NONLINEAR CONTROL OF THREE-PHASE THREE-LEVEL AC/DC CONVERTER

Abstract

This paper presents a nonlinear control technique for a three-phase three-level AC/DC converter based on the combination of feedback linearization control theory and sliding mode control. First, a non-linear model was applied in a rotating reference frame (dq). Then, the controllers for DC-link capacitor voltage and mains current are designed, based on nonlinear control theory. Based on the proposed control technique, the three-phase three-level AC/DC converter gives better performance, compared to the classical PI controller. Simulation for three-phase three-level AC/DC converter using PSIM was performed to verify the proposed controller.