To provide a control device of a power steering device capable of effectively enhancing the detection accuracy of the number of rotation of an electric motor.
An electric power steering device comprises an electric motor 3 which is driven by the power supplied from a power source 2 to assist the steering force by a driver, an electric motor unit 15 having a switching element 8 which is interposed between the electric motor 3 and the power source 2 to switch the power supply state from the power source 2 to the electric motor 3, a target voltage calculation means 14 to calculate the target voltage according to the target torque of the electric motor 3, a switch operation control means 7 to switch-control the switching element 8 based on the target voltage calculated by the target voltage calculation means 14, and a resistance operation means 9 to obtain the resistance of the electric motor unit 15 based on the target voltage calculated by the target voltage calculation means 14.
OTA TAKASHI
MOTOYAMA YASUO
