An Improved Model Predictive Controller for Five-Level Active-Neutral-Point-Clamped Converter

Abstract

In this paper, an improved finite-control-set model predictive controller (FCS-MPC) is proposed for five level active-neutral-point-clamped (5L-ANPC) converter. The dc-link capacitors and flying capacitor (FC) voltages, and the output current are controlled simultaneously in one control loop by employing the proposed improved FCS-MPC. In addition, the neutral point current is remarkably reduced by utilizing the proposed controller. Moreover, the cost function of the proposed improved FCS-MPC only consists of the neutral point and FC voltages, and the output current. Three decoupled pseudo functions are defined to predict the dc-capacitors and FC voltages by using only the output current. Hence, the proposed control method does not need to measure the dc-link and FC currents to predict the dc-link capacitors and FC voltages. The performance and feasibility of the proposed improved FCS-MPC for 5L-ANPC converter are verified by the simulation results.