Model Predictive Control of Master-Slave Inverters Operating with Fixed Switching Frequency

This paper proposes a Fixed Switching Frequency Model Predictive Control (FSF - MPC) for Master-Slave parallel inverters in a microgrid. The Master is a grid-forming inverter with an LC output filter, and the Slave is a grid-following inverter with an output LCL filter. The microgrid is also composed of linear and non-linear loads, as well as grid and line impedances. First, the proposed FSF - MPC is presented in details and then, in order to validate the theoretical analysis, Hardware-in-the-Loop (HIL) results are presented for different operational conditions of the microgrid, including grid connection, islanded mode and load variations. The results demonstrate the good performance of the proposed FSF-MPC, such as fast dynamic response, multi-variable control and robustness to parametric uncertainties, while also achieving fixed switching frequency.