132results about How to "Reduce surge voltage" patented technology

A capacitor module in which the structure of a connecting portion is highly resistant against vibration and has a low inductance. The capacitor module includes a plurality of capacitors and a laminate made up of a first wide conductor and a second wide conductor joined in a layered form with an insulation sheet interposed between the first and second wide conductors. The laminate comprises a first flat portion including the plurality of capacitors which are supported thereon and electrically connected thereto, a second flat portion continuously extending from the first flat portion while being bent, and connecting portions formed at ends of the first flat portion and the second flat portion and electrically connected to the exterior.

A switching power supply device includes a full-bridge circuit, a transformer, a rectifier circuit, a filter circuit, a first series connection of a snubber capacitor and a first diode, and a second diode. The full-bridge circuit includes switching elements which are controlled to be driven under phase-shift control. The first series connection is connected in parallel with the smoothing reactor, where one terminal is connected to a terminal on positive side of the rectifier circuit, and the other terminal is connected to an anode of the first diode. A cathode of the first diode is connected to one terminal of the smoothing capacitor which is applied with positive voltage. The second diode is provided between a terminal on negative side of the rectifier circuit and a connecting point of the snubber capacitor and the first diode. A cathode of the second diode is connected to the connecting point.

A power control unit which comprises a plurality of semiconductor elements including a plurality of high-potential side semiconductor elements and a plurality of low-potential side semiconductor elements, and each having a first face and a second face, a collector terminal or an emitter terminal provided on the first face, or an emitter terminal and a gate terminal provided on the first face; a plurality of bus bars electrically connected with at least one of the semiconductor elements, and forming a power module together with the semiconductor elements; a terminal block having signal lines and a resin mold which supports the signal lines; and an engaging portion provided on at least one of the bus bars, and engaging with a portion of the terminal block, and also supporting the terminal block, the signal lines directly connected with the gate electrodes through the engaging portion.

A vehicle drive device includes a motor generator (MG2), a power control unit controlling the motor generator (MG2), and a case housing the motor generator (MG2) and the power control unit. The power control unit includes a first inverter driving the motor generator (MG2) and a voltage converter boosting a power supply voltage to apply the voltage to the first inverter. A reactor L1 which is a component of the voltage converter is disposed such that at least a portion of a core comes into contact with the case for heat exchange. Consequently, the heat is dissipated to the case having a large heat capacity for integral housing, to thereby allow the heat dissipation performance of the reactor (L1) arranged in the limited space to be ensured.

A light-emitting-diode drive circuit for driving n (where n is a natural number equal to or greater than two) light-emitting diodes (LED1 to LEDn) connected in series includes n′ (where n′ is any natural number equal to or greater than two but equal to or less than n; here, n′=n−1) lit-LED number control switches (SW1 to SWn−1). Here, there are n′ ways of turning on only one of the n′ lit-LED number control switches (SW1 to SWn−1) and there are, as corresponding to those n′ ways, n′ ways of lighting different numbers of light-emitting diodes among the n light-emitting diodes (LED1 to LEDn) connected in series.

A switching circuit includes: a transistor having a first electrode, a second electrode and a control electrode; a zener diode; and a capacitor. A connection between the first electrode and the second electrode is capable of temporally switching between a condition state and a non-conduction state by switching a control voltage of the transistor. The zener diode and the capacitor are coupled in series between the first electrode and the control electrode of the transistor. The first electrode is a drain or a collector.

In a semiconductor device, a surge voltage is lowered on turning OFF of a switching element, and output current is reduced on turning ON of the switching element in a non-saturated condition to achieve a reduced amount of self-heating. The semiconductor device can comprise a semiconductor switching element, an overvoltage protection circuit, and a resistance circuit to transmit a control signal for turning the switching element ON and OFF to a control terminal of the switching element. The semiconductor device can further comprise a voltage detecting switch that receives a signal corresponding to a voltage appearing at the output terminal of the switching element on turning OFF of the switching element, and a gate resistor change-over switch that operates according to a voltage of a timing capacitor connected to the output side of the voltage detecting switch to increase a resistance value of the resistance circuit.

The purpose of the present invention is to minimize switching losses of an inverse conversion device. An induction heating device comprises: a plurality of induction heating coils (20) which are positioned in close proximity; a plurality of inverse conversion devices (30) which convert DC voltage into square wave voltage, said devices further comprising capacitors (40) which are serially connected to each of the induction heating coils (20); and a control circuit (15) which controls so as to align the phases of the coil currents which flow through the plurality of induction heating coils (20). The control circuit (15) controls the timing at which the square wave voltage transitions such that an instantaneous value of the square wave voltage when the coil voltage zero-crosses is preserved in either DC voltage or turnover voltage.

