Patent ID: 8981691
Filing Date: 2015-03-17
Classification: H02P

Abstract:
1. A motor drive apparatus for driving a motor including a plurality of coil sets, each of which is formed of coils of a plurality of phases, the motor drive apparatus comprising: a plurality of inverter circuits, which is provided in correspondence to the plurality of coil sets and supplies electric power to the plurality of coil sets by converting an electric power supplied from an electric power source; an electric power supply on/off control circuit, which is provided in each power supply system between the electric power source and the inverter circuit and electrically conducts and interrupts the electric power source to and from the inverter circuit; a failure detection part, which detects a failure in the inverter circuit in each power supply system; a drive control part, which stops the inverter circuit in a failing power supply system from driving the motor, the failing power supply system corresponding to the power supply system having the failure detected by the failure detection part; and an on/off control part, which controls the electric power supply on/off circuit of the failing power supply system to a regenerative current conduction state when the failure detection part detects the failure, the regenerative current conduction state allowing the regenerative current to flow in a direction from the inverter circuit to the electric power source, wherein: the electric power supply on/off circuit includes a series connection of at least one first on/off switch and at least one second on/off switch; the first on/off switch is a semiconductor switching element having a parasitic diode, which allows a current to flow only in a direction from the inverter circuit to the electric power source; the second on/off switch is a semiconductor switching element having a parasitic diode, which allows only a current to flow only in a direction from the electric power source to the inverter circuit, and wherein the on/off control part is capable of controlling the first on/off switch and the second on/off switch independently; and the on/off control part turns off the first on/off switch and turns on the second on/off switch in the failing power supply system, when the failure detection part detects the failure.