High performance position sensorless control using rotating voltage signal injection in IPMSM

This paper describes a new position sensorless control method based on the high frequency rotating voltage signal injection to an Interior Permanent Magnet Synchronous Motor (IPMSM) drives. In this method, the rotor position can be directly calculated from four successive sampled current and voltage values. Compared to conventional heterodyning process, the proposed method is simple to implement and appropriate to increase the frequency of the injection signal up to a half PWM switching frequency. Because of the higher frequency injection and no low-pass-filter in demodulation, the control performance can be enhanced conspicuously.