Li F.-F.,University of Sichuan |
Li F.-F.,Smart Grid Sichuan Key Laboratory |
Yang H.-G.,University of Sichuan |
Yang H.-G.,Smart Grid Sichuan Key Laboratory |
And 3 more authors.
Dianli Xitong Baohu yu Kongzhi/Power System Protection and Control | Year: 2011
This paper proposes a new method to estimate voltage flicker using the discrete Fourier transform, which obtains the parameters of voltage flicker while estimating interharmonics. The proposed method obtains the amplitude, frequency and phase angle of each frequency component using the odd points interpolation correction method, which reduces the leakage while interpolating, based on the specified signal processing recommendations by IEC61000-4-7. According to the concept of voltage flicker, the double-side property of interharmonic pairs converted by voltage flicker is obtained. Considering the maximum perceptible frequency range of the voltage flicker, the frequency range of interharmonics pairs can be obtained. According to the electric power distortion component symbiosis mechanism, we can differentiate the interharmonic pairs from the common interharmonic components, and obtain the parameters of flicker signal by the amplitude modulation with sinusoidal carrier. Comparing with the Square method and Prony method, the simulation results indicate the accuracy and validity of the proposed method, and the odd points interpolation correction method can separate harmonics from interharmonics effectively and restrain the spectral interruption strongly.