Sensorless control for permanent magnet synchronous motors with reduced parameter sensitivity

This paper presents an enhanced back-electromotive-force based sensorless control algorithm for permanent magnet synchronous motors with reduced sensitivity to parameter deviations. The key contribution is the analytical demonstration that incorporating an integral term in the position regulator achieves steady-state insensitivity to permanent magnet flux linkage and direct-axis inductance variations. Transfer function analysis shows that whilst speed estimation remains inherently robust, position estimation can be rendered insensitive through proper observer design. Experimental validation demonstrates, that a significant flux linkage deviation can be tolerated without affecting dynamic performance. The enhanced algorithm provides robust sensorless control for automotive applications where parameter variations significantly affect performance.