Distributed Secure Balancing Control for Battery Energy Storage Systems Under Privacy-Preserving Mechanisms

This paper deals with the privacy-preserving-based distributed secure balancing control problem for battery energy storage systems (BESSs) in a microgrid. A novel distributed consensus algorithm is proposed based on the state decomposition strategy and the homomorphic cryptography technique, under which the state-of-charge (SOC) balancing issue is addressed amid potential privacy leak threats. By decomposing the state of the modified SOC for BESSs based on the number of neighboring BESSs, the privacy of each BESS’s state is safeguarded, provided that the BESS has at least one neutral neighboring BESS. Each homologous substate exchanges information directly, and non-homologous substates exchange information using a homomorphic cryptography algorithm. A weighted approach is used to ensure that the sum of the homologous substates aligns with the group decision value, thereby maintaining consistency among these homologous substates. The effectiveness of the proposed method is validated through a series of illustrative simulation experiments. Note to Practitioners—The integration of BESSs into microgrid poses challenges in maintaining SOC consistency, attributed to inherent parameter differences among BESS units. To meet these challenges, a distributed control algorithm is proposed, aiming to stabilize charging and discharging states across these systems. The use of public internet infrastructure for BESS communication raises privacy concerns, as it is vulnerable to security breaches. To mitigate the risk of eavesdropping and enhance data security, robust privacy protection mechanisms are integrated into the proposed methodology, ensuring the secure integration of BESS into microgrid systems. The results of this study provide a simple but useful algorithms achieve SOC consistency between BESSs, while performing privacy preservation.