采用电磁时间反转的不同电压等级同杆双回输电线路故障测距  

Fault Location of Double-Circuit Transmission Lines on Same Pole under Different Voltage Levels by Electromagnetic Time Reversal

作　　者：商立群[1] 黄若轩 呼延海 杨晨光 SHANG Liqun;HUANG Ruoxuan;HUYAN Hai;YANG Chenguang(School of Electrical and Control Engineering,Xi’an University of Science and Technology,Xi’an 710054,China)

机构地区：[1]西安科技大学电气与控制工程学院

出　　处：《西安交通大学学报》2020年第1期19-25,41,共8页Journal of Xi'an Jiaotong University

基　　金：陕西省自然科学基础研究计划资助项目(2019JM-544)

摘　　要：针对不同电压等级同杆双回输电线路测距复杂的问题,提出了一种基于电磁时间反转理论的故障测距方法。建立了线路的故障附加网络,推导了经时间反转后的故障电流有效值,并分析了电磁时间反转理论应用于输电线路故障测距的适用性。记录线路两侧故障电流变化的情况并用新六序分量法解耦线路,对经解耦后得到的两侧同向正序电流分量进行小波分解,提取两侧电流突变量,对两侧电流突变量进行时间反转并叠加。假设在输电线路多处发生故障,计算出各个故障点处的电流有效值,最大电流有效值对应的距离即为故障距离。利用ATP-EMTP软件搭建了不同电压等级同杆双回输电线路仿真模型,采用Matlab进行编程验证。仿真结果表明:所提方法不受过渡电阻和故障相角的影响;当采样频率为1 MHz时,在不同故障类型情况下测距结果的相对误差低于0.57%,所提方法测距精度高;测距结果的相对误差会随着采样频率的上升而降低。Aiming at the problem of complex ranging of double-circuit transmission lines on the same pole under different voltage levels,a fault location algorithm following electromagnetic time reversal theory is proposed.An additional network of line fault is established,the effective value of fault current after time reversal is deduced,and the applicability of electromagnetic time reversal theory to fault location of transmission line is analyzed.The fault current changes on both sides of the line are recorded and the line is decoupled by the new six-sequence component method to obtain the same-direction positive sequence current components on both sides.Wavelet decomposition is used to decouple the positive-sequence current in the same direction on both sides,and the fault current features on both sides is obtained.Then,the current mutations on both sides are time-reversed and superimposed.Assuming that there are multiple faults in the transmission line,the current effective value of each fault is evaluated,and the distance corresponding to the maximum current effective value is the fault distance.A power transmission model under different voltage levels of the same double-circuit line was built in ATP-EMTP software.The simulation results show that the algorithm is not affected by transition resistance and fault phase angle,and when the sampling frequency is 1 MHz,the relative error of ranging results is less than 0.57%under different fault types.The relative error of ranging results reduces with the increasing sampling frequency.

关 键 词：不同电压等级同杆双回输电线路 故障测距 电磁时间反转 新六序分量法 小波分解 

分 类 号：TM721.2[电气工程—电力系统及自动化]