Optimal supercapacitor pack sizing for modular multilevel converter with integrated energy storage system
Résumé
Energy Storage Systems (ESS) are a necessity for the future power distribution network and so their use is expected to grow. Usually, the implementation of an ESS is achieved by massive battery storage made of long connected row of cells, potentially leading to reliability issues. This paper investigates how to integrate a scalable ESS unit taking advantage of the modularity of modular multilevel converters (MMCs). It aims at presenting a detailed sizing methodology of supercapacitor (SC) pack in a way that the overall cost of the solution can be minimised. The proposed converter topology is briefly introduced. The results reveal that introducing an additional power converter into a submodule (SM) is mostly interesting for designing the ESS and for managing the ESS energy.