Active distribution network protection scheme based on area current direction

摘要

After the distributed generation is connected to the distribution network, the topology of the unidirectional power supply of the traditional distribution network has been changed, which may lead to the problem of voltage limit and bidirectional power flow. The traditional current protection method is no longer applicable. The fault current characteristics of the inverter interfaced distributed generation under PQ control and the influence of the distributed generation on the traditional current protection technology are analyzed. On this basis, an active distribution network protection scheme based on the area current direction is proposed. The distribution network is partitioned and the fault area is judged by collecting the current fault component direction. The relevant circuit breaker is controlled to complete the isolation of the fault area. Finally, the proposed protection scheme is simulated in PSCAD / EMTDC. The simulation results show the adaptability of the protection scheme to the active distribution network.