Electric power steering device

摘要

The present invention provides an electric power steering device. The ECU of the device includes a microcomputer; a PWM signal generating circuit for s generating a PWM signal according to the command value; a motor drive circuit for impressing a voltage corresponding to the PWM signal upon the motor; an electric current detector for detecting an electric current flowing in the motor; an off-set limit value storage circuit for storing the restricting value showing the allowable range of the middle point voltage; a middle point oft-set voltage generation circuit for generating a voltage signal of the predetermined restricting voltage in the range of the restricting value when the actually measured middle point voltage stored in the microcomputer as the middle point voltage is compared with the restricting value; and an amplifier for outputting a signal amplified a difference voltage between the signal sent from the torque sensor and the middle point off-set voltage generation circuit.