Evaluation of a simplified high frequency injection position sensorless control method for reluctance synchronous machine drives

In this paper a simplified and stable high frequency injection sensorless control method for reluctance synchronous machine drives is presented. This method is based on previous work where the conventional band pass filter is omitted from the demodulation scheme to prevent unnecessary time delay and magnitude decrease. Previous work presented accurate position estimation at very low speed under no-load conditions. The proposed method is evaluated under various different load conditions and at high speeds. The performance of the proposed method is compared to the performance of the drive while using a rotary encoder. Experimental results show that the scheme is stable under various load conditions and delivers good performance.