ELECTRIC POWER STEERING APPARATUS

摘要

Disclosed is an electric power steering apparatus which permits a driver to clearly sense a changeover in a control mode and which does not give a sense of unease to the driver. The electric power steering apparatus is provided with a motor which generates auxiliary steering force that reduces the driver's necessary steering strength, and a control device which determines control values for this motor, the aforementioned control device determining control values in such a way that different maps showing correlations between state quantities of a vehicle and control values are used separately for a plurality of control modes so as to suit the purposes of the individual control modes. When the control device changes over a control mode (a normal mode or a sports mode), a gradual transition is made from a control value based on a map corresponding to a previous control mode to a control value based on a map corresponding to a new control mode. The changeover period for gradually changing a control value at this time is set in such a way as to differ according to the control mode before and after the changeover.