Novel sensorless phase modulation drive for a field assisted switched reluctance motor

This paper presents a novel method to estimate the rotor position of a new field assisted switched reluctance motor at standstill and also low speeds. In this method, a high frequency sine wave signal is applied to the field assisted winding on the stator and then the phase of induced signals on each phase winding is monitored to detect the rotor position at standstill. It then continues to sense the rotor position while the motor is running at low speed by utilizing the same sine wave signal to the field winding. In the running mode, the phase of induced voltage on each un-energized stator winding is measured and compared to other phases. The prototype of the motor and its drive were made and investigated experimentally results. The experimental results demonstrate the feasibility and practicability of the method.