Wide-area protection scheme for distribution networks based on 5G communication and zero sequence quantities

Aiming at the performance degradation of traditional zero sequence current protection in complex distribution networks caused by the integration of distributed generation, this paper proposes a novel wide-area protection scheme based on 5G communication. By deploying deeply integrated primary and secondary switches to collect zero sequence voltage and current amplitudes in real time, the data is transmitted to an intelligent protection center via the 5G network. A two-layer criterion is established: “locating the fault area at the node with the maximum voltage amplitude → identifying the fault point on the line with the maximum current amplitude.” This scheme requires only amplitude comparison, eliminates the need for strict synchronization, and integrates the low-latency advantages of 5G with the measurement capabilities of primary and secondary equipment. Simulations demonstrate that the proposed protection scheme accurately operates even with a transition resistance of 500Ω and achieves selective fault isolation even when communication is partially interrupted, outperforming traditional zero sequence current protection in terms of operation speed.