calculator, a frequency correction command generator, a drive amount limiter, and a speed controller. The power converter drives a motor by PWM control. The state detector detects a drive state of the motor. The frequency calculator detects a size of a specific frequency component which fluctuates according to the drive state by using an index value indicating the drive state. The frequency correction command generator generates a correction command of a carrier frequency used for the PWM control on the basis of a detected result of periodic fluctuation of the drive state. The drive amount limiter limits a drive amount of the motor. The drive amount limiter adjusts an upper limit value of a size of a current caused to flow through windings of the motor in a direction in which the upper limit value is lowered from a predetermined upper limit current value when the carrier frequency is searched for in a direction in which the carrier frequency is increased. The speed controller generates a current reference based on a speed command value and a rotor speed of the motor according to the limitation.

IPC Classes  ?

• H02P 27/08 - Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters with pulse width modulation
• H02P 6/08 - Arrangements for controlling the speed or torque of a single motor

Abstract

Provided is a switching device for charging equipment, the switching device comprising: a switching unit that switches connections between each of a plurality of power sources and each of a plurality of charging stations; and a control unit that controls the switching of connections by the switching unit. The switching unit has a plurality of first switching elements provided to correspond to the plurality of power sources, respectively, and a plurality of second switching elements that are provided between each of the plurality of first switching elements and each of the plurality of charging stations, and allow direct-current power, which is supplied from the plurality of power sources through the plurality of first switching elements, to be selectively supplied to each of the plurality of charging stations. The control unit controls switching of each of the plurality of first switching elements and the plurality of second switching elements, thereby controlling the switching of connections by the switching unit. Thus, provided is the switching device for charging equipment that can appropriately switch output locations while curbing increases in the cost of equipment.

IPC Classes  ?

• H02J 7/00 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• H02J 7/02 - Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from ac mains by converters

Abstract

A discharge unit of an embodiment includes a drain pan, a discharge portion having an insulation property, a grounded drain piping, and a liquid separation part having an insulation property. The drain pan receives a liquid. The discharge portion is connected to the drain pan and drains the liquid remaining in the drain pan. The liquid separation part prevents the liquid from flowing continuously between the discharge portion and the drain piping.

IPC Classes  ?

• H05K 7/20 - Modifications to facilitate cooling, ventilating, or heating
• H02M 1/32 - Means for protecting converters other than by automatic disconnection

Abstract

A power conversion device with a three-level TNPP circuit, includes: a voltage detection unit; a test pulse output unit that outputs a test pulse to an inner switching device connected in a forward direction from the DC neutral point to an AC output terminal when the voltages detected by the voltage detection unit rise and exceed a predetermined threshold; and a determination unit that determines, when the test pulse output unit outputs a test pulse to the inner switching device connected in the forward direction from the DC neutral point to the AC output terminal, upon drop in the voltage between the DC neutral point and the DC negative electrode detected by the voltage detection unit, that an outer switching device connected to the DC negative electrode has a short circuit failure.

IPC Classes  ?

• H02M 7/487 - Neutral point clamped inverters
• H02M 1/32 - Means for protecting converters other than by automatic disconnection

Abstract

Provided is a power supply system for an autonomous system comprising: a plurality of power supply devices; a plurality of voltage-source voltage control power conversion devices that are connected in parallel with an autonomous system, converts the power supplied from the plurality of power supply devices to an AC power corresponding to the autonomous system, and supplies the converted AC power to the autonomous system; and a control device that controls the power conversion operations of the plurality of power conversion devices. The control device calculates the plurality of active power command values of the plurality of power conversion devices according to active powers required in the autonomous system and calculates the plurality of reactive power command values of the plurality of power conversion devices according to reactive powers required in the autonomous system. The plurality of power conversion devices perform voltage control operations so as to output the active powers according to the active power command values and output the reactive powers according to the reactive power command values. This provides the power supply system for the autonomous system capable of stably supplying power to the autonomous system even when the plurality of voltage-source voltage control power conversion devices are operated in parallel.

IPC Classes  ?

• H02M 7/48 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
• H02M 7/493 - Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode the static converters being arranged for operation in parallel