The common-mode voltage suppression method for PMSM based on current predictive control

The traditional common-mode voltage (CMV) suppression method, based on current predictive control model, exhibits a significant issue with large current harmonics. This paper proposes a common-mode voltage suppression method based on model predictive control, which can reduce the common-mode voltage and current harmonics of the motor under various working conditions. Firstly, the structure of the two-level voltage source inverters (2L-VSIs) is analyzed, and the reasons for the generation of common-mode voltage are obtained. Secondly, the implementation principle of the virtual vector method is given and a non-zero vector modulation method based on current predictive control is proposed. The calculation method of the action time corresponding to each vector is also given. Then, in order to reduce the current prediction error caused by model parameter mismatch, a Romberg observer with feedforward compensation function is added to the proposed control system. The current prediction performance of the model is further improved. Finally, simulation and experimental results show that the proposed method can effectively attenuate the common-mode voltage and significantly reduce the current harmonics.