Abstract

This power conversion device is provided with: a voltage detection means for detecting a common-mode voltage generated during a switching operation of a power semiconductor element; a voltage superposition means for superposing the common-mode voltage detected by the voltage detection means on an output of the power conversion device to cancel the common-mode voltage in a frequency equal to or higher than a switching frequency generated during the switching operation of the power semiconductor element; and a residual voltage detection means for detecting the common-mode voltage of the power conversion device superposed by the voltage superposition means. The voltage superposition means includes a feedback means for adding the common-mode voltage detected by the residual voltage detection means and superposing the added result on the output of the power conversion device. The voltage detection means comprises a first choke coil and a first 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

A converter includes a first diode having an anode and a cathode connected respectively to an input terminal and a first output terminal, a second diode having an anode and a cathode connected respectively to a second output terminal and the input terminal, a first transistor connected between the first output terminal and the input terminal, a second transistor connected between the input terminal and the second output terminal, and a bidirectional switch connected between the input terminal and a third output terminal and including third to sixth diodes and a third transistor. Each of the first diode, the second diode, and the third transistor is made of a wide bandgap semiconductor. Each of the first and second transistors and the third to sixth diodes is made of a semiconductor other than the wide bandgap semiconductor.

IPC Classes  ?

• H02M 7/12 - Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
• H02M 7/483 - Converters with outputs that each can have more than two voltage levels

Abstract

A three-dimensional surface potential distribution measurement system for measuring a surface potential of a measurement object comprises: a laser light source; a Pockels crystal exhibiting Pockels effect in which a refractive index changes depending on potential difference between the first end surface and the second end surface; a mirror disposed so as to be attached stationarily to the second end surface of the Pockels crystal; a photodetector to detect a light intensity of the laser light corresponding to the potential difference of the Pockels crystal; a housing that holds those elements; a three-dimensional motion-driver capable of three-dimensionally moving the housing; and a driving controller that controls the three-dimensional motion-driver.

IPC Classes  ?

• G01R 29/08 - Measuring electromagnetic field characteristics
• G01R 31/34 - Testing dynamo-electric machines

Abstract

A power conversion device that converts power by causing a power semiconductor element to perform a switching operation, said power conversion device being equipped with: a voltage detection means that detects a common-mode voltage generated at the time of the switching of the power semiconductor element; a voltage control power supply that generates a voltage of the opposite polarity and the same magnitude as the common-mode voltage by means of a circuit that amplifies the common-mode voltage detected by the voltage detection means; and a voltage superposition means that superposes the voltage generated by the voltage control power supply onto the output from the power conversion device, thereby canceling out common-mode voltage that is equal to or greater than the switching frequency and is generated when the power semiconductor element performs the switching operation.

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

In this uninterruptible power supply device, a first converter (2) for generating direct-current voltage and a second converter (5) for regenerating electric power are separately provided, and bus bars (B1-B3) are used to connect direct-current bus lines (L1-L3) to the second converter (5) and also to a bidirectional chopper (6). The bus bars (B1-B3) are constituted of a laminate bus bar (24), and first semiconductor modules (M1d, M2d) included in the second converter (5) and second semiconductor modules (M1a-M1c, M2a-M2c) included in the bidirectional chopper (6) are mounted on the laminate bus bar (24) and are connected to the bus bars (B1-B3). The bus bars (B1-B3) and the first and second semiconductor modules (M1a-M1d, M2a-M2d) are configured as a single converter unit (7).

IPC Classes  ?

• 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
• 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

This uninterruptible power source device executes counter voltage generation mode between bypass power supply mode and lap power supply mode, performs a voltage feed-forward control with respect to an inverter (2) in accordance with the detection value of a voltage detector (VD5), and generates a counter voltage at one terminal of a switch (S2), said counter voltage being at a level corresponding to the voltage of an output terminal (T4). Consequently, without providing an extra voltage detector for the counter voltage generation, an inrush current can be prevented from flowing from a bypass alternating current power source (52) to an alternating current filter (F2) via the switch (S2) when the switch (S2) is turned on.

