A novel sensorless method for rotor position detection in bifilar SRM drive

This paper presents a new sensorless method for controlling a Three-Phase Switched Reluctance Motor utilizing bifilar drive. In this method rotor position is extracted by analyzing the current results of injected high frequency diagnostic pulses to the motor windings. The proposed method is based on the dependency of the phase current slope that achieved from the diagnostic pulses to the rotor position. The new method is applicable at standstill as well as the running mode. The use of bifilar windings for rotor position detection makes the control circuit to be completely isolated from main winding and the power transistors. Also the simplicity of hardware and control algorithm minimizes the cost of drive. The proposed method was implemented on a 3-phase 6/4 SRM with bifilar windings and the experimental results demonstrated the accuracy and function ability of this method.