The Allocation And Setting Of Protective Relaying And Automatics In Tongling Electric Network With Small-Scale Generating Units

It's has led to difficulties in settings of protective relaying because of in-grid small-scale generating units'operation,which has threatened safety of power system, protective relaying and automatic apparatus. When transmission line is tripped off, it would lead to 110kV bus loss-of-voltage in the substation and loss-of-load. Insecurity emergency has appeared many times in Tongling electric network because of in-grid small-scale generating units'operation. In order to avoid the occurrence of these insecure accidents and enhance the reliability of power supply,study should be put on the allocation and settings of protective relaying in this area.It has a great practical value and academic meaning.The paper analyses hazard of operation with single- at the moment 110kV transmission line tripped off,if small-scale generating couldn't be cut-off. By analyzing the influences on system and especially on the allocation and settings of protective relaying.,this paper consummates the allocation project and setting principle,and then gives a set of remote breaker cut-off project in order to enhance the reliability of power supply.