DRIVE SYSTEM AND CONTROL METHOD OF THE SAME

摘要

In response to a system-off instruction, the drive system control technique of the invention controls individual motors of an electric cooling water pump and an electric cooling fan to stop (step S100), waits for elapse of a preset reference time period since start of the control of stopping the motors (step S110), and turns off a relay to disconnect a supply of electric power from a battery to a CPU of a control unit (step S120). Inactivation of the relay after elapse of the preset reference time period since start of the control of stopping the motor disconnects the supply of electric power to the control unit in the state of sufficiently low back emf generated by the motors. This arrangement effectively prevents malfunction of the control unit due to the back emf generated by the motors.