Model predictive control for a 27-level asymmetric multilevel STATic COMpensator

Recent publications on multilevel converters show different topologies and control to obtain an improvement in the sinusoidal AC waveforms, controlling simultaneously the DC voltage and the active/reactive power. This paper presents a 27-level asymmetric multilevel converter used as a STATic COMpensator, aimed to inject/absorb the reactive power consumed/produced by an inductive/capacitive load. The control strategy includes a master-slave approach that considers a predictive controller for the current tracking in the inner loop and a PI linear control to keep the DC voltages in their reference values for the outer loop. The use of the park transformation and its inverse are required to generate the references for the predictive algorithm. Dynamic tests obtained through simulations are included to demonstrate the feasibility of the approach.