分布式电源并网对继电保护的影响研究

Study on the Effect of Distributed Power Source Combined Network on Rely Protection

DG的并网改变了传统配电网中辐射状的网络拓扑结构,从单电源供电结构转变成多电源供电结构,给继电保护带来了一些不利影响。分析了DG并入不同母线位置及非母线情况下,发生金属性或者非金属性故障给系统继电保护带来的影响。DG的并网会影响保护的灵敏度,造成保护拒动或者误动,改变保护范围。分析了DG并网对重合闸的影响,DG并网可能造成重合闸失败或者非同期合闸时产生冲击电流损坏元器件,对含DG网络的继电保护设计有指导作用。

The Combined network of DG has changed the topological strtucture of the network of radiation in traditional distributed network.The powersupply structure from single source has been changed into multiple power sources,leading to some unfavourable effects of relay protection.The paper analyzes the effect of meatl or nonmetal fault on the system relay protection under the condition of DG be merged into different busharpositions and nonbusbars.The combined network of DG can effects protective sensitivity,resulting in refused action or malfunction of protection,thus changing protecting range.Analyze the effect of DG on the combined network closing,the combined netwrok of DG may lead to reclose failure or impulse current damaging components when nonsynchronous closing,which has directive function to the relayprotection of DG netwrok.