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

An uninterruptible power supply device is basically a device that performs a full-time inverter feeding system using a first semiconductor switch, and when a second semiconductor switch, which is an optional item, is connected in parallel to the first semiconductor switch and a full-time bypass feeding system is selected, serves as a device that performs the full-time bypass feeding system using the second semiconductor switch. This leads to a low device cost compared with the case in which an uninterruptible power supply device employing the full-time inverter feeding system and an uninterruptible power supply device employing the full-time feeding system are designed and manufactured separately.

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 converter includes a first diode (D1) having its anode and cathode connected to an input terminal (TO) and a first output terminal (T1), respectively, a second diode (D2) having its anode and cathode connected to a second output terminal (T2) and an input terminal (TO), respectively, and a bidirectional switch connected between the input terminal (TO) and a third output terminal (T3). The bidirectional switch includes third to sixth diodes (D3 to D6) and a transistor (Q1). The first diode (DO, the second diode (D2), and the transistor (Q) are each formed of a wide-bandgap semiconductor, and the third to sixth diodes (D3 to D6) are each formed of a semiconductor other than wide-bandgap semiconductors.

IPC Classes  ?

• H02M 7/12 - Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode

Abstract

A converter includes: a first transistor (Q1) connected between a first output terminal (T1) and an input terminal (T0); a second transistor (Q2) connected between the input terminal (T0) and a second output terminal (T2); first and second diodes (D1, D2) connected in anti-parallel to the first and second transistors (Q1, Q2), respectively; and a bidirectional switch that is connected between the input terminal (T0) and a third output terminal (T3) and that includes third and fourth transistors (Q3, Q4) and third and fourth diodes (D3, D4). The first and second diodes (D1, D2) and the third and fourth transistors (Q3, Q4) each are formed of a wide band gap semiconductor. The third and fourth diodes (D3, D4) and the first and second transistors (Q1, Q2) each are formed of a semiconductor other than the wide band gap semiconductor.

IPC Classes  ?

• H02M 7/12 - Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
• H02M 7/483 - Converters with outputs that each can have more than two voltage levels

Abstract

An inverter includes: a first transistor (Q1) connected between a first input terminal (T1) and an output terminal (T4); a second transistor (Q2) connected between the output terminal (T4) and a second input terminal (T2); first and second diodes (D1, D2) connected in anti-parallel to the first and second transistors (Q1, Q2), respectively; and a bidirectional switch that is connected between a third input terminal (T3) and the output terminal (T4) and that includes third and fourth transistors (Q3, Q4) and third and fourth diodes (D3, D4). The first and second transistors (Q1, Q2) and the third and fourth diodes (D3, D4) are each formed of a wide band gap semiconductor. The third and fourth transistors (Q3, Q4) and the first and second diodes (D1, D2) are each formed of a semiconductor other than the wide band gap semiconductor.

IPC Classes  ?

• H02M 7/483 - Converters with outputs that each can have more than two voltage levels

Abstract

The present invention relates to a three-dimensional surface potential distribution measurement apparatus. Conventionally, electric field relaxation systems in high voltage rotating electrical machines can undesirably discharge heat. The present apparatus has: a laser light source; a Pockels crystal; a mirror; a light detector; a structure supporting these elements while maintaining a positional relationship therebetween; a driver for moving the structure; a driver supporting the test object and rotating it about the longitudinal axis extending in a longitudinal direction of the test object; and a controller for controlling the movement and rotary drivers. The controller coordinates a driving operation by the drivers while maintaining a gap between Pockels crystal's second end face and the test object's surface at a predetermined value such that the second end face of the Pockels crystal approaches all surfaces of the electric field reduction system on the test object.

IPC Classes  ?

