State Decomposition-Based Privacy-Preserving Distribution Control for ESSs in DC Charging Station

In DC charging stations, the average consensus-based secondary control is widely used to allocate output currents of energy storage systems (ESSs). However, with this explicit state exchange, the initial state of ESS has the risk of being leaked. Hence, a state-decomposition-based consensus control (SDCC) is proposed to realize current distribution in DC charging station while protecting the initial states of nodes. By using the state-decoupling strategy, the state variable of one node is divided into two sub-states assigned random initial values. In the new consensus protocol, these two sub-states are used for external and internal interactions, respectively. One of the sub-variables is used for external consensus control so that the true initial state of the node is protected. Another sub-variable is used for internal dynamic control to achieve global consensus. The consensus finite-time convergence and privacy-preserving ability of the proposed method are proved by theoretical analysis. Finally, each state variable performs feedback control of the variable for precise current distribution. Finally, the privacy-preserving ability of SDCC is verified through various case studies.