Low-Complexity Virtual-Vector-Based FCS-MPC With Unaffected Neutral-Point Voltage for Three-Phase T-Type Inverters

Abstract

This article presents a new finite control set model predictive control (FCS-MPC) algorithm for three-phase (3P) T-type voltage source inverters. The proposed algorithm incorporates a vector combination technique to generate a total of 51 virtual vectors (VVs), which is 89% more than the traditional algorithm, leading to excellent inverter output voltage tracking capability with reduced harmonics. Such VVs do not affect the neutral point (NP) voltage. Therefore, the NP voltage balance term can be eliminated in the cost function. In addition, to achieve a low computational burden, a three-stage optimization is employed. Experimental results validate the effectiveness of the proposed algorithm and demonstrate its superiority over conventional approaches.