Optimal power distribution strategy of hybrid energy storage System considering SOC self-recovery

In the DC miorogrid, the State of charge(SOC) of superoapaoitor and battery in the hybrid energy storage System is easy to exceed the limit during Operation, and the interaction between them will lead to the weakening of SOC recovery effect. In order to solve the above problems, a power seeondary distribution strategy of hybrid energy storage System based on double-layer fuzzy control is proposed. The second layer constraint control is added to the first layer SOC self-recovery control to limit the recovery value, so as to enhance the SOC recovery effect. In view of the problems that the SOC recovery effect is weakened by the virtual capacitor due to its characteristics in the low frequency stage and the coupling effect between the frequency division control and the SOC self-recovery control in the high frequency stage, the seeondary power distribution is optimized. The recovery compensation unit is added in the low frequency stage, and the frequency division control and SOC self-recovery control are decoupled and the decoupling compensation unit is added in the high frequency stage, so as to maximize the recovery effect, prolong the life of the energy storage device and speed up the power response. The relevant model is established in MATLAB / Simulink for Simulation analysis, and the results show that the proposed control strategy can enhance the SOC recovery effect and improve the System stability. © 2025 Electric Power Automation Equipment Press. All rights reserved.