分布式电源对配电网保护的影响分析及改进

Consequence Analysis of Distributed Generation on Distribution Network Protection and the Improvement

针对分布式电源(distributed generation,DG)接入配电网后会使原来简单的单电源辐射网络变成复杂的多电源网络,导致原有配电网馈线保护出现灵敏度降低、拒动、误动等情况,从而给配电网的运行和控制造成多方面影响的问题。从DG的容量、类型、位置等因素对配电网馈线保护可能产生的影响进行定性分析,并针对现有的配电网保护提出改进方案,包括加装方向元件、修改定值或采用纵联差动保护等。

The simple singlepower radiation network may turn into complex multipower networks after connection of dis tributed generation （DG） into distribution networks, resulting in sensitivity reduction of feeder protection, failure to opera tion and unwanted operation, which therefore influences operation and control of distribution networks in many aspects. Impact on feeder protection is quantitively analyzed in terms of capacity, type and location of DG; furthermore, present im provement scheme for distribution network protection, including installing directional elements, modifying fixed value or a dopting crosslinked differential protection is put forward.