摘要
研究基于广域测量系统的电网中故障点的定位方法,对于快速实施电网故障后的自动控制策略具有重要意义。当电网中发生短路故障时,针对在短路故障点产生的暂态扰动变量向电网中广泛传播的特点,提出一种利用暂态扰动变量波形相似度确定电网中故障点的方法。具体作法是:利用广域测量系统获取电网中不同测量点在一段相同时间段内的电压局部极大值和极小值及其对应的时刻数据,利用Hermite函数拟合出电压极大值和极小值曲线并相加,提取各测点的电压暂态扰动变量;利用波形相似度函数计算相邻测点间该扰动变量的传播时差,结合相邻测点间已知的线路长度计算扰动变量行波的波速并确定故障点。通过一个2机无穷大系统的仿真实验,验证了该方法的正确性和准确性。理论分析和仿真实验结果表明,该方法需要安装的测点数量少,不仅可以节省投资,而且可快速确定故障点。
The research on fault location methods for grounding faults in power grids based on wide-area measurement is significant to implement the strategy of automatic quick control. In view of the fact that transient disturbance variables generated at grounding fault points can reflect corresponding transmitting characteristics, a novel location method for grounding faults was proposed based on the waveform similarity of obtained transient disturbance variables in power grid. Specifically the method is： At first, according to the local voltage maximum and minimum values and their corresponding time measured with the same time scales at different places in power grid during the same period, the voltage disturbance variable of each measuring unit was extracted by adding the curves of maximum and minimum fitted by Hermite functiOn. Then, the time delay and velocity of the traveling wave of voltage disturbance variables were calculated by using similarity function and the known line length between two adjacent measuring units. At last the location of the grounding fault was determined by the velocity between two measuring units. The validity and accuracy of the method were proved by a two-generator infinite system simulating model. The theoretical analysis and simulation test show that the required number of measuring units is much less than other methods, the investment can be reduced and the fault location can be quickly determined.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2013年第31期140-146,17,共7页
Proceedings of the CSEE
关键词
电网
故障
扰动变量
定位
广域测量系统
power grids
fault
disturbance variable
location
wide area measurement system （WAMS）
