Sensorless control of permanent magnet synchronous machines with multiple saliencies

This work aims to solve the sensorless control problems of PMSM with multiple saliencies e. g., concentrated winding PMSM (cwSPMSM). The main contributions are as follows. The multiple-saliency model of the cwSPMSM is built based on experimental results. The physical reason for causing the secondary saliency signal is explained as well. Three saliency tracking based sensorless control methods i. e., Multi-Signal Injection method, Secondary Saliency Tracking method and Repetitive Control method are proposed for sensorless control of cwSPMSM in the low speed range and at standstill. As a necessary supplement to the saliency tracking based sensorless method, three fundamental model based sensorless control methods, Model Reference Adaptive System, Sliding Mode Observer and Extended Kalman Filter, are comparatively studied for higher speed operation. Any one of them can be combined with one of the saliency tracking based methods to formulate a hybrid scheme. The multiparameter identification is discussed to demonstrate how to improve the system robustness. Three improvements for the existing test bench, SVPWM design, Resolver demodulation design and C/VHDL code generation, are developed to further enhance the performance of the controller.