Hybrid Energy Storage Black Start Control Strategy Based on Super Capacitor

Addressing the issue of efficient, economical, and reliable operation of a single lead-acid battery (LAB) black start system in complex scenarios, a hybrid energy storage system (HESS) black start scheme based on super capacitors (SCs) is proposed. The proposed solution mainly includes two aspects: an integrated structure and a control strategy. A topology structure with a direct parallel output on the AC side is adopted, and the SC is directly connected to the AC side of the LAB in the current source mode. Compared with traditional DC side access schemes, it can cope with large surge currents by a small capacity, and the economy of the HESS black start system has been effectively improved. In order to improve the dynamic characteristics of the black start control system, a self-adaptive control strategy based on the virtual synchronous generator (VSG) and model predictive control (MPC) is proposed. Based on the small signal disturbance model, the influence of the system parameters on stability was analyzed, and the control parameters are adjusted according to the angular velocity and frequency deviation. A generator recognition model at the ms level was constructed, and the set reference current according to the power level is brought into the MPC to track the reference current. Compared with existing methods, it can effectively suppress the disturbance of the black start system, and the fast responsiveness and stability of the control system is improved. Finally, real operational data is compared and analyzed. The results indicate that the proposed control strategy can accurately identify different black start scenarios, with lower configuration costs and good dynamic performance.