Research on Hybrid Energy Storage Input Strategy and SOC Equilibrium Control of Energy Storage Module Based on Versatile Static Synchronous Machine

In this paper, the equivalent circuit models of the distributed supercapacitor(SC) energy storage system(ESS) and the centralized lithium battery ESS in the versatile static synchronous machine(VSSM) are established, and when short circuit faults occur on the AC and DC sides of VSSM, an input action strategy of the hybrid energy storage system(HESS) composed of supercapacitors and lithium batteries is designed according to the different charging and discharging features of the power and energy energy storage modules. In addition, this paper proposes a state of charge (SOC) equalization control strategy for energy storage modules (ESM). Finally, the above strategies are verified in a four-machine system based on the electromagnetic transient simulation software PSCAD/EMTDC.