本文提出了一种采用六项余弦偶次幂窗三峰插值的算法来对电网谐波进行检测与分析。该算法通过分析电网信号加窗后傅里叶变换的频域表达式，利用谐波频点附近的三根离散频谱的幅值确定谐波谱线的准确位置，进而得到电网谐波的相关参数频率、幅值及相位的计算公式，最后再对其进行加权修正，从而进一步的提高检测的准确度和有效性。- this paper proposes an approach for power network harmonic detection and analysis based on six even order cosine window and triple-spectrum-line interpolation. Through analyzing the adding window signal fourier transform in the frequency domain expression, using amplitude of three discrete spectrum near the harmonic frequency point to determine the accurate position of the harmonic spectrum and get the calculation formula of related parameters of the power network harmonic such as frequency, amplitude and phase, the algorithm further enhances the accuracy and effectiveness by using weighted correction.