摘要
输电线路遭受雷击时,往往会造成保护的误动,因此进行过电压识别对研究基于暂态量保护及提高其可靠性都具有十分重要的意义。故障暂态信号的高频分量中包含了非常丰富的故障信息。利用小波包对暂态信号的前1ms信息进行多分辨率分析,得出其在各个尺度的系数。发现故障信号在高频段和低频段的能量分布特点反映了故障的内在特性,利用这个特点对输电线路上的非故障性雷击、故障性雷击以及普通短路故障进行过电压识别,以提高保护的可靠性。大量的ATP仿真实验验证了该判据能可靠、准确地识别出3种过电压。
When transmission lines are struck by lightning,fault operation of protection systems may be occurred.So it is important to study the over-voltage identification and improve the stability of transient protection.Fault transient components contain abundantly fault information.Wavelet packets are applied in multi-resolution analysis to study the prior 1 ms information and work out the coefficient of each scale.It is found that power distribution of fault signals at the high-frequency section and the low-frequency section reflects the inherent characteristic of the fault.On this basis,the over-voltage identification for fault lighting strike,non-broken-down lighting strike and short trouble can be obtained;and the stability of protection systems can be improved.Plenty of ATP simulation experiments prove the reliability of this identification method.
出处
《电力建设》
2011年第3期61-64,共4页
Electric Power Construction
关键词
输电线路
雷击
故障暂态信号
小波包
多分辨率
过电压识别
ATP仿真
transmission line
lighting strike
transient fault signals
wavelet packet
multi-resolution
over-voltage identification
ATP-simulation
