Adaptive controller with an improved high‐frequency injection technique for sensorless synchronous reluctance drive systems.

This paper proposes an adaptive controller with an improved high‐frequency injection method for sensorless synchronous reluctance drive systems. A mathematical model is presented to show that the use of a high‐frequency injection method that takes into account the effects of unequal mutual‐inductances and the influence of speed reduces the rotor position estimation error. The adaptive speed control algorithm offers improved transient performance in comparison to typical proportional–integral (PI) controllers that are employed in sensorless drive systems. To demonstrate the viability, the proposed adaptive controller and the modified high‐frequency injection method are implemented using a TMS‐320F‐28335A digital signal processor to control a 500 W prototype synchronous reluctance motor drive. Experimental results are presented to show that the transient, load disturbance, and tracking responses of the proposed drive system are superior in comparison to a drive that uses a PI controller. Both experimental and theoretical analyses clearly indicate that the proposed high‐frequency injection method with an adaptive speed‐loop controller offers improved performance in adjustable speed synchronous reluctance drive systems. [ABSTRACT FROM AUTHOR]