An FCS-MPC-based Closed Loop Control for Matrix Converter Under Unbalanced Grids

A finite control set-model predictive control (FCS-MPC) based closed loop control method is proposed for the matrix converter (MC) under unbalanced grids in this paper. The proposed method involves the outer loop PR control and the inner loop FCS-MPC. The outer loop PR controller is used to control the source currents and generate the input current reference for FCS-MPC. In the proposed FCS-MPC, the input currents and the output currents of MC are controlled. The sinusoidal source current reference for PR controller is solved by the novel definition of instantaneous power, so the phase lock loop (PLL) and complex positive-/negative- sequence decomposition of grid voltages are not required. Compared with the conventional FCS-MPC for MC, the proposed method has less computational burden because the 27 calculations of source current and input voltage predictions are avoided. Finally, the correctness and feasibility of the proposed method are verified by the simulations.