Cascade type energy storage converter system capable of suppressing leakage current and control method

The invention discloses a cascade type energy storage converter system with a leakage current suppression function and a control method, and belongs to the technical field of new energy storage, and the cascade type energy storage converter system comprises an I type DC/AC module topological system, a II type DC/AC module topological system and a III type DC/AC module topological system which are sequentially connected in series; the I-type DC/AC module topology system comprises a plurality of I-type DC/AC modules which are connected in series; the II-type DC/AC module topology system comprises a plurality of II-type DC/AC modules which are connected in series. The III type DC/AC module topology system comprises a plurality of III type DC/AC modules which are connected in series. According to the invention, by adding additional switch tubes and matched inductors and capacitors under a traditional H-bridge topological structure, through cooperation of the switch tubes with the S1 switch tube, the S2 switch tub