• G01R 15/24 - Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using light-modulating devices
• G01R 19/00 - Arrangements for measuring currents or voltages or for indicating presence or sign thereof
• G01R 29/12 - Measuring electrostatic fields

Abstract

A partial discharge measurement device (10) has : an impulse voltage application unit (13); a measurement control unit (20); and first and second partial discharge detection unit (10a, 10b) . The measurement control unit (20) has: a first and a second detector level partial discharge counting unit; and a partial discharge resistance evaluation unit. Each of the first and the second detector level partial discharge counting units outputs a first or second detection signal when the first or second detection signal exceeds a predetermined specified value. The partial discharge resistance evaluation unit counts the number of occurrences of partial discharge based on an output from the first and second detector level partial discharge counting unit, and regards the impulse voltage value at which the count value has reached a predetermined value as a partial discharge inception voltage under the repeated impulse voltage application.

IPC Classes  ?

• G01R 31/12 - Testing dielectric strength or breakdown voltage
• G01R 31/34 - Testing dynamo-electric machines

Abstract

The present invention comprises the following: a three-phase three-level inverter (1); three single-phase five-level inverters (2) which are connected in series to the phase outputs of the three-phase three-level inverter (1); and pulse width control means (8) that for each phase supply a gate pulse to the three-level inverter (1) and to the single-phase five-level inverter (2) of the corresponding phase. A state-transitioning means (84) determines, on the basis of changes in voltage level created by the pulse width control means (8), the output of the switching leg of the three-level inverter (1) and the output of the switching legs outside and inside of the single-phase five-level inverter, and the state-transitioning means makes any of three outputs of the switching legs of the three-level inverter (1) and the outside and inside of the single-phase five-level inverter zero or positive when the voltage level is positive, makes all these three outputs of the legs zero or negative when the voltage level is negative, and makes all these three outputs of the legs zero when the voltage level is zero.

IPC Classes  ?

• H02M 7/483 - Converters with outputs that each can have more than two voltage levels

Abstract

A surface-potential distribution measuring device (1) has: a laser light source (13) ; a Pockels crystal (11) ; a mirror; a photodetector (16) that detects light intensity of the laser beam reflected by the mirror; a holding and mounting part that holds and moves the Pockels crystal (11); a voltage correction database; and a calculation unit that identifies an input voltage corresponding to a testing output voltage as a surface potential of the electric-field-reduction system (3) . The Pockels crystal (11) is formed in such a way that a size of a cross section of the Pockels crystal (11) that is perpendicular to an axial direction changes along the axial direction. The holding and mounting part (30) has a protection unit (31) to protect a structure of the Pockels crystal, a movement unit to (35) that moves the Pockels crystal in order to measure a surface potential of the electric-field-reduction system, and a drive control unit (37) to control the movement unit (35), (36).

IPC Classes  ?

• G01R 31/34 - Testing dynamo-electric machines

Abstract

A power supply system includes a plurality of uninterruptible power supplies provided for a load in parallel. The uninterruptible power supplies each include a power supply unit configured to supply the load with power and being larger in capacitance than the load, and a switch provided between the power supply unit and the load. The power supply system further includes a control unit selecting a first uninterruptible power supply of the plurality of uninterruptible power supplies, and setting the switch of the first uninterruptible power supply to the on state.

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 power conversion circuit connected to a three phase alternating current line is controlled in a PWM system. To control an arm corresponding to each phase, first to third carrier wave signals are generated. The first to third carrier wave signals include two signals having phases, respectively, offset by 180 degrees from each other. This allows a zero phase component to less frequently reach a peak value and be accordingly reduced as time averaged. This can reduce a zero phase harmonic component generated from a power supply apparatus.

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

An impulse voltage generation device (3) uses a predetermined rectangular waveform signal (34) and a high voltage (Va) to generate an impulse voltage (Vain), said high voltage (Va) being obtained by boosting an indicated voltage (Vc) of the rectangular waveform signal (34) on a per-cycle basis. A partial discharge frequency calculation unit (15) receives detection signals (36) based on partial discharges occurring from an object (2) to be measured by the application of the impulse voltage (Vain) and counts the detection signals (36) on a per-cycle basis as a partial discharge frequency. An applied voltage signal observation circuit (12) observes an applied voltage signal (37) indicating the impulse voltage (Vain) applied to the object (2) to be measured. In the first cycle in which the partial discharge frequency reaches a specified frequency or more, a voltage value acquiring unit (13) sets, as a partial discharge starting voltage, the peak value (Va) of the voltage indicated by the applied voltage signal (37) output from the applied voltage signal observation circuit (12). This enables the user to set an arbitrary impulse voltage and reduces user's work.

