Compression Algorithm of Power Quality Data Based on Segmented Discrete Cosine Transform
Yin Wei-min · Low Voltage Apparatus · 2011
Compression was preprocessing work before transmission or analysis of the power quality(PQ) event data.The segmented discrete cosine transform(DCT) was applied to PQ data compression.Simulation results showed that the compression performance of DCT was better than that of wavelet transform(WT) for stable PQ data,such as harmonics.For transient PQ,such as short duration voltage variation,WT was used to detect the singularity of the signal firstly.Then signal was divided into segments by singularities and DCT was performed subsequently.The experimental results indicated that segmented DCT of short duration voltage variation signal outperformed the results obtained by global DCT.