Position sensorless control of synchronous reluctance motor using high frequency current injection

This paper presents a position sensorless control scheme of a synchronous reluctance motor using high-frequency current injection. The rotor has inherent rotor saliency and its angle is estimated from d and q stator current injection and the appropriate signal demodulation. This scheme gives robust and dynamic estimation of the rotor angle independent of the operating conditions including standstill, light and heavy loading. Experimental results of closed loop speed control of a 3.75 kW axially laminated synchronous reluctance motor are given to verify the proposed scheme.