Modular Multilevel Converter for Unified Power Flow Controller Application

This paper presents a novel unified power-flow controller (UPFC) topology based on modular multilevel converter (MMC). A reduced switching-frequency phase-shifted pulse-width modulation scheme including voltage balancing strategy is described for the operation of the proposed MMC-based UPFC. In order to suppressing second harmonic component in arm current , this paper further discusses circulating current suppressing method. At the end of this paper, dynamic performance of the proposed MMC-based UPFC is evaluated in Matlab/Simulink environment. The reported time-domain simulation results show the validation of control strategy.