Abstract:When using the fast Fourier transform (FFT) for harmonic analysis in the non-coherent sampling, it suffers from two drawbacks: the spectral leakage and picket fence effect, and the harmonic phasor cannot be obtained accurately. The side-lobe characteristics of Rife-Vincent windows are analyzed and an approach for harmonic phasor calculation based on the five term Rife-Vincent(I) window interpolation FFT is proposed. Compared with the traditional window function, the five term Rife-Vincent(I) window with a better curb ability to the spectral leakage, and the picket fence effect can be modified by the double-spectrum-line interpolation algorithm. The simulation results show that, the approach presented in this paper is adapted for the harmonic phasor analysis in the nonlinear circuit, and by using the approach in the non-coherent sampling conditions, the errors of calculating frequency of 22 order harmonics is 5.7×10-11%, as well as that of calculating amplitudes and phases are no more than 5.3×10-7% and 3.1×10-6%.
曾博, 滕召胜, 高云鹏, 王一. 基于Rife-Vincent窗的高准确度电力谐波相量计算方法[J]. 电工技术学报, 2009, 24(8): 154-159.
Zeng Bo, Teng Zhaosheng, Gao Yunpeng, Wang Yi. An Accurate Approach for Power Harmonic Phasor Calculation Based on Rife-Vincent Window. Transactions of China Electrotechnical Society, 2009, 24(8): 154-159.
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