Optimal configuration of modular redundancy for MMC

Abstract

A method of optimal configuration for modular redundancy of MMC(Modular Multilevel Converter) is proposed, which establishes a multi-objective optimization function and obtains the optimal quantity of redundant sub-module to increase its utilization rate and enhance system reliability. The topological structure of MMC and the operation mechanism of its sub-module are analyzed. The protection schemes of study of module redundancy are studied and the specific steps of its optimal configuration are given, which are analyzed for engineering application. Simulative results show that, the optimal redundant sub-module configuration is simply and effectively obtained, which ensures the reliable system operation while reduces the costs, verifying the validity and feasibility of the proposed method.