Model Prediction Control with Common Mode Voltage Suppression for Dual Three-Phase PMSM

Abstract

The system composed of dual three-phase permanent magnet synchronous motor and PWM inverter has high common mode voltage (CMV). Aiming at these problems, this article analyzed the common mode voltage characteristics of the six-phase voltage space vector and proposed a model predictive current control method (SCMV-MPCC) to suppress common mode voltage. The virtual voltage vectors (V3s) that suppress common-mode voltage were structured by linearly combining the four adjacent large vectors from 64 basic vectors, which become zero vectors in the \(z_{1} z_{2}\) planes to suppress the harmonic current. Therefore, the CMV term and \(z_{1} z_{2}\) plane harmonic current term in the cost function can be ignored. This method avoided the adjustment of multiple weight factors and optimized the prediction model. In the MPCC method, by synthesizing the low common mode voltage zero vector and introducing the duty cycle control, the optimal configuration of the action time of the virtual vector and the synthetic zero vector is realized, to reduce the stator current ripple. This method can limit the CMV to \(\pm V_{{{\text{dc}}}} /6\) and the peak-to-peak value of CMV is one third of converter DC-bus voltage under such condition as the harmonic current of stator winding is effectively restrained. Simulation results show that the proposed SCMV-MPCC method is correct and effective.KeywordsDual three-phaseSuppression of common-mode voltage (CMV)Virtual voltage vectorsModel predictive controlDuty cycle