A new sensorless control strategy by high-frequency pulsating signal injection into stationary reference frame

In this paper, a new sensorless control strategy by injecting a high frequency pulsating signal into the stationary reference frame is proposed. Differing from the two most popular conventional high frequency injection methods, i.e. pulsating voltage into estimated rotor synchronous rotating reference frame and rotating voltage into stator stationary reference frame, the new proposed strategy injects a pulsating high frequency carrier voltage into stator stationary reference frame. Then, the rotor position information can be retrieved from the rotor position dependent response current. The algorithm of the proposed strategy, compensation of cross-saturation effect and magnetic polarity detection are discussed and analyzed in this paper. The new proposed strategy has the advantage of fixed and simpler voltage signal injection, also the simpler and quicker demodulation from the response current comparing with the conventional high frequency injection methods. Furthermore, the experimental results based on an interior permanent magnet synchronous machine (IPMSM) demonstrate that the new proposed strategy has robust magnetic polarity detection, and can achieve accurate rotor position estimation with outstanding steady and dynamic performances.