Dual-Vector Predictive Current Control of Open-End Winding PMSM With Zero-Sequence Current Hysteresis Control

Abstract

Dual-inverter fed open-end winding permanent magnet synchronous motor (OW-PMSM) drive topology can extend the speed range under limited dc bus voltage, but it suffers from the zero-sequence current (ZSC) problem when with common bus configuration. Predictive current control (PCC) is a potential high-performance control method for electric drive. However, the PCC algorithm for dual-inverter system may bring a huge computational burden because of more space vectors (SVs) to traverse. In order to improve the steady-state current performance and suppress the ZSC, this article proposes a dual-vector PCC (DV-PCC) method for OW-PMSM with ZSC hysteresis control. The reference voltage vector is predicted in advance according the model. A novel sector judgment method is used to judge the sector and subsector where the reference voltage vector is located, and determines the two candidate SVs. Then the dwell time of the two candidate SVs is calculated through the projection length of the reference voltage vector. Moreover, the switching states redundancy feature of dual-inverter system is employed to suppress ZSC. As some SVs correspond to multiple switching states of different zero-sequence voltages (ZSVs), the switching state whose ZSV polarity is opposite to the ZSC polarity is selected as the output to realize the hysteresis control of ZSC. When the ZSVs of the candidate SVs contradict the hysteresis control demand, the zero-vector insertion method is used to guarantee the effective suppression of ZSC. The experiments are implemented in comparison with the existing DV-PCC method.