A Novel Sensorless Loss Minimization Control Method for High-speed SPMSM

In this paper, on the basis of sensorless control, the efficiency optimization of high-speed surface-mounted permanent magnet synchronous motor (SPMSM) is studied. The loss minimization control (LMC) method can optimize the air gap flux with the regulated d-axis current, thereby improving the efficiency of PMSM. However, it requires accurate rotor position and speed. For high-speed SPMSM, its speed and position accuracy obtained by general sliding mode observer (SMO) and arctangent operation are limited. For sake of improving the estimated position and speed accuracy of estimated speed and position, this paper uses two improved fundamental frequency extractors to process the observed back-electromotive force (EMF). And the accurate rotor position and speed is extracted by an orthogonal phase-locked loop (PLL). Then, for high-speed SPMSM, on the basis of the accurate position and speed, its efficiency is optimized by LMC strategy. Finally, the proposed method is proved to be valid by simulation.