改进单峰谱线插值算法在谐波检测中的应用

Application of Improved Single-Peak Spectral Line Interpolation Algorithm in Harmonic Check

快速傅立叶变换是电力系统谐波分析常用方法,但FFT在非同步采样和非整数周期截断的情况下存在较大误差,无法获得较精确的谐波参数。在此基础上现有单峰谱线插值算法可以有效改善谐波数据准确度。但是算法的分析精度很大程度上取决于信号频率校正系数的计算精度且计算量大,利用专用电能计量芯片ATT7022B可准确测量出基波频率,在此基础上推导出的简化算式,极大降低了单峰谱线算法的计算量,并利用多项式逼近获得了幅值修正公式,显著提高了谐波检测的精度。

FFT is a commonly used power system harmonic analysis method, and it will bring on high error under nonsynchronous sampling and truncated non-integral period. Thus moreaceurate harmonic parameter values cannot be obtained. Based on this, the existing single-peak spectral lines interpolation algorithm can effectively improve the accuracy of harmonic data. However, the precision of this algorithm is determined by the precision of the corrected frequency coefficient. Because the fundamental wave frequcncy can be measured directly by A3TT022B, the single-peak spectral lines interpolation algorithm is improved in this paper so the corrected coefficient is easy to get and the polynomial approximation method is also employed to obtain simple formulas for amplitude correction.