The improvement of model predictive control based on three-level three-phase inverter

摘要

Toimprovethedynamicresponseoftheinverter,theconventionalproportional–integralcontroller and the modulation part are substituted by the finite-control step model predictive control (FCS- MPC)strategy.Comparedtothetwo-levelinverter,thedriftedneutralpointpotentialisanissuethat cannot be neglected. To resolve this issue, the cost function is modified in this paper. Besides, as all of the voltage vectors are employed during optimal research progress in FCS-MPC, the switch- ing frequency is variable, which burdens the filter. The complex calculation progress also burdens the microcontroller. According to the conventional modulation algorithm, the voltage vectors are divided into several groups and the optimal calculations are simplified with them. Based on that modification, the switching frequency is fixed. Finally, the simulation and the experimental results are demonstrated, which reveal the validity and merits of the proposed method.