基于正序阻抗比的有源配电网不对称短路故障区段定位方法  

Location method of asymmetric short-circuit fault for active distribution network based on positive sequence impedance ratio

作　　者：黄飞 肖扬 戴健 欧阳金鑫[2] 刘佳 王大彪 HUANG Fei;XIAO Yang;DAI Jian;OUYANG Jin-xin;LIU Jia;WANG Da-biao(State Grid Chongqing Electric Power Research Institute,Chongqing 401123,China;State Key Laboratory of Power Transmission Equipment&System Security and New Technology(Chongqing University),Chongqing 400044,China;State Grid Chongqing Yongchuan Power Supply Company,Chongqing 402160,China)

机构地区：[1]国网重庆市电力公司电力科学研究院,重庆401123 [2]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆400044 [3]国网重庆市电力公司永川供电分公司,重庆402160

出　　处：《电工电能新技术》2022年第12期44-53,共10页Advanced Technology of Electrical Engineering and Energy

基　　金：国家自然科学基金联合基金项目(U1866603);国网重庆市电力公司科技项目(SGCQDK00DWJS2100189)。

摘　　要：随着分布式电源(DG)大量接入配电网,传统配电网向有源配电网方向转变。然而,受DG随机性、多态性的影响,配电网故障类型多样、故障特征复杂多变,现有故障定位方法存在一定的局限性。因此,本文提出了一种基于正序阻抗比的有源配电网不对称短路故障定位方法。首先,分析了不对称短路故障下DG的输出特性,建立了逆变型DG故障等值模型,建立了各自不对称短路故障下有源配电网的等效电路,分别推导了DG上游故障与DG下游故障时DG输出电流的解析表达式;进而分析了DG上游故障与DG下游故障两种情况下的正序等效阻抗特征与差异,构建了新的配电网不对称故障定位特征量,提出了适用于DG接入的配电网不对称故障定位方法。理论和仿真分析表明,该方法不受不对称短路故障类型、DG功率变化、负荷大小的影响,能够准确定位故障区段,且原理简单、边界清晰、整定容易,具有较高的可靠性和适应性。With a large number of distributed power sources(DG)connected to the distribution network,the traditional distribution network is transformed into an active distribution network.However,affected by the randomness and polymorphism of DG,the fault types of active distribution network are diverse,and the fault characteristics are complex and changeable.The reliability and sensitivity of existing fault location methods are limited in the active distribution network.Therefore,this paper proposes a location method of asymmetric short-circuit fault for active distribution network based on positive sequence impedance ratio.First,the DG output characteristics under asymmetric short-circuit faults are analyzed,and an equivalent model of inverter interfaced DG is established.Furthermore,the characteristics and differences of the positive sequence equivalent impedance between the upstream fault and the downstream fault of the DG are analyzed.A new asymmetric fault location characteristic quantity of distribution network is constructed.And a location method of asymmetric short-circuit fault in distribution networks suitable for DG access is proposed.Theoretical analysis and simulation results show that the method is not affected by asymmetric short-circuit fault types,DG power changes,and load sizes,and can accurately locate faulty sections.It has simple principles,clear boundaries,easy setting,and high reliability and adaptability.

关 键 词：配电网 分布式电源 短路故障 故障定位 阻抗比 

分 类 号：TM77[电气工程—电力系统及自动化]