IPC Classes  ?

• G01R 31/12 - Testing dielectric strength or breakdown voltage

Abstract

A high-voltage generator (13) generates high-voltage HVDC. A signal generator (33) generates a combined signal that is generated only in the period where supply of a pulse signal is effected, by superimposing a period setting signal whereof one cycle includes a pulse supply period and a pulse disabling period, a pulse signal whose frequency is of a higher impulse repetition frequency than the frequency of the period setting signal and whose amplitude represents a voltage value that is lower than the high-voltage HVDC value. A semiconductor switch (40) accumulates charge on a capacitative element (16) by means of the high-voltage HVDC from the high-voltage generator (13) when the voltage value of the combined signal is lower than the set gate voltage value and generates an impulse voltage whose peak value is the value of the high-voltage HVDC, by means of the charge that is discharged from the capacitative element (16) when the voltage value of the combined signal exceeds the set gate voltage value. A test can be carried out in which the period of repetitive generation of stable impulse voltage and the period without generation of impulse voltage are put into effect alternately.

IPC Classes  ?

• H02M 9/04 - Conversion of dc or ac input power into surge output power with dc input power using capacitative stores
• G01R 31/14 - Circuits therefor
• G01R 31/34 - Testing dynamo-electric machines

Abstract

In a surface potential distribution measuring device for an electric field reduction system of a rotating electrical machine, a Pockels crystal is used between a laser and the surface (test location) of the electric field reduction system. Thus, the light intensity of a laser beam reflected on a mirror provided between the Pockels crystal and the test location corresponds to an output voltage that is the voltage difference between the first end surface and the second end surface of the Pockels crystal. Even when an inverter voltage is generated, by using a light detector having a frequency band capable of following the high frequency components of the inverter pulse voltage, the light intensity is detected by the light detector . Therefore, from the light intensity (output voltage) , the surface potential distribution measuring device can measure the surface potential of the electric field reduction system in which an inverter pulse voltage is generated.

IPC Classes  ?

• G01R 31/34 - Testing dynamo-electric machines

Abstract

A property measurement system for a metal material includes: a laser oscillator that emits a pulse laser beam; a lens array that has a plurality of small lenses with a same shape, the small lenses being laid in a matrix on a plane perpendicular to an optical axis of the pulse laser beam, and arranged so that a part of a cross section of the pulse laser beam can be made incident onto each of the plurality of small lenses; a condensing lens that overlaps and condenses emitted beams coming from the plurality of small lenses of the lens array on a same region of a surface of a metal material as a measurement target; a laser interferometer that detects, as an electric signal, a pulse ultrasonic wave that is excited by the pulse laser beam condensed by the condensing lens and propagates through an inside of the metal material; and a signal processing device that processes the electric signal.

IPC Classes  ?

• G01N 29/00 - Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object

Abstract

The present invention is provided with: a pulse laser oscillator (11), which oscillates a first laser beam; a beam splitting unit, which splits the oscillated first laser beam into a plurality of split beams; a plurality of optical paths (12, 13, 14, 15, 16), which propagate the split beams that have been split by the beam splitting unit, and which have different beam propagation times, respectively; a light collecting unit that overlaps and applies the split beams, which have propagated through respective optical paths, to a same position on a material (100) to be measured; a laser interferometer (30), which applies a second laser beam to the material (100), and which detects ultrasonic waves that have been oscillated by the first laser beam and propagated inside of the material (100), on the basis of a beam quantity change generated by having the second laser beam interfere with a reference beam, said second laser beam having been reflected and scattered by the material (100); and a waveform analyzing unit (32), which calculates the metal structure and material of the material (100) on the basis of ultrasonic waves detected by the laser interferometer (30).

