Abstract: A motor actuator of the present invention includes, between a battery and an inverter, a first solid state relay and a second solid state relay in which directions of parasitic diodes are opposite to each other. When supply of power from the battery to the inverter is to be interrupted, the first solid state relay is brought into an OFF state or all of a plurality of field effect transistors are brought into the OFF state, and then the second solid state relay is brought into the OFF state.

Abstract: An EPS control apparatus (2) having two electrical systems connected to external power supplies (6A, 6B) includes, in each electrical system, inverters (11A, 11B) driving a motor (1), control circuits (12A, 12B) controlling the inverters, and negative connectors (14A, 14B) connecting control system negative lines (18A, 18B) from a control system common ground (23) and drive system negative lines (17A, 17B) with negative power supply lines (62A, 62B). EPS control apparatus (2) also includes connection lines (25) connecting drive system negative lines (17A, 17B) and a current state detection circuit (24) detecting current states of connection lines (25). The control circuits detect open faults in connectors or negative power supply lines in their respective systems based on the current states. If an open fault is detected, the corresponding control circuit limits control on the inverter in its system. Otherwise, the control on the inverter in the system is continued.

Abstract: A motor actuator of the present invention includes, between a battery and an inverter, a first solid state relay and a second solid state relay in which directions of parasitic diodes are opposite to each other. When supply of power from the battery to the inverter is to be interrupted, the first solid state relay is brought into an OFF state or all of a plurality of field effect transistors are brought into the OFF state, and then the second solid state relay is brought into the OFF state.

Abstract: The electronic control unit includes first and second power connectors, first and second ground connectors, first and second inverters, first and second control circuits, and first and second current-voltage conversion elements. Each current-voltage conversion element is provided between a ground of the corresponding first or second inverter and a common ground of the first and second control circuits, and measures a ground current of the corresponding first or second control circuit. Then, each control circuit determines that the corresponding first or second ground connector is in an abnormal state based on a current flowing through the corresponding first or second current-voltage conversion element.

Abstract: The electronic control unit includes first and second power connectors, first and second ground connectors, first and second inverters, first and second control circuits, and first and second current-voltage conversion elements. Each current-voltage conversion element is provided between a ground of the corresponding first or second inverter and a common ground of the first and second control circuits, and measures a ground current of the corresponding first or second control circuit. Then, each control circuit determines that the corresponding first or second ground connector is in an abnormal state based on a current flowing through the corresponding first or second current-voltage conversion element.

Abstract: A motor driving device controls driving of an inverter device, detects current values in two phases, and compensates a value. The motor driving device detects current values in two phases, namely, a maximum phase current value and a minimum phase current value, within a single cycle of a PWM carrier frequency. The motor driving device compensates a value obtained by subtracting an absolute value of a difference between two absolute values, namely, the detected maximum phase current value and minimum phase current value, from the smaller value of the absolute values, as the offset current component.

Abstract: A motor drive device includes an inverter that drives a motor, a power source smoothing capacitor of the inverter, and a control unit that controls the inverter to drive the motor. The control unit precharges the capacitor with a power source voltage, and calculates a capacity value of the capacitor, based on a ratio of the power source voltage and a voltage with which the capacitor is charged, or an amount of time taken until the voltage with which the capacitor is charged, after the passage of a predetermined amount of time from the start of the precharge, reaches a voltage corresponding to the power source voltage. The control unit performs torque limitation of the motor when the capacity value of the capacitor has decreased.

Abstract: An object of the present invention is to provide an inverter driving device and an electric system which are capable of accurately detecting an offset amount of a current detection circuit that detects a motor current using a direct bus current, and compensating for the detected offset amount, to improve detection accuracy of the motor current and control the motor appropriately, without increasing the number of components of the inverter driving device.

Abstract: A motor drive device includes an inverter that drives a motor, a power source smoothing capacitor of the inverter, and a control unit that controls the inverter to drive the motor. The control unit precharges the capacitor with a power source voltage, and calculates a capacity value of the capacitor, based on a ratio of the power source voltage and a voltage with which the capacitor is charged, or an amount of time taken until the voltage with which the capacitor is charged, after the passage of a predetermined amount of time from the start of the precharge, reaches a voltage corresponding to the power source voltage. The control unit performs torque limitation of the motor when the capacity value of the capacitor has decreased.

Abstract: In related art technique, an average neutral point voltage is detected via a low-pass filter. Time constant of the low-pass filter must be set to cover the entire output frequency band of an inverter and voltage fluctuation due to modulated signal must be separated from that due to a short circuit to ground. According to the present invention, whether abnormality such as a short circuit to ground or to supply occurs in output lines can be determined based on an actual neutral point voltage of a motor, which changes in a stepwise fashion in conformity to a PWM pulse pattern output by an inverter device, and a normal neutral point voltage which depends on a PWM pattern output by the inverter device. Highly reliable abnormality detection in accordance with the waveform of the neutral point voltage and stable abnormality detection not depending on the inverter output frequency are feasible.