Observation Method for PMSM Rotor Position Based on High Frequency Signal Injection

A simple but effective method to observe PMSM rotor position is presented in this paper. A high frequency voltage is injected into the motor and it will cause a little change of current signal because of the anisotropy of the machine. By processing the current in the armature, this method can calculate the rotor position accurately. This paper also presents a new way to observe the original rotor position when PMSM is standstill. The results of simulation show that this method can work feasibly and effectively.