中文摘要：

为处理大量的电能质量监测数据,提出一种基于分块二维DCT算法的电能质量监测数据的压缩方法。该方法按周期倍数将电能质量监测数据进行截断和重组,构成二维表示的电能质量监测数据。对二维电能质量监测数据按照8×8矩阵进行分块,并对每个分块矩阵进行二维DCT变换。将所有分块矩阵中同一位置的元素提取出来构成分块重排矩阵,每个分块重排矩阵中的元素处在同一个能量级。根据分块重排矩阵的平均能量对重排矩阵进行量化,得到的量化矩阵和保留的分块重排矩阵作为压缩的结果数据。仿真结果表明：当均方误差为3.89%时,压缩比可以达到82.8%。

英文摘要：

A compression approach of power quality monitoring data based on two-dimension discrete cosine transform（DCT） was presented to deal with huge data about power quality event detection.The monitoring data was truncated and recomposed in multiple cycles to transform the one-dimension data into the two-dimension data,which was a matrix in essence.The matrix was divided into some sub-blocks,which were all 8×8 matrices.These matrices were performed by two-dimension DCT.The elements at the same location of all sub-matrices formed a new matrix,and the elements were at the equivalent energy level.The energy levels of new matrices were measured by average energy,and quantitative matrix was obtained by a threshold of average energy.The new matrices and quantitative matrix were used to represent the monitoring data set.The simulation result shows that the data compression ratio can reach 82.8% when the mean square deviation is 3.89%.