含分布式光伏接入的有源配电网故障区段定位新方法

A Novel Fault Section Location Method of Active Distribution Network With the Integration of Distributed Photovoltaic

大量分布式光伏的接入改变了传统配电网的网架结构,传统配电网络由单侧电源供电的辐射状网络变为多端电源供电的网络,这导致传统故障区段定位方法难以准确识别出故障区段。为此,提出一种不受分布式光伏接入影响的配电网故障区段定位新方法。首先,提取故障后配电网线路各区段两端的正序电流幅值变化曲线并进行归一化处理;随后,引入弗雷歇距离算法比较各区段两端正序电流幅值波形的相似度,依次计算出各区段的弗雷歇距离,数值最大的区段即判定为故障区段;最后,搭建含分布式光伏接入的配电网仿真模型,对所提方法的性能进行验证。仿真结果表明,无论何种类型的故障,所提方法均不受分布式光伏接入的影响,定位精度高,耐过渡电阻能力好,具有良好的工程适用性。

The integration of a large number of distributed photovoltaics(PVs)has changed the network structure of traditional distribution networks.The traditional distribution network has changed from a radial network powered by a single power source to a network powered by multiple power sources,which makes it difficult for traditional fault section localization methods to accurately identify the fault section.A new method for fault section location of distribution network was proposed which can not be affected by distributed PVs.Firstly,the amplitude change curves of positive sequence currents at both ends of each section of the distribution network line were extracted and normalized.Then,the Frechet distance algorithm was introduced to compare the waveform similarities at both ends of each section,calculating the Frechet distance of each section in sequence,and the section with the highest value was determined as the faulty section.Finally,a distribution network simulation model with distributed PVs was constructed to verify the performance of the proposed method.The simulation results show that regardless of the type of fault,the proposed method is not affected by distributed PVs,has high positioning accuracy,good resistance to transition resistance,and good engineering applicability.