Cascade Finite Control Set Predictive Control of Neutral Point Clamped Power Converter

In this paper, a finite control set predictive control in cascade with PI controller is presented for a three-phase neural point clamped boost rectifier. The control algorithm consists of a finite control set predictive control for inner current loop in synchronous reference frame and a PI voltage control for the outer-loop system. There are two reference signals for this cascade controller, one being the de link voltage reference and the other q-axis current reference, which are used to regulate the de link voltage and achieve an unity power factor. A physical model is used for the design of finite control set predictive controller in the inner-loop and an empirical model is used for the design of PI controller for the outer-loop. Simulation results show the satisfactory closed-loop control performance for the de-link and the q-axis current regulation.