Nine‐switch ac/ac current source converter for microgrid application with model predictive control

Abstract

In this study, a current source nine-switch ac/ac converter for microgrid application is presented. In contrast to traditional back-to-back configuration, the number of switching devices in the proposed converter decreases from 12 to 9 with three insulated gate bipolar transistors and three diodes reduced, which achieves simpler structure and lower cost on switching devices. In addition, in comparison with its voltage source counterparts, the proposed converter inherits the advantages of sinusoidal output voltage and current waveform and no use of dc-link electrolytic capacitor. Moreover, a model predictive control (MPC) without weighting factor selection issue is designed for the proposed converter to realise both sides’ power flow regulation. Simulation and experiments have been conducted, which validate the effectiveness of the proposed converter and MPC scheme.