Sensorless Control of IPMSM Based on Current Prediction and Nonlinear Flux Model

Reducing rotor position error is very important for sensorless control of interior permanent magnet synchronous motor (IPMSM). However, classical motor models do not describe nonlinear parameter changes and cross-coupling effects, which lead to rotor position offset errors. To solve this problem, a nonlinear motor incremental inductance model is introduced in this paper. Use the designed polynomial function to fit the flux linkage and incremental inductance. In the low-speed operation region of the motor, the incremental inductance model is applied to the high-frequency voltage injection method, and the current predictive model is used to estimate the rotor position, and finally reduces the rotor position error caused by magnetic saturation and cross-coupling effects, and greatly improves the accuracy of position estimation under low-speed and heavy-load conditions. Finally, the effectiveness and feasibility of the proposed method are verified by experiments.