Finite control set model predictive control of nine-switch AC/DC/AC converter

The nine-switch converter topology with 2 three-phase ac terminals has recently been utilized in the literature for ac to ac power conversion. Nonetheless, the existing control techniques essentially involve complicated linear controller design with special modulation schemes. This paper presents a simple yet high performance controller based on finite control set model predictive control (FCS-MPC) for ac/dc/ac power conversion using nine-switch topology. FCS-MPC algorithm is designed to control two ac terminals independently by making use of 27 combinations of voltage vectors. The first ac terminal which features an active front end rectifier with unity power factor is connected to power grid, while the second ac terminal is used to control three-phase load. Achievement of multiple control objectives within the same converter topology is made feasible by the use of cost function in FCS-MPC algorithm. Simulation results are presented to verify the functionality of the system.