Modeling equalization circuits with digraph

There is no effective tool introduced at present to analyze those complicated and various charging/discharging equalization circuits of series connected battery bank, which limited the development of this technology. This paper proposed a novel method with directed graph to model the circuits. Diagrammatic representation of the perfect equalization structure is derived, and the models of four basic circuits and various derived structures are presented. The isomorphism between the models is indicated with the comparison. And also, the possible maximum efficiency of each structure is worked out. The extensibility and reliability are also concerned. It shows that the derived structure may be the most promising one in the future. The method advanced here allows ignoring the effects of various material components while analyzing, and also favors deeper research and further optimization.