Vehicular electric power steering device

摘要

An electric power steering device controls an electric motor (14) through a program processing based on a steering torque detected by a torque sensor (50) and a vehicle speed detected by a vehicle speed sensor, and applies a suitable assisting force to rotational motion of a steering handle. Occurrence of an abnormality in the torque sensor (50) and a power circuit (41) is detected through the program processing. The torque sensor (50) is activated upon receipt of a power-supply voltage from the power circuit (41) and detects a steering torque. If a power-supply voltage outputted from the power circuit (41) has dropped, detection of an abnormality in the torque sensor (50) is forbidden. If a power-supply voltage supplied from a battery (25) to the power circuit (41) has dropped, detection of an abnormality in the power circuit (41) is forbidden. <IMAGE>