IPC Classes  ?

• G01N 29/00 - Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object

Abstract

Wiring between semiconductor modules and a direct current power supply circuit, which construct a three-level power conversion apparatus, is made to be low inductance, so that reduction in size and cost can be attained easily. In cases where a connection is made between direct current power supplies (electrolytic capacitors) 25, 26 and IGBT modules 16 through 18 of a three-level inverter, a wiring conductor for a bi-directional switch part is divided into three conductors 35, 42, 43 or two conductors 35, 42 on a same surface, and these conductors are sandwiched by a P conductor 33 and an N conductor 37, which are arranged at outer sides thereof, respectively, through insulating materials, so that a three-layer wiring structure of a sealed structure is formed. As a result of this, wiring inductance can be made small even with a small number of laminated layers, so that the reduction in size and cost of the apparatus as a whole is achieved.

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 7/04 - Conversion of ac power input into dc power output without possibility of reversal by static converters

Abstract

An uninterruptible power supply system includes a plurality of uninterruptible power supply devices connected in parallel between a commercial AC power supply and a load; and a control unit selecting the required number of uninterruptible power supply devices for driving the load from the plurality of uninterruptible power supply devices, to cause each selected uninterruptible power supply device to be operated and to cause each remaining uninterruptible power supply device to be stopped. This control unit changes the uninterruptible power supply devices to be operated from one to another in a predetermined cycle such that the plurality of uninterruptible power supply devices are identical in operation time to one another. Accordingly, the continuous operation time of each of the uninterruptible power supply devices can be shortened, so that failures occurring in each uninterruptible power supply device can be reduced.

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

An object of the present invention is to provide an ultrasonic bonding tool capable of bonding a lead wire, without any trouble, even to a surface of a thin-film base having a plate thickness of 2 mm or less such as a glass substrate. In the present invention, a surface portion of a chip portion (1c) of an ultrasonic bonding tool (1) used in an ultrasonic bonding apparatus has a plurality of planar portions (10) formed so as to be separated from one another, and a plurality of concavities (11) formed between the plurality of planar portions. Each of the plurality of planar portions (10) has a flatness of 2 µm or less.

IPC Classes  ?

• B06B 1/02 - Processes or apparatus for generating mechanical vibrations of infrasonic, sonic or ultrasonic frequency making use of electrical energy
• 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

Provided is an uninterruptible power supply device including a rectifier circuit rectifying output power of an inverter. At a first startup of the inverter, output power of the rectifier circuit is supplied to an electric double-layer capacitor. At second and subsequent startups of the inverter, output power of one of a converter and the rectifier circuit is selectively supplied to the electric double-layer capacitor. Therefore, by controlling the inverter, the electric double-layer capacitor can be precharged easily with a simple configuration.

IPC Classes  ?

• H02J 15/00 - Systems for storing electric energy

Abstract

In an uninterruptible power supply system, control units of three uninterruptible power supply apparatuses are connected to each another by communication cables to form one total control unit. The total control unit brings three switches into conduction when a bypass power feeding mode is selected by any one operation unit and brings three switches into conduction when an inverter power feeding mode is selected. As such, there is no need to separately provide an operation unit and a control unit for operating and controlling all the uninterruptible power supply apparatuses.

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 an uninterruptible power supply apparatus, a common mode current flowing from nodes (N1 to N3) to a line of a ground voltage (GND) through a stray capacitance of a battery is limited by a common mode reactor, and the low-level common mode current passing through the common mode reactor is caused to flow to a virtual neutral line (NL) through a common mode capacitor. Therefore, the level of noise caused by the common mode current can be reduced.

