A compression approach of power quality monitoring data based on two-dimension DCT
Ding Jia-feng · Journal of Central South University(Science and Technology) · 2011
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%.