Adaptive Capacitor Voltage-Based Model Predictive Control for Open-Winding PMSM System With a Floating Capacitor
Weihuang Ke, Dan Sun, Xu Zhang, Heng Nian, Bin Hu
Abstract
In this article, an adaptive capacitor voltage-based model predictive control (ACV-MPC) strategy for the open-winding permanent magnet synchronous motor system with a floating capacitor (FC-OW-PMSM) is proposed. The control precision of the conventional model predictive control (CMPC) strategy is improved by adjusting the capacitor voltage without using high switching frequency methods. The position of voltage vectors (VVs) is uncertain under different capacitor voltages. To establish a unified motion process of the uncertain VVs, the VV trajectories are analyzed. Furthermore, a novel region division scheme is proposed to locate the candidate VV trajectory. To further determine the reference capacitor voltage and select the candidate VVs from the candidate VV trajectory, the proposed scheme is analyzed in each VV trajectory. Finally, a cost function with only one capacitor voltage constraint is carried out to select the optimal VV, and thus, the weighting factors and the complicated iterative process are both avoided. Experimental studies are carried out to verify the effectiveness of the proposed strategy.