基于波形距离系数的逆变站近区交流线路保护方向元件  

Waveform Distance Coefficient Based Directional Element for AC Transmission Line Protection Near Inverter Station

作　　者：冀肖彤 柳丹 熊平 陈玉 杨霖 文明浩[3] JI Xiaotong;LIU Dan;XIONG Ping;CHEN Yu;YANG Lin;WEN Minghao(State Grid Hubei Electric Power Co.,Ltd.,Wuhan 430077,China;State Grid Hubei Electric Power Co.,Ltd.,Research Institute,Wuhan 430077,China;School of Electrical and Electronic Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]国网湖北省电力有限公司,湖北省武汉市430077 [2]国网湖北省电力有限公司电力科学研究院,湖北省武汉市430077 [3]华中科技大学电气与电子工程学院,湖北省武汉市430074

出　　处：《电力系统自动化》2024年第1期140-149,共10页Automation of Electric Power Systems

基　　金：国家电网有限公司科技项目(4000-202222070A-1-1-ZN)。

摘　　要：逆变站仅有单回出线时,若逆变站近区交流线路发生故障,逆变站的复杂特性导致传统方向元件难以判别故障方向。文中对逆变站近区交流线路故障特征进行了分析。然后,指出了交流线路电流与交流边界元件电流时域变化量之间的相似特征,提出了利用测量电压、电流推算交流边界元件电流的电磁暂态计算方法。最后,利用时域中的交流线路电流与交流边界元件电流之间的波形距离系数在正方向和反方向故障下的差异,提出了一种新的方向判别原理,并通过大量仿真对其性能进行了验证。仿真结果表明,所提方向元件能准确识别故障方向,具有较高的可靠性和灵敏度。When the inverter station has only one outgoing line,if the fault of the AC line near the inverter station occurs,the complex characteristics of the inverter station make it difficult for the traditional directional element to identify the fault direction.In this paper,the fault characteristics of AC transmission lines near inverter stations are analyzed.Then,the similarity between AC line current and current variation of the AC boundary element in time domain is proposed.And an electromagnetic transient calculation method is also proposed to calculate current of AC boundary elements by measuring voltage and current.Finally,based on the difference of the waveform distance coefficients between AC line current and AC boundary element current in time domain under forward fault and reverse fault conditions,a new fault direction discrimination principle is proposed.And its performance is verified by extensive simulations.The simulation results show that the proposed directional element can accurately identify the fault direction and has high reliability and sensitivity.

关 键 词：交直流混联系统 逆变站 方向元件 电磁暂态计算 波形距离系数 

分 类 号：TM721.3[电气工程—电力系统及自动化] TM773