加窗插值FFT的电网谐波分析算法研究

Power System Harmonic Measurement AnalysisBased on Windows and Interpolated FFT

快速傅立叶变换(FFT)在测量电力系统谐波时存在的频谱泄漏问题会产生较大误差,从而影响分析结果。加窗插值算法可以有效减小泄漏,改善谐波幅值、相位测量准确度。选择电力系统中较为常用的Hanning窗和Blackman-Harris窗插值法,通过仿真对算法的精度和复杂性进行比较分析,对算法进行了进一步修正,使得谐波分析结果与实际情况更为接近。

There is some leakage spectrum when measuring the harmonic with fast Fourier transform(FFT),which would lead to some error.Windowed interpolation is an effective algorithm to reduce the leakage,and improve the measurement precision of harmonic amplitude and phase.Interpolation algorithm on Hanning window and Blackman-Harris window,which are widely used in signal analysis,are introduced in this paper.Comparison and analysis on precision and complexity of the proposed algorithm are implemented,and the simulat...