Power Allocation Strategy for Battery Energy Storage Power Station Considering SOC Equalization

Abstract

In order to ensure the operational safety of the battery energy storage power station (BESPS), a power allocation strategy based on fast equalization of state of charge (SOC) is proposed. Firstly, BESPS is divided into charging group and discharging groups, which can reduce the response number of battery energy storage system (BESS). Then, the charging and discharging power of the BESS is formulated as a Sigmoid function in relation to the SOC. Furthermore, a differentiated mapping of SOC is proposed to augment the distinctions in power allocation weights among BESS with varying SOC levels. This approach can enhance the rate of SOC convergence in BESS, thereby preventing their withdrawal from operation due to excessive SOC. Finally, the effectiveness of the proposed power allocation strategy is verified by simulation.