Dual-fault tolerant control method of feedback loop for permanent magnet synchronous motor

A low-price dual-fault tolerant control method of feedback loop for permanent magnet synchronous motor is proposed without extra hardware and sensors in an electromechanical actuator. In this method, position feedback of electromechanical actuator is used to accomplish the vector control of motor and speed control of actuator if the rotor position sensor falls in fault. And rotor position sensor of motor is used to complete the position and speed control of actuator if the position sensor of actuator fails. This control method is realized by a rotary actuator and DSP-based controller, which is verified by experiments. The results show that the error of static and dynamic performance is 5% lower than the normal work conditions and the change of steady current is less than 15%. Combined with the potentiometer redundancy by resolver, the position control, speed control and current control of PMSM perform with higher reliability without increasing cost.