Current controller of three-phase VSI using FCS-MPC with optimal active and zero vector selection for balanced loss distribution and switching loss reduction

High switching loss remains a predominant issue in conventional finite control set model predictive control (FCS-MPC) for voltage source inverter, aside from the uneven distributed loss between upper switches and lower switches. While maintaining the inherent simplicity and effective reference tracking capability of conventional FCS-MPC, a new FCS-MPC is proposed to acquire substantial improvement in switching loss reduction by choosing the optimal zero vector and two active vectors. Selection of the two active vectors is performed by considering two legs that have maximum and minimum output voltage at particular sampling instant, while the selection of the optimal zero vector is based on the switching states of the previous sampling instant. The proposed method also ensures uniformly distributed loss in each phase as well as between upper switches and lower switches. Further switching loss reduction by selecting the appropriate weighting factor in the cost function is investigated for both the conventional and proposed methods as well. A loss model is constructed in MATLAB/SIMULINK for analyzing quantitative switching loss, conduction loss, total harmonic distortion, and number of switching. The proposed method ensured its superior performance under different load angles and sampling periods, and all the results are verified through simulation.