Position sensorless control for switched-reluctance motor drive with adaptive commutation tuning

This paper presents the position sensorless control for switched reluctance motor (SRM) drive having improved performance via adaptive self commutation instant tuning (ACT). The narrow voltage pulses with suited frequency and duration are injected into an un-energized phase winding via the PWM channel. The resulted amplitude modulated winding currents are sensed and signal processed to yield the observed Hall signal for sensorless control. The determination of key parameters of the proposed sensorless control scheme and the effects of resulted amplitude modulated winding currents are analyzed. No external injection circuit and the motor parameters are required. The observed speed is obtained from the sensed four winding currents. The motor is first started in stepping motor mode, and then it is changed to the sensorless SRM mode as the speed is raised to a suited value. To improve the torque generating capability, an adaptive self commutation control scheme with the identified winding inductance is developed. Experimental evaluation shows that the developed position sensorless SRM drive possesses good driving performance within a reasonably wide speed range.