Electric power steering apparatus

An electric power steering apparatus including a torque sensor to detect a steering torque and a motor control unit to control a motor that applies an assist torque to a steering system of a vehicle, comprising:

• a function to switch a control system of said motor between a torque control system of a torque system to control a motor output torque and a position and speed control system of a steering angle system to control a steering angle of a steering in accordance with an ON/OFF of a post-diagnosis automatic steering command being a judgment result of an automatic steering execution judging section;
• and
• a characteristic calculating section to calculate a fade gain signal F1 that applies a first fade characteristic of said torque system, a fade gain signal F2 that applies a second fade characteristic of said steering angle system, and a fade gain signal F3 that applies a third fade characteristic of said steering angle speed, sensitive to said steering torque,
• wherein, by using said characteristic calculating section when said post-diagnosis automatic steering command is switched-OFF, a post-gradual change steering-angle command value of said position and speed control is gradually changed from a steering angle command value to an actual steering angle being a column input-side absolute value or a column output-side absolute value with said fade gain signal F2, a level of said assist torque is gradually changed from 0% to 100% with said fade gain signal F1, said steering angle speed is gradually changed from 100% to 0% with said fade gain signal F3, and then said position and speed control system is operated.