A capacitor module in which the structure of a connecting portion is highly resistant against vibration and has a low inductance. The capacitor module includes a plurality of capacitors and a laminate made up of a first wide conductor and a second wide conductor joined in a layered form with an insulation sheet interposed between the first and second wide conductors. The laminate comprises a first flat portion including the plurality of capacitors which are supported thereon and electrically connected thereto, a second flat portion continuously extending from the first flat portion while being bent, and connecting portions formed at ends of the first flat portion and the second flat portion and electrically connected to the exterior.

This cathode for electrochemical reactor comprises a diffusion layer and a catalyst layer.It has bimetallic or multimetallic nanoparticles, dispersed in direct contact with the diffusion layer, at least one of the metals being chromium (Cr) wholly or partly in oxidized form.

A semiconductor device includes first and second assembled bodies (12A, 12B). The first assembled body is provided with a first semiconductor chip, a high voltage bus bar (21) connected to one surface of the first semiconductor chip, a first metal wiring board (24-1) connected to the other surface of the first semiconductor chip with a bonding wire, and a third metal wiring board (24-3) connected to the first metal wiring board. The second assembled body is provided with a second semiconductor chip, a low voltage bus bar (23) connected to one surface of the second semiconductor chip with a bonding wire, a second metal wiring board (24-2) connected to the other surface of the second semiconductor chip, and a fourth metal wiring board (24-4) connected by being returned from an end portion of the second metal wiring board and arranged in parallel to the second metal wiring board. The first assembled body and the second assembled body are arranged in a stacked structure wherein the assembled bodies are being separated. Inductance of a main circuit is reduced by the semiconductor module structure.

The invention discloses an over-voltage over-current protector of electronic and electric equipment. The over-voltage over-current protector of the electronic and electric equipment comprises a power surge protective device SPD I, a surge voltage divider and a power frequency current protector, two ends of the power surge protective device SPDI are respectively connected with a live wire and a null line after a power supply distribution board access port and before a protected equipment port, the surge voltage divider is composed of an electric reactor A, a power surge protective device SPD II and an electric reactor B in a series mode, the electric reactor A at one end of the surge voltage divider is arranged on a live wire after the power surge protective device SPD I, the electric reactor B at the other end is arranged on a null line after the power surge protective device SPD I, and the power frequency current protector is composed of a PTC positive temperature coefficient thermistor, an NTC negative temperature coefficient thermistor and a TVS tube. The over-voltage over-current protector of the electronic and electric equipment has surge over-voltage limit and surge residual voltage division protection functions and power frequency over-voltage and over-current protection functions, enables the equipment fault rate to be reduced and enables the equipment aging speed to be lowered.

A power control unit which comprises a plurality of semiconductor elements including a plurality of high-potential side semiconductor elements and a plurality of low-potential side semiconductor elements, and each having a first face and a second face, a collector terminal or an emitter terminal provided on the first face, or an emitter terminal and a gate terminal provided on the first face; a plurality of bus bars electrically connected with at least one of the semiconductor elements, and forming a power module together with the semiconductor elements; a terminal block having signal lines and a resin mold which supports the signal lines; and an engaging portion provided on at least one of the bus bars, and engaging with a portion of the terminal block, and also supporting the terminal block, the signal lines directly connected with the gate electrodes through the engaging portion.

The invention discloses a high-power electromagnetic surveying transmitter system which comprises a generator set, a three-phase rectification bridge, a filter capacitor, an H type inversion bridge, a booster transformer, a single-phase rectification bridge, a transmitting bridge, an electrode, a temperature detection circuit, a first voltage detection circuit, a second voltage detection circuit, a first current detection circuit, a second current detection circuit, a first central processing unit, a second central processing unit and a transmitting control platform. Transmitting voltage parameter and transmitting current parameter are transferred through communication, and actual transmitting voltage and actual transmitting current are displayed in real time through parameter feedback; transmitting parameters of the transmitting control platform are received to control the transmitting of the transmitting bridge, and transmitting voltage and transmitting current signals are acquired and fed back to the transmitting control platform in real time; the PWM (pulse-width modulation) of the H type inversion bridge is realized to obtain stable and reliable transmitting signals; and the electrode is the signal transmitting port of the system. Thus, the accuracy and response speed of the transmitted waveform are improved.