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 semiconductor stack (1) has a multilayer substrate (2), a plurality of semiconductor modules (3), a plurality of electrolytic capacitors, a plurality of fuses (5) and a cooling fin (6). In the multilayer substrate (2), a P-phase conductor substrate (21), a C-phase conductor substrate (22) and an N-phase conductor substrate overlap each other, with insulating substrates (24b, 24c) in between. The semiconductor modules (3a-3h) are arranged in a row on the rear surface of the multilayer substrate (2). The electrolytic capacitors (4a-4m) are arranged in a row parallel to the row of the semiconductor module on the rear surface of the multilayer substrate (2). The fuses (5a-5m) are arranged on the front surface of the multilayer substrate (2).

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 three-level PWM converter includes first to third fuses having one terminals connected to a DC positive bus, a DC negative bus and a DC neutral point bus, respectively, first and second IGBT elements connected between respective ones of the other terminals of the first and second fuses and an AC line, an AC switch connected between the AC line and the other terminal of the third fuse, first and second diodes connected in anti-parallel to the first and second IGBT elements respectively, a first capacitor connected between the other terminals of the first and third fuses, and a second capacitor connected between the other terminals of the second and third fuses.

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 7/487 - Neutral point clamped inverters
• H02H 7/10 - 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
• 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 7/12 - Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
• H02M 7/219 - Conversion of ac power input into dc 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 in a bridge configuration

Abstract

A housing 2 of an electric power source device 1 has a front face panel 21 having formed therein an air inlet hole 33, a rear face panel 22, two side face panels 23, 24, a bottom plate 25, a top plate 26 having formed therein an air discharge opening 36, and a partition plate 28. The partition plate 28 partitions the space in the housing 2 into a front face-side space 30 and a rear face-side space 31. The partition plate 28 has a front-rear air flow opening 32 for interconnecting the spaces 30, 31. The electric power source device 1 has, in the front face-side space 30, capacitors 56, heat sinks 52 having cooling holes 53 formed therein, semiconductor elements 51 placed on the surfaces of the heat sinks 52. The electric power source device 1 also has an air discharger 81 capable of discharging air in the rear face-side space 31 to the outside of the housing 2, and a guide member 91 for interconnecting the air flow opening 32 and one opening of the cooling hole 53.

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

There is provided a secondary battery system which converts direct current power supplied from secondary batteries (B1 to B3) into alternating current power by power converters (INV1 to INV3), and supplies the converted power to an electric power system on a load side, the secondary battery system including a control apparatus (1) that stops operating the operating the power converter and starts operating the stopped the power converter when a residual stored power level of the secondary battery corresponding to operating the power converter becomes to be not greater than a predetermined rate of a residual stored power level of the secondary battery corresponding to stopped the power converter.

IPC Classes  ?

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

Abstract

An output-power control apparatus is provided in an electric power system connecting a secondary battery system (2) and a power generator (3) in parallel, and controls output power of the electric power system. The output-power control apparatus detects output power of the power generator (3), and controls output voltage of the secondary battery system (2), based on a value obtained by subtracting the detected output power of the power generator (3) from an output power instruction for controlling the output power.

IPC Classes  ?

• H02J 3/32 - Arrangements for balancing the load in a network by storage of energy using batteries with converting means
• H02J 3/38 - Arrangements for parallelly feeding a single network by two or more generators, converters or transformers

Abstract

A power conversion device includes an inverter for converting DC power to AC power to supply the AC power to a load, a converter for converting AC power from an AC power supply to DC power to supply the DC power to the inverter, a DC voltage converter for converting a voltage value of power stored in a storage battery to supply DC power from the storage battery to the inverter when power supply by the AC power supply is abnormal, and a filter which includes a reactor and a capacitor and removes harmonics generated by the inverter. The inverter includes a three-level circuit constituted of an arm and an AC switch.

IPC Classes  ?

• H02M 7/483 - Converters with outputs that each can have more than two voltage levels
• 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 disassembly apparatus of a power generator installed in a nacelle (12) has an I-shaped beam (41), a pressing plate (42), anchor bolts (43), a trolley (44) and a chain block (45). The I-shaped beam (41) extends horizontally above the frame (32) of the power generator. The pressing plate (42) is disposed on the I-shaped beam (41). The anchor bolts extend along both sides of the I-shaped beam to pierce the pressing plate (42) and are screwed into threaded holes extending downward of the frame (32). The trolley (44) is provided movably to roll on the upper surface of the lower flange (47). The chain block is hung from the trolley. The flange (33) removed from the frame (32) is hung and moved vertically by the chain block (45), and is moved horizontally by the trolley (44).

