Abstract:Aiming at the impact of uneven distribution of power consumption on power grid, the low utilization rate and short life of some energy storage batteries at the present stage, a scheme of modular energy storage battery interconnection is proposed. Battery modules are formed by combining voltage-up and voltage-down circuit, equalization circuit and energy management control to replace traditional batteries directly in series and parallel. Battery modules are connected to transformers through PCS circuit for grid connection. In the study of PCS, a control strategy combining quasi-proportional resonance control and proportional integral control is adopted. Under the control of two-phase stationary coordinate system, no static error tracking is ensured, and voltage and current double-loop control is used to ensure the accuracy and stability of grid connection. Finally, the research is simulated by MATLAB experiment, and the grid-connected current meets the requirements, which proves the feasibility of the research. The grid-connected decompression of the user-side transformer to alleviate the pressure can be carried out through the battery module.