Three-Vector-Based Model Predictive Current Control With Zero-Sequence Current Suppression for Open-Winding LPMVM Drives

Abstract

Because of the enhanced utilization of dc-link voltage and the low cost of power supply, common dc-link dual-inverter is a desirable drive topology to solve the low power factor problem of open-winding linear permanent-magnet vernier motor (OW-LPMVM). However, the common dc-link structure causes a zero-sequence current (ZSC) in the motor windings, which increases current distortion and thrust ripple of the LPMVM. To effectively decrease the ZSC as well as thrust ripple, this paper proposes a three-vector-based model predictive current control (TV-MPCC) scheme. In the proposed TV-MPCC, one optimal vector produced by one of the dual-inverter is obtained based on the deadbeat current control principle, which simplifies the prediction process and reduce the switching frequency. On the other hand, the other two optimal vectors produced by another of the dual-inverter are obtained by means of a cost function cascade evaluation, which improves the steady-state performance. With the proposed scheme, the ZSC is effectively suppressed with the simple implementation, enhanced thrust performance, fast transient response, good robustness against parameter variations, and reduced switching frequency compared with the existing ZSC suppression methods. Simulation and experimental results are demonstrated for confirming the proposed TV-MPCC.