An inductance profile demodulator based observer for sensorless control of switched reluctance motors

Abstract

An alternative strategy to control the SRM without a position sensor is proposed. Sensing currents are injected into idle SRM phases. The sensing currents are then demodulated to generate an error function that is input to a state observer. This inductance profile demodulator based observer estimates rotor position and speed continuously and is capable of operation down to zero speed. The demodulator based observer's performance is analyzed and verified using simulation and experiments.