Patent ID: 8089241

Claim:
A motor drive control apparatus configured to drive and control a motor with a supply of electric power from a direct-current power source, the motor drive control apparatus comprising: a motor drive circuit configured to selectively apply one voltage between a PWM voltage and a rectangular-wave voltage and drive the motor with the selected voltage; a voltage regulator designed to have a reactor and a capacitor and configured to regulate a voltage on a side of the motor drive circuit relative to a voltage on a side of the direct-current power source; a voltage controller configured to control the voltage regulator to make the voltage on the side of the motor drive circuit approach to a target voltage corresponding to a target operation point of the motor, the voltage controller controlling the voltage regulator to make the voltage on the side of the motor drive circuit approach to a preset target voltage that is higher than the voltage on the side of the direct-current power source when the target operation point of the motor is included in a resonance range specified by operation points of the motor in the occurrence of resonance in the voltage regulator; and a drive circuit controller configured to select a control mode of the motor drive circuit between PWM control with the PWM voltage and rectangular-wave control with the rectangular-wave voltage in a state of non-regulating the voltage on the side of the motor drive circuit relative to the voltage on the side of the direct-current power source by the voltage regulator and in a state of regulating the voltage on the side of the motor drive circuit relative to the voltage on the side of the direct-current power source by the voltage regulator and to control the motor drive circuit by the selected control mode to ensure output of a target torque from the motor corresponding to the target operation point of the motor, the drive circuit controller selecting the PWM control for the control mode of the motor drive circuit and controlling the motor drive circuit by the PWM control when the target operation point of the motor is included in the resonance range.