Low Common-Mode Voltage FCS-MPC Algorithm for 3L-NPC Inverters Based on LaGrange Extreme Conditions

For the 3L-NPC-type inverter, finite set model predictive control algorithm exists for multi-objective control, which suffers from the difficulty of parameter tuning and affects the output current harmonics. Low common-mode voltage FCSMPC algorithm for 3L-NPC inverters based on LaGrange extreme conditions is proposed. This strategy suppresses the common-mode voltage by screening vectors, constructing alternative vectors to suppress the neutral point voltage fluctuations. Multiple vectors are utilized to reduce the current ripple and THD. The final experimental results verify that the algorithm has good results in output waveform quality, NPV fluctuation, and CMV stability.