A new simplified sensorless control method for a single phase SR motor using HF signal injection

This paper presents a new simplified sensorless control method for a single phase switched reluctance motor (SRM) that has a unique stator design. The rotation of the rotor is partly achieved by energizing the single phase stator winding and partly by a permanent magnet embedded in the stator. A different sensor-less control method is investigated. The method is based on high frequency signal injection, which injects a signal into two isolated sensing coils on the stator. This method minimizes or eliminates the effect of the emfs induced from the main motor winding onto the injected signal by common mode rejection. This significantly improves the signal to noise ratio of the injected signal and simplifies the processing of the signal in order to obtain rotor position information. The method is evaluated experimentally and the results are presented.