Selective Harmonic Elimination Modulation for HVDC Modular Multilevel Converter

Abstract

This paper proposes the application of a mixed selective harmonic elimination mitigation modulation algorithm to three-phase HVDC modular multilevel converters. Defining 1 the number of levels, two cases have been considered: t=65 and t=257. While operating at the fundamental switching frequency, the algorithm returns those solutions, expressed in terms of switching angles to be applied to power devices, which allow complete elimination of a subset of low order harmonics and the mitigation of others. Simulation results show harmonic analysis graphs and total harmonic distortion at different modulation indexes and demonstrate the feasibility of the proposed system.