IPC Classes  ?

• H02K 15/02 - Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines of stator or rotor bodies
• B66C 7/08 - Constructional features of runway rails or rail mountings

Abstract

A power conversion apparatus includes an inverter for converting DC power to AC power for supply to a load, a converter for converting AC power from an AC power supply to DC power for supply to the inverter, and a DC voltage converter for converting a voltage value of power stored in a storage battery and supplying DC power from the storage battery to the inverter when power supply by the AC power supply is abnormal. The converter includes a first three-level circuit which is a multi-level circuit. Similarly, the DC voltage converter includes a second three-level circuit. A control device controls the first and second multi-level circuits to suppress potential fluctuation at a neutral point between first and second capacitors.

IPC Classes  ?

• H02M 7/12 - Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
• H02M 7/487 - Neutral point clamped inverters
• H02J 3/38 - Arrangements for parallelly feeding a single network by two or more 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
• H02M 3/155 - Conversion of dc power input into dc power output without intermediate conversion into ac 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 power conversion apparatus includes an inverter for converting DC power to AC power for supply to a load, a converter for converting AC power from an AC power supply to DC power for supply to the inverter, a DC voltage converter for converting a voltage value of power stored in a storage battery to supply DC power from the storage battery to the inverter when power supply from the AC power supply is faulty, and a filter including a reactor and a capacitor, for removing harmonics generated by the inverter. The inverter includes a three-level circuit which is a multi-level circuit.

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 a power conversion device, reactors in an AC input filter absorbing a voltage at a carrier frequency of a PWM converter and reactors in an AC output filter absorbing a voltage at a carrier frequency of a PWM inverter are composed of one six-leg six-phase iron core reactor. Accordingly, the device can be reduced in size when compared with a case where the reactors are composed of two four-leg six-phase iron core reactors.

IPC Classes  ?

• H02M 7/12 - Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode

Abstract

An induction heater device (1) is constituted of a heater portion (2), a plurality of feeder rollers (R) and a leveler portion (3) , and is disposed downstream in regard to a direction of conveyance of the rolled material (P) un-coiled from a coil box (B). The heater portion (2) has an inductor and heats a subject-to-heating material (P) by means of high-frequency induction. The feeder roller (R) conveys the rolled material (P) to the heater portion (2) . The leveler portion (3) is provided in the vicinity of the heater portion (2) and limits a height of a warp of the subject-to-heatingmaterial (P) , thereby improves heating ability of the heater portion (2) substantially and prevents the rolled material (P) from being in contact with the heater portion (2).

IPC Classes  ?

• B21B 45/00 - Devices for surface treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
• B21D 1/00 - Straightening, restoring form or removing local distortions of sheet metal or specific articles made therefrom; Stretching sheet metal combined with rolling
• H05B 6/10 - Induction heating apparatus, other than furnaces, for specific applications

Abstract

In a semiconductor apparatus, a plurality of light-triggered type semiconductor devices, each having a groove for burying of an optical fiber for supplying an optical gate signal to a housing of the light-triggered type semiconductor device, are connected in series. Device cooling heat sinks, each having a flow path for circulating a coolant medium and a coolant inlet and a coolant outlet communicating with the flow path, are disposed on both sides of the housing of each light-triggered type semiconductor device. The light-triggered type semiconductor devices and the device cooling heat sinks are coupled into a single structure. An optical fiber insertion groove, which corresponds in position to the groove of the housing, is provided on a side surface of the device cooling heat sink, which contacts a groove (4)-side surface of the housing of the light-triggered type semiconductor device.

IPC Classes  ?

• H01L 23/473 - Arrangements for cooling, heating, ventilating or temperature compensation involving the transfer of heat by flowing fluids by flowing liquids