摘要
±800 kV特高压直流(ultra high voltage direct current,UHVDC)输电线路在雷击故障或非雷击故障下,因有故障电流入地的集中参数通路,保护安装处观测到的电压波形在5 ms时窗内幅值骤降,出现过零点,且多次与零轴相交,其故障后的暂态分量与极电压值相关度较小,时窗内的电压均值也较小。在雷击未造成故障情况下,由于不存在故障电流入地集中参数通路,雷电引起的冲击响应相对于极电压值较小,电压波形在5 ms时窗内围绕各极直流电压轴线上下交替变化,并逐渐衰减至极电压轴线,其电压暂态分量与极电压轴线相关度较大,时窗内的电压均值接近于该极电压轴线值。将时窗前2 ms电压采样值直接进行相关度计算,后3 ms采样值直接进行电压均值归一化计算,将两特征进行可拓融合来实现雷击干扰识别,兼有故障选极功能。仿真结果表明该算法有效。
For the lightning stroke fault or ground fault on ±800 kV ultra high voltage direct current （UHVDC） transmission line, because there is a fault current lumped parameter access to the earth, the voltage waveform observed at the protection position decreases suddenly and crosses repeatedly the zero line in 5 ms time window. The correlation degree of transient component and pole voltage and the average voltage value in the time window are both small. For no-fault lightning stroke, there is no fault current accessing to the earth, so the impulse response caused by lightning is much less than the value of the pole voltage. The voltage waveform at the protection position changes up and down around the direct voltage line in the 5 ms time window and decays to the pole voltage line at last. The correlation degree is calculated using the former 2 ms samples and the average value is calculated using the next 3 ms samples, these two characteristics are inosculated by extension theory and information fusion to identify the non-fault lighting and select the fault pole. Simulations results show that the algorithm is effective.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2011年第7期102-111,共10页
Proceedings of the CSEE
基金
国家自然科学基金项目(50977039
50847043
90610024
50467002
50347026)
云南省自然科学基金重点项目(2005F0005Z)
云南省科技攻关项目(2003GG10)~~
关键词
电力系统
±800KV直流
雷击干扰
相关度
均值
可拓融合
采样值计算
power system
ultra high voltage direct current（UHVDC）
lightning disturbance
correlation degree
averagevalue
extension fusion
samples calculation
