摘要
故障时电流互感器饱和很容易引起继电保护等装置误动。分析了电流互感器饱和机制及饱和后的二次电流特征,根据小波Mallat算法,提出了一种基于小波理论的CT饱和检测方法。该方法通过小波Mallat算法提取出二次电流的低频和高频段能量,将二者的比值构成CT饱和检测判据。PSCAD/EMTDC仿真结果表明,该方法在各种故障下均能正确检测CT是否饱和,需要的数据量较小,性能稳定。
The saturation of CT when it was faulted often causes the relay protection incorrect tripping.The saturation mechanism of CT and the secondary current characteristics of saturated CT were analyzed.According to the wavelet Mallat algorithm,a CT saturation detection method based on the wavelet theory was put forward.In this method,the wavelet Mallat algorithm was used to extract the low frequency energy and the high frequency energy of the secondary current,and their ratio is used as criterion for CT saturation detection.PSCAD/EMTDC simulation result shows that under various faults,the method can correctly detect whether the CT is saturated;the method has stable performance,and only lesser data were needed for the detection.
出处
《华电技术》
CAS
2010年第10期18-20,67,共4页
HUADIAN TECHNOLOGY
关键词
电流互感器
饱和
小波
MALLAT算法
current transformer (CT)
saturation
wavelet
Mallat algorithm