The purpose of the present invention is to minimize switching losses of an inverter. An induction heating device includes: a plurality of induction heating coils (20) which are disposed adjacent with each other; a plurality of inverters (30), each of which has a capacitor (40) serially connected to each of the induction heating coils (20), and converts a DC voltage into a square wave voltage; and a control circuit (15) which controls so as to align the phase of coil currents flowing though the plurality of the induction heating coils (20), wherein the control circuit (15) controls the timing at which the square wave voltage transitions such that an instantaneous value of the square wave voltage is preserved in either the DC voltage or a turnover voltage, when the coil current zero crosses.

A switching power supply unit providing a DC output comprises a DC power supply; a transformer having a primary winding; a main switching element for connecting in series to the primary winding; and an auxiliary switching element for performing ON / OFF operations in synchronism with or opposite to ON / OFF operations performed by the main switching element; wherein an auxiliary switching element drive winding for generating a voltage turning on / off the auxiliary switching element is disposed in the transformer; and a first impedance circuit including a first resistor, a first capacitor being connected in series with the first impedance circuit, and a differentiating circuit for determining the timing for turning on the auxiliary switching element and the ON time thereof is connected to the auxiliary switching element drive winding.

A semiconductor device (11) having a switching function of being turned on or off according to a voltage (Vge) of a driving signal supplied to a gate thereof is driven by generating a feedback voltage (VFE) based on a time change (dI / dt) of a collector current (Ic) of the semiconductor device (11) and applying the feedback voltage (VFE) as part of the voltage (Vge) of the driving signal when the semiconductor device (11) is switched from on to off.

A turn-off feedback unit (23OFF) of a semiconductor device driving unit generates a feedback voltage as part of a voltage of a drive signal for establishing electrical continuity or disconnection in a bus according to a temporal variation of a collector current of a first semiconductor device (11U) when the first semiconductor device (11U) is turned off from on. A turn-on feedback unit (23ON) generates the feedback voltage according to a commutation current flowing through a free wheeling diode (12D) connected to a second semiconductor device (11D) when the first semiconductor device (11U) is turned on from off.

In a DC power supply including a transformer, for making a semiconductor switch operate with a high frequency, an auxiliary circuit that reduces switching loss and a countermeasure circuit for a surge voltage generated in a rectifier diode are provided. In a DC power supply in which a DC power source 101 and a transformer T are connected via a power conversion circuit and a secondary winding of the transformer T is connected to a load RL via a rectifier diode bridge and a filter circuit to supply power to the load RL, a resonance reactor Lz is provided on an output side of the transformer T, a resonant switch circuit 103 including a parallel circuit of a diode Dz and a semiconductor switch Qz and a resonant capacitor Cz is connected in parallel to the rectifier diode bridge and a snubber circuit including a snubber capacitor Cs, a snubber diode Ds1 and a diode Ds2 for discharge is connected to a serial resonant circuit including the resonance reactor Lz and the resonant capacitor Cz in the resonant switch circuit 103 to absorb a surge voltage.

A serially connected surge suppression optimization device has an input terminal, an output terminal, a plurality of surge suppression units. The surge suppression units are serially mounted between the input terminal and the output terminal. Each surge suppression unit has at least one pair of parallel inductors and a plurality of surge absorption units respectively connected with one end of each of the pair of inductors. The pair of parallel inductors mounted in the surge suppression unit in a pre-stage and the surge suppression unit in a post-stage have different conductance values. Accordingly, the surge suppression optimization device connected in a path from which surges pass can significantly reduce energy of a surge flowing in and a residual surge voltage. The different conductance values of the surge suppression units in a pre-stage and a post-stage smoothen an intruding surge to secure better safety protection without abruptly generating a peak rise.

An output voltage controller for an AC vehicle generator is proposed. The output voltage controller can easily suppress variation in rectified output voltage due to a switching surge without using a slope generation circuit in a voltage adjustment circuit. An excitation circuit that excites a field coil 13 includes a circulation element 31, a semiconductor switch element 33, an inductor 35, and transient voltage absorption means 40. The circulation element 31 is connected in parallel to the field coil 13. The semiconductor switch element 33 is connected in series with the field coil 13 and turned on and off by a voltage adjustment circuit 60. The inductor 35 is connected in series with the field coil 13 and the semiconductor switch element 33. The transient voltage absorption means 40 absorbs a transient voltage generated in the inductor 35 in association with the switching of the semiconductor switch element 33 between ON and OFF.

