Hitachi Automotive Systems, Ltd.

Hitachi, Ltd.

Hitachi Astemo Ltd.

Koichi Yahata

Masashige Tsuji

Yasuo Noto

Yoshio Akaishi

Seiji Funaba

Hiroaki Igarashi

Hiroshi Katayama

Haruki Hamada

Hiroki Shimano

Takashi Fujimoto

Takeshi Ikuyama

Hiroshi Suzuki

Kinya Nakatsu

Ryuichi Saito

Hideyuki Sakamoto

Masaki Shiraishi

Hideyo Suzuki

Kenichiro Nakajima

Hirokazu Matsui

Shinichirou Hida

Yawara Kato

Seigo Yukutake

Keiji Kunii

Tetsuro Tateyama

Satoshi Hiranuma

Tatsuya Hatakeyama

Masayoshi Kashihara

Mitsufumi Iwanaka

Shinichiro Hida

Hideki Homma

Masato Takahashi

Trong Tao Bui

There is provided a gate drive circuit that controls a gate voltage applied to a gate terminal of a switching element and drives the switching element. The gate drive circuit includes an overcurrent detection circuit that detects an overcurrent state based on a value of a current flowing through the switching element. A monitor voltage of a power supply line that is connected to the switching element and supplies power to the switching element is input to the overcurrent detection circuit, and the overcurrent detection circuit detects an overvoltage state when the monitor voltage is equal to or greater than a predetermined threshold value.

Gate drive circuit and power conversion device

There are provided a plurality of drive circuits (U,L) for driving respective plural switching devices constituting upper arms and lower arms, a power supply circuit for supplying a power supply to the plurality of drive circuits, and a discharge circuit for discharging a capacitor. The power supply circuit includes a first transformer (U) for the upper arms, and a second transformer (L) for the lower arms, which include a primary winding connected in parallel to a DC power supply. The first transformer and the second transformer include a secondary winding for supplying a power supply to the drive circuits and for supplying a power supply to a low-voltage circuit (). Each of the first transformer and the second transformer includes a feedback winding for outputting the voltage output to the drive circuits, to a power supply control IC. The discharge circuit () is driven by a power supply supplied from the feedback winding.

Power conversion apparatus

A semiconductor element drive device is provided to solve a problem that because a case of a change in the temperature of the semiconductor element or a current flowing through the semiconductor element is not take into consideration, switching loss and noise cannot be reduced sufficiently. In accordance with input sensing information (temperature T, current I), a timing control unitoutputs a delay signal Q to control timing of driving a current increasing circuitso that a reduction of switching loss of an IGBTis maximized. When the IGBTis in turn-on mode or turn-off mode, the current increasing circuitoutputs a drive signal in response to the delay signal Q delayed by a given time from output of the drive instruction signal P. In this way, the current increasing circuitincreases the current that causes the gate capacitor of the IGBTto be charged/discharged in response to the delay signal Q, thereby increasing a switching speed to reduce switching loss.

Semiconductor element drive device and power conversion apparatus

Even when a large current is intentionally flowed during a high-temperature conduction of a semiconductor element, there is a problem in that an overcurrent state is detected to stop current. In the present invention, an overcurrent detectordetects overcurrent when an input voltage Vin reaches a threshold voltage Vth, and outputs an overcurrent detection signal c to a gate driving unit. On the other hand, when a temperature detection signal a and a current control signal b are input, a transistoris conducted, and the input voltage Vin of the overcurrent detectorbecomes zero. In this case, the input voltage Vin of the overcurrent detectordoes not reach the threshold voltage Vth. Therefore, the output of the drive signal output from the gate driving unitis not stopped. For this reason, a large current can flow in a drain current Ids.

Load driver

Circuit configurations become complicate as a power circuit is expanded, and switching elements are necessarily controlled using invert circuits even when an inverter operates normally. A drive circuitmonitors soundness of a gate power circuit. When a voltage value Pis less than a predetermined threshold, the drive circuit determines that a failure occurs in the gate power circuit, and outputs a signal Pto a controller. After receiving the signal P, the controlleroutputs a signal to a signal line Sto operate a photovoltaic coupler of a power supply circuit. Then, the MOS transistor Tin the battery circuitenters a conduction state. The charges accumulated in the capacitor Care immediately accumulated to the gate electrode of the switching elementto turn on the switching element. In addition, the charges discharged from the capacitor Care charged from the photovoltaic coupler.

Power conversion device

An object of the present invention is to diagnose a state of a voltage divider while performing a normal measurement to improve reliability. A voltage detection apparatus according to the present invention includes: a first resistor for dividing voltage of a detection unit into a first divided voltage value; and a test pattern insertion circuit unit including a second resistor for dividing the first divided voltage value into a second divided voltage value and a switching device, wherein the test pattern insertion circuit unit is connected to an equipotential connection point to the first divided voltage value, and wherein a state of the first resistor is detected based on the second divided voltage value when the switching device is conductive.

