离散小波变换用于电能质量扰动数据实时压缩

DWT APPLICATION TO REAL-TIME COMPRESSION OF POWER QUALITY DISTURBANCE DATA

电力系统中与电能质量扰动相关的监测数据规模在短时间内迅猛增加 ,其庞大的数据容量给存储带来了很大的麻烦 ,亟须在存储前对其做压缩处理。文中提出了电能质量扰动数据的实时离散小波变换 ( DWT)法 ,该方法能够实时地对电能质量扰动数据信号进行多分辨分析 ( MRA) ,在各尺度上筛选与扰动相关的小波变换系数并进行保留 ,从而实现实时压缩的目的。该方法还可以利用保留下来的小波变换系数进行几乎无信息损失的信号重构来复原原始电能质量扰动数据信号。

In power system, rapid volume increasing of the monitoring data, concerned with certain power quality disturbance in a short time, causes much trouble when saving. Thus a compression algorithm needs to be carried on the data before being saved. A real time method so called discrete wavelet transform (DWT) method is proposed. Through applying real time multi resolution analysis (MRA) to the data, selecting and saving wavelet transform coefficients of each scale related to certain disturbance, real time data compression can be reached. These coefficients can be used to reconstruct the original data with little information lost. Feasibility of this real time method has been verified in a practical project.