Electric power steering apparatus

摘要

An electric power steering apparatus includes a control unit for controlling a steering assist from an electric motor in accordance with steering torque detected by a torque detector. The control unit includes a plurality of assist mode generators to which are allocated respective target motor current signals representative of different steering characteristics, and any one of the assist mode generators can be switchably selected by a mode switching unit according to a predetermined condition. The mode switching unit switches between the assist modes in such a manner that one target motor current signal having been used before an assist-mode-change instruction is gradually shifted over time to another target motor current signal to be used after the assist-mode-change instruction. Thus, it is possible to prevent an unwanted abrupt change in the steering characteristic at the time of the assist mode change.