Improved Sequential Model Predictive Control of Open-Winding Permanent Magnet Synchronous Motor With Pseudo 3-D Space Vector Modulation

This paper proposes a novel pseudo 3-D space vector modulation (SVM)-based sequential model predictive control (SMPC) for the open-winding permanent magnet synchronous motor (OW-PMSM), which eliminates the weighting factor and improves the current quality. In the OW-PMSM drive with a common dc bus, because of the large difference between the 0-axis and dq-axes impedance, the weighting factor is required in traditional model predictive control (MPC) to balance the 0-axis and dq-axes current control. To avoid the weighting factor and its tedious tuning work, an improved SMPC is put forward, where two sequential predictive stages are established to evaluate voltage vectors (VVs). In the first stage, several possible zero-sequence voltage components of all candidate VVs are evaluated to obtain the VV group with the best 0-axis current tracking performance. In the second stage, according to dq-axes current control, a multivector-based modulation scheme is designed to synthesize the optimal VV. Due to the characteristics of the modulation process in two predictive stages, the proposed modulation process is named pseudo 3-D SVM, which achieves better current quality and output performance. Experimental verification is provided to prove the effectiveness of the proposed scheme.