A Simplified Model Predictive Control with Optimal Switching Sequence for Three-Phase Three-Level T-Type Inverter-Fed Induction Machine Drives
摘要
The conventional finite-control-set model predictive current control scheme for three-phase, three-level T-type inverter-fed induction motor drive systems is hindered by variable switching frequency, fastidious weighting factor modification, and significant computational burden. To overcome these drawbacks, this study introduces a simplified model predictive current control strategy with optimal switching sequence. Specifically, by mimicking the space vector modulation technique, a fixed switching frequency is realized by selecting a symmetrical switching sequence in order to achieve high-quality stator current performance with low total harmonic distortion. Moreover, by considering the boundary conditions and the impact of small redundant voltage vectors, duty ratios of only three voltage vectors are computed at each control cycle instead of evaluating all twenty-seven candidates, thereby reducing the computational burden and eliminating the need for a weighting coefficient. The effectiveness and robustness of the proposed methodology are demonstrated through MATLAB/Simulink simulations and hardware-in-the-loop experiments.