Hitachi Automotive Systems, Ltd.

Yasuo Noto

Seiji Funaba

Masashige Tsuji

Koichi Yahata

Yoshio Akaishi

Hiroki Shimano

Koichi A Ono

Satoru Shigeta

Kohei Myoen

Hirokazu Matsui

Hiroaki Igarashi

Takashi Ogura

Hiroyuki Yamai

Keiji Kunii

Tetsuro Tateyama

Shinichiro Hida

In an automotive vehicle inverter control apparatus of the related art, a limp-home mode is provided, but six power sources including transformers are required for respective gate circuits of the respective IGBT drive circuits. Therefore, a reduction in size and a reduction in weight cannot be achieved, and a demand of the improvement of mountability or the improvement of fuel consumption as described above cannot be satisfied. A power semiconductor module and the drive circuit include three unit semiconductor modules and three unit drive circuits corresponding to a three-phase alternating current, and power supply units of the unit drive circuits are provided independently, whereby the limp-home mode is provided and in addition, the number of power supply units may be reduced, so that the reduction in size and the reduction in weight are achieved.

Automotive vehicle inverter control apparatus

A power converter includes an inverter, a contactor for connecting a battery to the inverter in order to supply DC power from the battery to the inverter and for disconnecting the battery from the inverter in order to stop an operation to supply the DC power from the battery to the inverter, a smoothing capacitor connected in parallel to the battery through the contactor, a discharge circuit that is provided with a discharge resistor and a switching device connected in series to the discharge resistor and is connected in parallel to the smoothing capacitor to discharge electric charge from the smoothing capacitor, a voltage measurement circuit, a voltage-dividing circuit for dividing the voltage across the terminals of the smoothing capacitor to generate a partial voltage to be input to the voltage measurement circuit and a control circuit of the switching device.

Power converter

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

According to the present invention, an overcurrent fault detection device includes: an inverter converting DC current to three-phase AC currents for driving a motor; a DC voltage detector; phase current detectors; a rotational position detector that detects a rotational angle of the motor; a control circuit that controls a gate drive circuit, which controls the inverter at every predetermined cycle, based upon the phase current values, a motor rotational angle detection value, and a speed command or a torque command from a higher-order control device; and a first decision-making circuit that detects an overcurrent based upon the phase current values at every predetermined cycle, wherein: the first decision-making circuit determines whether or not the phase current values exceed a predetermined amplitude threshold value by frequency detection for any of the phase current values exceeding the predetermined amplitude threshold value, and determines that an overcurrent has occurred upon detecting the frequency.

Overcurrent fault detection device for electrical drive control system

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

A discharge circuit for a DC power supply smoothing capacitor that is used in a power conversion device that supplies DC power via a switch to the DC power supply smoothing capacitor and an inverter, includes; a resistor that discharges charge in the capacitor; a switch connected in series with the resistor, that either passes or intercepts discharge current flowing from the capacitor to the resistor; a measurement circuit that measures a terminal voltage of the capacitor; and a control circuit that controls continuity and discontinuity of the switch; wherein the control circuit, after having made the switch continuous and starting discharge of the capacitor by the resistor, if a terminal voltage of the capacitor as measured by the measurement circuit exceeds a voltage decrease characteristic set in advance, makes the switch discontinuous and stops discharge by the resistor.

Discharge circuit for smoothing capacitor of DC power supply

A power conversion device includes: an inverter that converts a DC current supplied from a DC power source to an AC current by engaging a plurality of switching elements, which constitute an upper arm, and a plurality of switching elements, which constitute a lower arm, in switching operation; a control unit that includes a signal generation unit that generates a switching signal carrying a command for execution of the switching operation in correspondence to each of the plurality of switching elements constituting the upper arm and the plurality of switching elements constituting the lower arm, and outputs the switching signal thus generated as a control signal; and a drive unit that individually drives each of the switching elements based upon the corresponding control signals. The control unit includes a plurality of protection circuits disposed in series on a control signal line extending between the signal generation unit and the drive unit, with each of the protection circuits outputting a control signal having been input thereto when a protective operation is not executed but outputting a control signal for setting the corresponding switching element either in a cut-off state or in an electrically continuous state in place of the control signal input thereto when the protective operation is executed.

Power conversion device

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

A power conversion device includes an inverter circuit converting DC power into AC power and including switching devices constituting upper and lower arms, a control circuit controlling the switching devices, a drive circuit driving the switching devices by a signal from the control circuit, and an insulated power supply circuit supplying power to the drive circuit. The control circuit controls a power supply voltage to be outputted from the power supply circuit to the drive circuit. The drive circuit drives the switching devices and based on a carrier frequency and the power supply voltage. The power supply circuit includes a feedback output circuit through which the voltage outputted to the drive circuit is outputted to a power supply control IC. The feedback output circuit includes a dummy load circuit which controls the voltage to be outputted to the power supply control IC based on a change of the carrier frequency.

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Hitachinaka, Japan

Yasuo Noto