Voltage detection apparatus

An inverter drive device includes a drive circuit that outputs a gate voltage signal of a power semiconductor element; and a Zener clamping protection circuit that acquires an emitter electrode side voltage of the power semiconductor element, and, if that voltage is greater than a predetermined voltage value, performs clamping of the gate voltage of the drive circuit after a predetermined time interval has elapsed from the acquisition of the emitter electrode side voltage. The Zener clamping protection circuit includes a latch circuit that, after the emitter electrode side voltage has been acquired, continues the clamping of the gate voltage by the Zener clamping protection circuit during an interval.

Inverter drive device

An inverter device includes an inverter circuit, a control circuit, a first drive circuit, a second drive circuit, first and second photocouplers, and a signal switching part. The signal switching part directly transmits the first and second signals outputted from the first photocoupler and the second photocoupler to the corresponding first and second drive circuits respectively when at least one of the first and second signals is an OFF command.

Inverter device

An electric power converter is provided with a plurality of power-conversion elements; a first control circuit that outputs a first control signal; an electricity storage circuit; a second control circuit that outputs a second control signal when the direct-current power source that supplies electrical power to the first control circuit is not normal; and a drive circuit that outputs drive signals for driving the plurality of power-conversion elements. Each of the power-conversion elements is either a power-conversion element of the upper arm connected to the high-voltage side or a conversion element of the lower arm connected to the low-voltage side. In cases when the voltage of the electricity storage circuit is at a higher predetermined first voltage value, the second control circuit outputs a second control signal so that all the power-conversion elements of the upper arm or the lower arm are turned on and the others are turned off.

Power inverter

A power conversion system according to the present invention includes: an inverter circuit unit that converts a direct current power supplied from a direct current source into an alternating current power, the direct current power being supplied to the inverter circuit through a contactor that conducts and interrupts the direct current; a capacitor that smoothes the direct current power; a discharge circuit unit that is connected to the capacitor in parallel, and that includes a discharge resistor for discharging a charge stored in the capacitor and a switching element for the discharge resistor, being connected in series to the discharge resistor; a voltage detection circuit unit that detects voltage between both terminals of the capacitor; a first discharge control circuit that includes a first microcomputer, and that outputs a control signal to control switching of the switching element for discharging; and a second discharge control circuit that outputs an interruption signal to interrupt the switching element for the discharge resistor.

Electric power conversion system

According to the present invention, an electrical power conversion system includes: a motor; an inverter circuit that outputs three-phase (U-phase, V-phase, W-phase) alternating currents to the motor; a current sensor that detects each of the three-phase alternating currents; and a control circuit that controls the inverter circuit based on a torque command value and values detected by the current sensor, so that the three-phase alternating currents outputted from the inverter circuit are formed as sine waves; and wherein the control circuit includes: a current component extraction unit that, based on the values detected by the current sensor, for each phase, extracts current components superimposed upon each of three-phase alternating currents; and an AC current abnormality detection unit that detects abnormality of an AC current flowing to the motor, based on the phases of the current components for any two phases among the three-phase alternating currents.

Electric power conversion system and electric power conversion device

Connection portions (UP throughWP) to which upper arm control terminals (UU throughUW) are connected are disposed at a first edge portion of a drive circuit board (). And connection portions (UN throughWN to which lower arm control terminals (LU throughLW) are connected are disposed at a second edge portion of the drive circuit board (). Upper arm implementation regions (UP throughWP), lower arm implementation regions (UN throughWN), and a low voltage pattern region () in which photo-couplers (U throughW) are implemented are formed in the board region between these board edge portions. And signal wiring (U) that transmits a control signal from a photo-coupler (U) to an implementation region (UN) is formed in a conductor layer that is a lower layer than the conductor layer in the lower arm implementation region in which the lower arm driver circuit is implemented.

A power inverter comprises a power module connected at least to a rotating electric machine, a gate drive circuit board which supplies switching power to the power module, and a rotating electric machine control circuit board which supplies a signal for controlling the waveform of the switching power to the gate drive circuit board. A noise reduction board is formed on a board different from the rotating electric machine control circuit board. The configuration of the noise reduction board is such that various signals for forming a signal for controlling the waveform of the switching power by means of the rotating electric machine control circuit board are inputted through the noise reduction board to the rotating electric machine control circuit board.

To provide a power converter equipped with a current detector which is small and can carry out highly accurate current detection, in the power converter equipped with a power modulehaving a power controlling semiconductor elementdisposed on the power module basewith a ceramic substrateinterposed, and a control unitfor controlling the operation of the power controlling semiconductor element, a current detectorhaving a magnetic detecting unitwhich is disposed in the detection conductor, electrically connected to the power controlling semiconductor elementand disposed on the power module basewith the ceramic substrateinterposed, and has a magnetic detecting semiconductor elementelectrically connected to the control unitis provided in the power module; and relative distance between the detection conductorand the power module baseis larger than the relative distance between the current detection electrodeand the power module base

Power converter, power system provided with same, and mobile body

The power inverter includes: a case made of a metal; a first power module provided in the case and including a DC terminal and an AC terminal; a second power module provided in the case and including a DC terminal and an AC terminal; and a cooling formation body for decreasing heat generated from the first and second power modules. The first and second power modules are disposed in a manner such that the DC terminals face each other.

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Hitachinaka, Japan

Koichi Yahata