Indirect position estimation method for switched reluctance motor using searching windings

This paper presents a new method to estimate rotor position indirectly for 12/8 switched reluctance motor (SRM). In this method, searching windings and main windings are wound on stator together. The structure of searching windings is designed to reduce induced voltages caused by main windings. High frequency voltage is applied to searching windings and the position signal is derived from induced high frequency signals. High frequency voltage can be injected from standstill to high speed in this method, thus it can operate in a wide speed range. The proposed method is implemented on a 12/8 SRM and the experimental results demonstrate the validity of this method.