A Novel Model Predictive Control via Optimized Vector Selection Method for Common-Mode Voltage Reduction of Three-Phase Inverters

In this paper, a novel model predictive control (MPC) via a double vector optimized selection method is proposed. The main idea of this method is for decreasing the high common-mode voltage of two-level inverter under balance situation, improve the tracking performance of the output current and decrease the high output current harmonic distortion rate. To solve the problem of increasing the value of total harmonic distortion (THD) due to the reduction of the available voltage vector, this method controls two voltage vectors in each sampling period for getting a better tracking performance of the output current. Simultaneously, compared with the adding virtual vector MPC method, which results in excessive switching losses, the proposed method defining the selection range of the second voltage vector. Only two voltage vectors adjacent to the first voltage vector can be selected so that the switching frequency can be greatly reduced. An experimental control platform based on Simulink-Real-Time system is presented for the further verification of the effectiveness of the proposed control method. The simulation and experimental results showed that the proposed method could effectively reduce the output common-mode voltage of the inverter. Simultaneously, the THD value and the switching loss are greatly reduced.