基于频谱分辨率自适应的双插值DFT谐波分析方法

Two-weighted interpolation DFT harmonic analysis algorithm based on spectrally-resolution adaptive

插值FFT作为一种常用的电力系统谐波分析方法,在抑制谱间干扰、宽带噪声等方面存在一定不足。文章提出了一种基于频谱分辨率自适应的双插值DFT谐波分析方法。该方法基于窗函数、插值方法对算法谱间干扰误差和宽带噪声误差的影响机理,通过频谱分辨率自适应以抑制基波对谐波计算的频谱干扰,并通过倍频逆推求整次谐波,避免插值计算谐波带来的误差。仿真结果表明,所提出的算法相比于双插值FFT和三插值FFT算法具有更高的计算精度。

The multi-weighted interpolation FFT is a commonly algorithm of harmonic analysis for power systems.However,there are deficiencies in suppressing inter-spectral interference and broadband noise.This paper proposes a novel two-weighted interpolation DFT harmonic algorithm based on spectrally-resolution adaptive.Based on the influence mechanism of window function and interpolation method on inter-spectral interference error and wide-band noise error of the algorithm,the spectral interference of the fundamental wave to the harmonic calculation is adaptively suppressed by the spectral resolution,and the whole harmonic is obtained by the multiplication of the frequency,so as to avoid the error caused by the interpolation calculation of the harmonic.The simulation results verify that the algorithm has a better precision compared with two-weighted interpolation FFT and three-weighted interpolation FFT algorithm.