基于小波包分析的录波数据压缩原理

本着对数据采样率、压缩率要求较高的原则，提出了将最优小波包基变换应用到故障行波数据的压缩上。对故障暂态信号采用更高频率进行采样，利用小波可变时频窗及检验信号奇异性的优点进行信号分解．在此基础上，利用小波包最优基对高频段即细节部分再分解而获得局部最优信息的优点进行故障数据的综合压缩。EMTP依频线路上仿真．并分析了压缩后数据的实用性，说明用该原理实现的录波器压缩数据．在失真率较小的情况下，得到较高的压缩比。‘

Theory of power system fault data compression based on wavelet packet

To access to high sampling speed and compression ratio,the wavelet packet transform theory is applied to data compression of traveling wave. The fault transient signals are sampled with higher speed and the data is decomposed by wavelet transform that has characters in time frequency localization and data singularity detection . The wavelet packet is then used to decompose the high - frequency part more deeply to obtain the locally best information for fault data compression . The EMTP simulation in frequency - dependent model and the analysis of the decomposed data prove that higher compression ratio with smaller distortion is achieved based on this theory.