Optimal Components Selection for a DAB Model of CHB Converter

Abstract

This paper proposes a sizing procedure for the cascaded H-bridge (CHB) converters integrating the battery energy storage system at the submodule level through a dual active bridge (DAB) converter. The suggested methodology considers different parameters, such as the adopted modulation strategies and the topology of the DAB converter employed. Three possible DAB configurations are considered: the one using only full-bridges (for both sides), the one using only half-bridges (for both sides) or a mixed configuration using half-bridge on one side and full-bridge on the other side. After determining the system parameters, the solution capable of reaching the required efficiency target at the minimum cost is obtained. The cost analysis and the efficiency evaluation are carried out considering a dataset containing almost 1000 semiconductor devices whose datasheets have been taken from the manufacturers' websites. The procedure has been developed in the framework of a collaboration with NHOA Energy and its effectiveness is demonstrated by sizing a 1 MW-CHB converter combined with energy storage systems at 11 kV.