超/特高压输电线路宽频窗短时窗行波差动保护方法  

Wide-frequency and Short-time Window Based Traveling Wave Differential Protection Method for EHV/UHV Transmission Lines

作　　者：雷傲宇 董新洲[1] LEI Aoyu;DONG Xinzhou(State Key Lab of Control and Simulation of Power Systems and Generation Equipment(Department of Electrical Engineering,Tsinghua University),Haidian District,Beijing 100084,China)

机构地区：[1]电力系统及发电设备控制和仿真国家重点实验室(清华大学电机系)

出　　处：《中国电机工程学报》2019年第23期6826-6835,共10页Proceedings of the CSEE

基　　金：国家重点研发计划项目(2016YFB0900600)~~

摘　　要：行波差动保护(traveling wave differential protection,TWDP)基于分布参数线路的行波传输不变性,行波差动电流(traveling wave differential current,TWDC)天然地考虑了分布电容电流和传输时延,在超/特高压(extra-/ultra-highvoltage,EHV/UHV)输电线路保护中具有性能优势。行波差动保护在实际应用中面临2项制约:一是有限的硬件水平和通信条件,二是电容式电压互感器传变频带窄,使得现有行波差动保护只采用了窄频窗的故障行波信息,无法兼具快速性和可靠性。为此,该文提出采用宽频窗短时窗的故障行波信息,首先分析区内外故障时行波差动电流的频率分布,然后据此提出一种新型行波差动保护方法,动作快速可靠。仿真验证表明,该方法所需采样率适中,不要求实时通信,灵敏度高,具备选相跳闸能力,因此具有良好的应用前景。Traveling wave differential protection(TWDP)is based on the traveling wave transmission invariance of the distributed parameter line.Traveling wave differential current(TWDC)takes inherently the capacitive charging current and transmission delay into account,so TWDP gains performance advantage among protection techniques for extra-/ultra-highvoltage(EHV/UHV)transmission lines.There exist two restrictions for TWDP in practical application:the limited hardware and communication level,and the limited bandwidth of coupling capacitor voltage transformers.The aforementioned two factors make it impossible for existing TWDP methods to have both the rapidity and reliability due to the only usage of a narrow-frequency window of fault traveling wave information.This paper proposed to utilize a wide-frequency and short-time window of fault traveling wave information.First,the spectral distribution of the TWDC was analyzed for internal and external faults.Then,a novel quick and reliable TWDP method was presented.Simulation cases verified that the proposed TWDP method required no real-time communication,needed adequate sampling rate,operated sensitively,and had the ability of single-pole tripping mode.Therefore,the proposed TWDP method has good application prospect.

关 键 词：输电线路 超/特高压 继电保护 行波差动保护 行波 

分 类 号：TM77[电气工程—电力系统及自动化]