Configuration Method for Redundant Sub-modules of Modular Multi-level Converter

Background: In this paper, we propose a redundancy configuration method for Modular Multi-level Converters (MMCs), to improve system reliability and sub-module efficiency, and for maximizing the redundant sub-module value rate. Methods: We establish a set of objective functions using these aims, to obtain the optimal number of redundant sub-modules. To aid in the evaluation of the configuration method, we analyzed the MMC topology and the operational principle of the sub-modules. We present concrete steps for module redundancy optimization based on the redundant protection scheme used with the MMC. Result: The results of simulations modelling the operation of the configuration algorithm prove that the number of redundant sub-modules can be effectively allocated using the proposed method while ensuring the reliable operation of the system.