采用过电压波形识别的单相接地暂态过电压抑制方法  

Suppression Method of Single-phase Grounding Transient Over-voltage Using Recognition of Over-voltage Waveform

作　　者：代姚[1] 孙才新[1] 袁涛[1] 司马文霞[1] 冉锐[1] 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400030

出　　处：《高电压技术》2010年第5期1136-1142,共7页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2009CB724504)~~

摘　　要：运行经验表明消弧线圈在中性点非有效接地的电网正常运行和故障时的参数整定、调节困难,常常难以兼顾两种工作状态,限制了消弧线圈的应用。而随着坚强智能电网的建设,为实现调节控制故障的发展需求,快速准确地对弧光接地过电压进行抑制显得非常必要。为此,提出了采用过电压波形识别,有选择性地投入消弧线圈对单相接地暂态过电压进行抑制的方法,并在考虑消弧线圈自身损耗电导和线路对地电导的基础上,推导了电网对地电容电流实时计算的方法,从而实时准确地调节消弧线圈参数。依据该方法,建立了某110 kV变电站的EMTP仿真模型,分析了线路参数和负载变化对消弧线圈参数调节的影响以及有选择性地投入消弧线圈时对暂态过电压的抑制效果。仿真结果表明该抑制方法对电网正常运行状态影响小,且发生单相接地故障时对暂态过电压有很好的抑制效果。Petersen-coil is often used to suppress arc grounding over-voltage,but operation experience has revealed that parameter adjustment of petersen-coil is complicated,so the application of petersen-coil is limited.With the construction of a strong intelligence network,in order to realize the needs of the development of regulating and controlling faults,suppressing grounding over-voltage quickly and accurately is necessary.Consequently,we proposed the method of switching on petersen-coil selectively to suppress single-phase grounding transient over-voltage based on over-voltage waveform recognition.We also deduced a method of calculating capacitive phase-to-earth current in real time which takes account of arc-suppression coil loss conductance and line-to-ground conductance.This method can guarantee accurate and instant adjustment of petersen-coil.A 110 kV substation of the EMTP simulation model was constructed,and the effect of line parameters and changing load on adjustment of coils was analyzed.The simulation results show this measure not only suppresses transient over-voltage but also has little effect on other normal operation of power grid.

关 键 词：单相接地 暂态过电压 抑制方法 对地电容 消弧线圈 容性电流 实时计算 

分 类 号：TM864[电气工程—高电压与绝缘技术]