Measurement of Dielectric Loss Angle Based on Wavelet Threshold Denoising and Least Squares

Abstract:

Dielectric loss angle is the effective means to determine the status of the high voltage equipment.Influenced by power grid frequency fluctuation and white noise, the measurement accuracy of traditional method of dielectric loss angle such as harmonic analysis method, cannot meet the demand.A new methodbased on wavelet threshold denoising and least squares is presented in this paper. Firstly, harmonic wave and white noise are eliminated by improved wavelet thresholddenoising, Second, the fundamental wave of voltage and current signal is extracted by mean of least square method, then we can get dielectric loss angle.Simulation and calculation are validated in the different values of frequency fluxion and whtie noise.Comparing with harmonic analysis method,the result show the feasibility and effectiveness of this method.

• Periodical: Applied Mechanics and Materials (Volumes 220-223)
• Pages: 2160-2164
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.220-223.2160
• Online since: November 2012
• Authors: Hai Wen Chen, Fu Jiang Mo
• Keywords: Dielectric Loss Angle, Improved Wavelet Threshold Denoising, Least Square (LS)

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