Sensorless Rotor Position Detection for SRMs with Drive Current-isolated Signaling System

Abstract

The switched reluctance motor(SRM) is considered a good candidate for a power source in harsh environments owing to its simple structure. However, it needs a rotor position sensor, which is generally unsuitable for those kinds of applications. In this paper, a novel method for detecting the rotor position without those sensors by introducing common mode signaling in the windings is presented. The signal is injected and detected in such a way that it is isolated from the current commutated for torque generation. The simulation results of the scheme will be shown to be practical. An experimental setup based on the signaling method successfully drove an SRM at rotational speeds over 100,000min^-1. Through the simulation and the experiment, the scheme has been proved to be practical and suitable for high rotational rate applications.