Patent ID: 8878474

Claim:
A motor control device for supplying from a power supply and controlling a current to flow through a motor provided with a plurality of sets of windings, comprising: a plurality of inverters comprising a switching element in each of phases of the plurality of sets of windings for controlling a voltage applied to the each of the phases, thereby controlling a current to be supplied from the power supply to the each of the phases of the plurality of sets of windings; a power supply relay provided between the power supply and the plurality of inverters for disconnecting an electrical connection; and current control means for providing, depending on a target value of a torque to be generated by the motor, each of the plurality of inverters with a voltage command corresponding to the voltage, thereby controlling the current to flow through the plurality of sets of windings, wherein: the current control means comprises: primary failure detection means for detecting the primary failure of any one of the plurality of sets of windings and the plurality of inverters; and secondary failure detection means for detecting, after a primary failure is detected, a secondary failure occurring in any one of a winding and an inverter in a system in which the primary failure has occurred; and the current control means is configured to: when the primary failure detection means detects, in any one of the plurality of inverters and a part of the plurality of sets of windings, any one of a short-circuit failure, a ground-fault failure, and a power-supply-fault failure as the primary failure, continue control for an inverter on a normal side; and further, when the secondary failure detection means detects the secondary failure, open the power supply relay.