Analysis of action mechanism of positive sequence fault component directional element considering energy storage access

When the energy storage system is connected to the AC distribution network, the action characteristics of the fault component direction element are different from other new energy systems due to its special control strategies and working modes. Under the same fault condition, the different charging and discharging modes of the energy storage system will lead to different operating characteristics of the positive sequence fault component direction element. Based on the control strategies and working modes of the energy storage system, this paper focuses on the phasor characteristics of the positive sequence voltage and current before and after the symmetrical fault of the AC side line connected to the energy storage system, and analyzes the action mechanism of the positive sequence fault component direction element. Finally, the correctness of the theoretical analysis is verified by PSCAD simulation.