Research on BESS Participating in Power System Primary Frequency Regulation Control Strategy Considering State-of-Charge Recovery

Aiming at the problem of frequency instability under high-penetration of renewable energy in power system at present, a primary frequency modulation control strategy of energy storage device considering the State-of-Charge (SOC) recovery is proposed. Firstly, the influence of renewable energy grid-connected on the frequency characteristics of the power system is considered and a dynamic model of primary frequency modulation is established. Secondly, in order to reduce the dependence of energy storage on the movement selection of frequency critical value and deviation, fuzzy control is used to adaptively adjust and allocate the coefficients of virtual inertia control and virtual droop control method. Then, considering the self-recovery of the SOC, the state of the SOC is maintained as far as possible, and the frequency modulation ability of the SOC is enhanced. Finally, a regional power network model is taken as an example to build a simulation model to compare different control strategies under step and continuous disturbance conditions, and the effectiveness of the proposed strategy is verified.