基于DWT的自适应电能质量信号压缩及消噪  

Adaptive power quality signals compression and denoising based on DWT

作　　者：李鹏[1] 杨洪耕[1] 

机构地区：[1]四川大学电气信息学院,四川成都610065

出　　处：《继电器》2004年第20期5-9,共5页Relay

摘　　要：应用信息论的AMDL(ApproximateMinimumDescriptionLength)判据,针对动态电能质量扰动(DPQD)信号压缩和消噪问题,提出了一种新的利用离散小波变换(DWT)的数据压缩和消噪算法。针对不同噪声水平和不同信号类型,这种算法具有数据自适应能力,其不需要进行任何先验的参数设置(例如阈值设置)和主观判断就能确定保留小波系数的最佳个数,并能根据信号动态选择小波基。计算实例表明MDL判据能够在信号保真度与信号压缩效率之间找到最佳的契合点。This paper introduces a new data compression and denoising technique for short time voltage change signal via discrete wavelet transform (DWT) and information-theory based approximate minimum description length criterion (AMDL). This algorithm has data-adapted capability for different noise levels and signal sorts. Without any parameter setting (such as thresholding) or subjective judgments, it can select the 'best' number of wavelet-retained coefficients and 'best' wavelet basis according to dymamic signals. Results of computation prove that the MDL criterion can give the best compromise between the fidelity of the signal and the efficiency of signal compression.

关 键 词：信号压缩 消噪 DWT 自适应 小波系数 离散小波变换 数据压缩 动态电能质量 信号保真度 判据 

分 类 号：TM711[电气工程—电力系统及自动化] TN911[电子电信—通信与信息系统]