A capacitor is connected between direct current voltage terminals, and inductance means is connected between one end of the capacitor and one of load terminals. In a case in which the direct current voltage exceeds a set value, voltage at both ends of the capacitor is shared by the first and second switching elements that are not electrically conductive; in a case in which the direct current voltage is below the set value, the first and second switching elements are electrically conductive on a periodic basis or as needed to output reversed-polarity voltage between load terminals; and in a case in which the first and second switching elements are turned off, voltage at both ends of the capacitor restricts voltage applied to both ends of the first and second switching elements, during a period in which the first and second feedback rectifier elements are electrically conductive.

A switching device includes a plurality of semiconductor switching elements coupled in series, a smoothing capacitor, and snubber circuit. Each of the semiconductor switching elements includes a free wheel diode. The smoothing capacitor is coupled in parallel with a direct current power source and the semiconductor switching elements. The smoothing capacitor smoothes an output of the direct current power source and supplies the smoothed output to the semiconductor switching elements. The snubber circuit is coupled between a first connecting point and a second connecting point in parallel with the semiconductor switching elements. An inductance of a first channel provided from the first connecting point to the second connecting point through the smoothing capacitor is equal to or more than 10 times as large as an inductance of a second channel including the semiconductor switching elements and the snubber circuit.

In an AC motor driving circuit from an AC power supply and a DC power supply, a matrix converter and a power conversion circuit are provided. The matrix converter is connected between an output of the AC power supply and an input of the AC motor. In the power conversion circuit, switches back-to-back connected to diodes, and bidirectional switches are series-connected, respectively. Connection junctions between the switches and the bidirectional switches are connected to the input phases of the AC motor, respectively. The other terminal of each switch is connected to one terminal of the DC power supply while the other terminal of each bidirectional switch is connected to the other terminal of the DC power supply. In this manner, the number of switches through which electric power passes at the time of operation is reduced so that loss can be reduced. Accordingly, power conversion efficiency can be improved.

The present invention provides a power module, power converter, and vehicular electric machine system capable of reducing inductance of a peripheral section of an output terminal in a power module, and additionally, reducing a surge voltage. A positive emitter conductor 3 connected to an emitter electrode of a positive power semiconductor element Mpu and an output terminal U are electrically interconnected by using a plurality of aluminum wires 7, a negative collector conductor 4 connected to a collector electrode of a negative power semiconductor element Mnu and the output terminal U are electrically interconnected by using a plurality of aluminum wires 9, and the positive emitter conductor 3 connected to the emitter electrode of the positive power semiconductor element Mpu and the negative collector conductor 4 connected to the collector electrode of the negative power semiconductor element Mnu are further electrically interconnected by using a plurality of aluminum wires 8.

A power semiconductor module including a positive-side switching device and a positive-side diode device which are mounted on a positive-side conductive pattern, and a negative-side switching device and a negative-side diode device which are mounted on an output-side conductive pattern. When an insulating substrate is viewed in plan view, the positive-side diode device and the negative-side diode device are disposed between the positive-side switching device and the negative-side switching device, and the negative-side diode device is disposed closer to the positive-side switching device than the positive-side diode device is.

The invention provides an RCD buffering circuit of a Z-source inverter and a Z-source inverter topology circuit comprising the buffering circuit, and relates to the buffering circuit of the Z-source inverter. The buffering circuit aims to solve the problems that direct-current link voltage of RC, RCD and RCD amplitude limiting type buffering circuits for the Z-source inverter generates a slope, the value of the direct-current link voltage is excessively high, and the loss is large. According to the RCD buffering circuit of the Z-source inverter and the Z-source inverter topology circuit comprising the buffering circuit, a non-inductive resistor and a switch device in a traditional RCD buffering circuit are connected in series and then connected with a fast recovery diode in parallel, and then the whole is connected with a non-inductive capacitor in series and then connected to a direct-current bus side of the Z-source inverter in parallel. The switch device additionally arranged is connected when the Z-source inverter is in a non-direct connection state, and disconnected when the Z-source inverter is in a direct connection state. The problems of the voltage distortion, the excessively high voltage value and the large direct connection loss generated when the traditional buffering circuit is applied to the Z-source inverter can be solved. The buffering circuit is suitable for the Z-source inverter medium and small in power.