Model-Free Predictive Pulse Pattern Control for Permanent Magnet Synchronous Motor Drives

High-power permanent magnet synchronous motor (PMSM) drives require an efficient control strategy. Model predictive pulse pattern control (MP3C) is a promising solution in reducing total harmonic distortion (THD) when the machine operates at a high modulation index. Existing research on MP³C for PMSMs regulates phase currents indirectly by tracking the reference stator flux linkage from a machine model. However, the method would result in static current errors when the motor parameter mismatch exists. This article proposes a model-free predictive pulse pattern control (MFP³C) with current tracking capability to solve the problem. The new approach can offer the same THD level as the MP³C and eliminate the parameter dependence issue simultaneously. A comparative study on a simulated PMSM model is conducted to demonstrate the advantages of the proposed design.

I. Introduction

Permanent magnet synchronous motors (PMSMs) are promising traction machine candidates for industrial applications due to high efficiency and high power density [1]–[4]. Space-vector pulse-width modulation (SVPWM) is a common approach to drive the PMSM with a constant switching frequency. However, it has limited performance at medium and high speeds due to the reduced carrier-to-fundamental frequency ratio. Current total harmonic distortion (THD) increases at a higher speed, aggravating torque ripples and increases power losses. As an alternative, optimal pulse pattern (OPP) modulation is effective in enhancing the current quality [5]–[8].