Two-Stage Noise Filtering for DFT-Based Synchrophasor Measurement in Distribution Systems

To improve the operation security and stability of power systems, the distribution-level synchrophasor measurement techniques have been developed rapidly. However, the signals in distribution systems are heavily corrupted by noise which will deteriorate synchrophasor measurement accuracy. This paper preliminarily investigates the noise in distribution systems according to the field measurement results. Then the two-stage noise filtering method is proposed based on the median filter and mean filter. According to the additive problem caused by median filter, the corresponding compensation coefficients are derived. Finally, numerical tests verify the effectiveness of the proposed filtering and compensation method under different conditions.