小波分析在高压线路行波保护中的应用

The Line Protection Based on Travelling Wave and Wavelet Tranform

特高压电网的发展对继电保护提出了更高要求,传统反映工频量的保护动作速度难以再提高,基于暂态故障分量的行波保护研究再度受到广泛重视。在介绍线路行波保护原理特点及其发展的基础上,分析了小波变换应用于高压线路行波选相、行波保护、重合闸和行波故障测距中的研究成果,指出了小波变换应用和行波保护发展中需要注意的问题,展望了行波保护的发展前景。结果表明:利用小波变换可以提取行波信号,准确定位行波到达时刻,提取波头极性和行波幅值大小,从而为行波保护的实现奠定了坚实的数学基础。

UHV transmission line requires the new technology for relay protection. It is difficult to increase the speed of protection based on power frequency . The study of the line protection based on travelling wave is renewedly regarded. In this paper, the protection based on traveling wave is introduced, the applicationof wavelt transform in the protection is analyzed, the problems and study direction are pointed out. The study show that the applying wavelet transform can pick-up traveling wave signal, nicely confirm its arrived time, pick-up its wave-head polarity and amplitude,therefore mathematics foundation for realizing the protection based on traveling wave is established. The protection based on traveling wave and wavelet transform will be widely applied to UHV transmission line along with the technology development of DSP and optics transformer.