In response to the detection defects and resistance disturbance impact problems of traditional passive islanding protection technology in photovoltaic substations

a new operation and control strategy for islanded DC microgrids under hybrid energy storage is analyzed and summarized. Firstly

a DC microgrid topology with photovoltaic

hybrid energy storage

and SVG anti-islanding units is constructed

relying on layered power control of batteries and supercapacitors to smooth out high and low frequency power fluctuations in the grid

and combined with dynamic droop control to stabilize bus voltage. At the same time

micro-current active disturbance identification technology has been adopted to eliminate the blind spots of traditional islanding detection. Through fault protection and maintenance

dual condition adaptive control is broken

and a passive and active dual islanding prevention system is constructed. This strategy effectively improves the stability of island microgrid operation and the reliability of island protection in the substation area.