一种加窗插值FFT谐波分析方法  

An algorithm of windowing interpolation FFT harmonic analysis

作　　者：王宏[1] 

机构地区：[1]中航工业哈尔滨东安发动机(集团)有限公司,黑龙江哈尔滨150066

出　　处：《现代电子技术》2012年第6期71-73,共3页Modern Electronics Technique

摘　　要：由于很难实现同步采样和整周期截断,因此,利用FFT算法分析电网谐波信号时存在频谱泄露和栅栏效应,影响算法的分析精度。加窗插值FFT是抑制频谱泄露和消除栅栏效应的有效方法,在此提出一种基于3项3阶Nuttall窗插值FFT的谐波分析方法,推导了插值系数公式以及各次谐波的频率、幅值和相位的修正公式。对该算法与Hanning窗、Blackman窗插值FFT算法进行Matlab仿真对比研究,验证了该算法具有更高的分析精度。It is difficult to realize the synchronized sampling and integral period truncation. Therefore, the analisis accuracy of algorithm is affected when FFT algorithm is applied to analysis of harmonic signal in power system because of the spectral leakage and fence effect. The windowed interpolating fast Fourier transform （FFT） is the effective method to restrain spectral leakage and eliminate fence effect. A harmonic analysis method based on 3-term 3-derivative Nuttall interpolation FFT is proposed in this paper. The formula of interpolation coefficients, and the estimation formulas of frequency, amplitude and phase of each harmonic are derived. The comparison with the Hanning and Blackman interpolation FFT methods is conducted by Matlab simulation. It verifies that the algorithm has higher analysis accuracy.

关 键 词：谐波 FFT 窗函数 插值 电力系统 

分 类 号：TN911-34[电子电信—通信与信息系统]