Patent ID: 7984786

Claim:
An electric power steering device, comprising: an electric actuator which is supplied with power from a power supply device to generate a predetermined steering assistance force for a steered wheel; an actuator controller which controls the amount of electrical power supplied to the electric actuator, according to the steering state of a steering wheel; and a power supply voltage detector which detects the power supply voltage of the power supply device, wherein the actuator controller comprises a voltage maintenance controller which controls the electrical current supplied to the electric actuator, so as to maintain the power supply voltage greater than or equal to a set voltage which is set in advance, wherein the voltage maintenance controller adjusts the electrical current amount supplied to the electric actuator based upon the deviation between the detected power supply voltage and the set voltage, and performs feedback control based upon the deviation between the detected power supply voltage and the set voltage so that the power supply voltage becomes equal to the set voltage.