A control method for battery energy storage system based on MMC

A battery energy storage system based on modular multilevel converter is proposed in this paper, which has many advantages, including easy expansibility, simple structure and high reliability. The system is capable of compensating active and reactive power simultaneously, applied for high capacity and high power situation. The mathematical model of system is built and its circulating current suppressing control method is introduced in this paper. The circulating current is analyzed in situation of different power output, and circulating current suppressing method is proposed. The simulation model of the system is built in PSCAD/EMTDC, the feasibility of proposed control method is validated by simulation results.