Research on Application Setting Scheme of Distribution Line Non-communication Protection

Aiming at the actual situation of multiple feeders on the same bus and multiple branches on the lines in the distribution network, this paper proposes a setting scheme for the distribution line non-communication protection considering the influence of branch line faults and adjacent line faults. In the scheme, the mainline protection and branch line protection cooperate. Branch lines are equipped with quick break protection to ensure the unity of protection selectivity and rapidity. The action delay of non-communication undervoltage protection co-ordinates with overcurrent protection section I of adjacent line. The voltage setting value of non-communication undervoltage protection coordinates with the fault phase voltage variation on the bus in case of fault at the end of the protection range of overcurrent protection section I of adjacent line to solve the misoperation of undervoltage protection in case of adjacent line faults. Simulation results show that the proposed protection setting scheme is not affected by adjacent line faults, and the mainline faults and branch line faults are selective.