Adaptive virtual resistance strategy based on black start for grid-forming photovoltaic-energy storage system

With the widespread integration of renewable energy sources, the black-start capability of power systems is becoming increasingly important. During the black-start process, transformer input and load access may cause overcurrent phenomenon, which not only threatens the stability of the power system, but also may lead to equipment damage. In order to effectively suppress this phenomenon, a novel grid-forming adaptive virtual resistance strategy is proposed in this paper. The strategy dynamically adjusts the virtual resistance size by monitoring the inductor current and current change rate of the system in r eal time, and quickly seeks the optimisation through NPDOA. Finally, the proposed control strategy is verified using the Simulink simulation experiment platform. The experimental results show that compared with the fixed virtual resistance control strategy, the strategy can further suppress the overcurrent phenomenon and improve the frequency stability and dynamic response performance of the system.