Study on Detection Method of Electrical Shock Current Based on Sliding Window and Wavelet Transform

Abstract:

With the popularization of the rural electricity utilization, the rural electric safety was still an immediate problem to be solved. It was difficult to exactly detect and judge electric shock signals in the summation leakage current on the low-voltage electric power grid. A detection method of electrical contact signals based on sliding window and wavelet multi-resolution method was proposed. Under the different signal-to-noise ratio level, the summation leakage current was reconstructed by wavelet decomposition reconstruction algorithm. According to the characteristic of the slow change of the normal leakage current and the rapid change of the electric shock current within a short time, the electric shock current were extracted from the restructured summation leakage current signal by sliding window method. The mean square error and correlation analysis between the extracted signal and the actual testing results were studied. The analysis results show that the proposed method could identify electric shock current in the summation leakage current among noise, and its detection precision was superior to single sliding window method.

• Periodical: Advanced Materials Research (Volumes 860-863)
• Pages: 2035-2039
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.860-863.2035
• Online since: December 2013
• Authors: Chun Lan Li*, Song Huai Du, Zhai Shi, Juan Su
• Keywords: Electric Shock, Electric Shock Current Detecting, Sliding Window, Wavelet Transform (WT)

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