A Simplified Novel Sensorless Control of SRM

This paper describes a simplified novel method of sensorless detecting excitation position for switched reluctance motor (SRM) drive. The proposed sensorless excitation position is based on the amplified detecting phase current by the short dc pulse voltage according to the rotor position during detecting period. In the proposed sensorless scheme, a phase winding has excitation, detecting and non-excitation period respectively. The turn-on and turn-off positions of SRM are determined by the detecting period of the previous excited and next exciting windings with detecting phase current levels that are inverse-proportional to rotor position. During the detecting period of a phase, the different phases turn-on and turn-off position are determined by the envelope of detected current level. After then detecting period is ended. In order to get the linear relationship of rotor position and detected phase current, a short test voltage is applied during detecting period. Since the proposed sensorless scheme does not use the complex inductance calculation and any look-up table of flux and position, the excitation pattern for SRM can be easily determined