Abstract: A harmonic analysis algorithm of windowed interpolation FFT based on zeroing spectral-line amplitudes is proposed to analyze the harmonics of complex power network signals. The complex power network signals are analyzed until the harmonic analysis is completed by zeroing the amplitudes of the maximum spectral line and the three spectral lines on its left and right sides found in the discrete spectrum. Measurement accuracy is studied when the fundamental frequency is stable and influence of fundamental frequency fluctuation on the measurement accuracy is analyzed with simulation. The analysis results of the EAST experimental data verify the feasibility and high accuracy of the method.

Key words: Zeroing spectral-line amplitudes, Windowed interpolation FFT algorithm, Harmonic detection, High accuracy

摘要： 提出了一种基于谱线幅值归零的加窗插值 FFT 谐波检测方法用于分析复杂电网信号中的各次谐波。 该检测方法将每一次在离散频谱中找到的最大谱线及其左右两侧的数根谱线幅值归零，直到各次谐波分析完毕。 通过仿真实验分析了在基波频率稳定时对模拟信号的测量精度，研究了基波频率波动对谐波分析的影响。通过对EAST 实验数据的分析，验证了该谐波检测方法的可行性和高精度性。

关键词: 谱线幅值归零；加窗插值 FFT；谐波检测；高精度