MOTOR DRIVE DEVICE, MOTOR DRIVE DEVICE DIAGNOSIS METHOD, AND ELECTRIC POWER STEERING APPARATUS USING MOTOR DRIVE DEVICE

摘要

Provided is a motor drive device capable of suppressing current consumption and increase of cost without delaying the start-up time. The motor drive device is provided with multiple inverter circuits, multiple relay circuits, multiple power-supply-stabilizing capacitors, multiple precharge circuits, and a control unit. The inverter circuits drive a motor including multiple winding sets by separately using the winding sets. The relay circuits are provided between a power supply and the respective inverter circuits. The capacitors are provided between the respective relay circuits and the respective inverter circuits. The precharge circuits are provided so as to correspond to the capacitors, and charge the respective capacitors before the relay circuits are driven. The control unit is configured to control the precharge circuits at the time of diagnosis of the relay circuits such that: the precharge circuits charge the respective capacitors while causing the timings, at which the precharge circuits charge the respective capacitors, not to coincide with each other; or the precharge circuits charge the respective capacitors alternately.