摘要
针对大量应用电缆线路导致的谐振接地系统单相接地故障时选线正确率下降的问题,提出一种基于计算馈线暂态零序电流重构误差及其低频分量多尺度交叉样本熵的故障选线方法。谐振接地系统单相接地故障时由于消弧线圈补偿作用,故障线路暂态零序电流相位、周期变化均与健全线路不同。利用相位变化不同,通过同步挤压小波逆变换对暂态零序电流进行重构并计算误差。利用周期变化不同计算暂态零序电流低频分量多尺度交叉样本熵。重构误差、交叉样本熵之和均为最大值的线路即为故障线路。大量仿真结果证明,该方法受不同故障条件影响较小,可靠性高,抗干扰性强。
There is a problem that the decrease in accuracy of single-phase grounding fault line selection is because of a large number of cable lines in the resonant earthed system.To solve this,a fault line selection method is proposed based on calculating the reconstruction error of the transient zero sequence current of lines and the multi-scale cross-sample entropy of the transient low frequency bands.Because of the compensation effect of the arc suppression coil,the change of phase and period of transient zero sequence current in a fault line are different from those of a sound line when single-phase grounding occurs in a resonant earthed system.Using the principle of different phase changes,the transient zero sequence current is reconstructed by inverse synchrosqueezed wavelet transforms and the error is calculated.According to the principle of different period changes,the multi-scale cross-sample entropy of the low frequency bands of the transient zero sequence current is calculated.The fault line is determined when the sum of reconstruction errors and the cross sample entropy are at a maximum.A large number of simulation results show that the method is less affected by different fault conditions,and has high reliability and strong anti-interference.
作者
田业
徐天奇
李琰
邓小亮
王阳光
TIAN Ye;XU Tianqi;LI Yan;DENG Xiaoliang;WANG Yangguang(School of Electrical and Information Technology,Yunnan Minzu University,Kunming 650504,China;State Grid Hunan Electric Power Co.,Ltd.,Changsha 410004,China)
出处
《电力系统保护与控制》
CSCD
北大核心
2021年第13期95-104,共10页
Power System Protection and Control
基金
国家自然科学基金项目资助(61761049)。
关键词
配电网
谐振接地系统
故障选线
同步挤压小波变换
多尺度交叉样本熵
distribution network
resonant earthed system
fault line selection
synchrosqueezed wavelet transforms
multi-scale cross-sample entropy
