为满足电能质量数据存储与传输的需要,基于图像平滑算法、二维离散小波变换以及图像多级树集合分裂编码算法提出了一种电能质量数据压缩新方法。将一维电能质量数据转换为二维矩阵以挖掘电能质量数据的循环间冗余性;应用数字图像平滑技术对二维变换后所得到的电能质量图像矩阵进行平滑处理以有利于二维小波变换编码;结合二维离散小波变换、图像多级树集合分裂编码以及DEFLATE编码算法对电能质量数据进行压缩。仿真实验结果表明,相对现有的电能质量数据压缩方法,所提出的方案不仅能更有效地压缩电能质量数据(同等压缩比的情况下,信噪比更高),而且还可以根据实际需求通过对压缩码率的控制灵活调节电能质量数据压缩性能。
To meet the requirements for power quality data storage and transmission,a data compression method based on the image smoothing algorithm,the two-dimension discrete wavelet transform and the coding algorithm of image SPIHT(Set Partitioning In Hierarchical Tree) is proposed.The one-dimensional power quality data are transformed to the two-dimensional matrix to dig the redundancy of cyclic power quality data and the obtained two-dimensional image matrix treated by the image smoothing algorithm simplifies the two-dimensional wavelet transform coding.Combined with the two-dimension wavelet transform,image SPIHT coding algorithm and DEFLATE coding algorithm,the power quality data are compressed.The simulative results show that its signal-noise ratio is higher than that of existing data compression methods under same compression ratio and its compression performance is flexibly regulated by controlling the bit rate according to practical requirement.