基于四阶Hanning自乘窗FFT三峰插值的电能计量新算法

为了进一步提高加窗插值算法的计算准确度,文章提出一种新型五项余弦组合窗函数—四阶Hanning自乘窗函数,并基于该窗函数拟合推导出了加窗FFT三峰谱线插值的通用幅值、相位和频率修正公式;利用这些通用插值修正公式,提取出被测电压、电流信号基波和谐波的幅值、相位和频率参量,进而精确计算出基波电能和谐波电能。仿真结果表明,由于该窗函数具有较好的主瓣和旁瓣性能,可有效地抑制频谱泄露和栅栏效应的影响,故基于它构建的电能计量新算法具有较高的计算准确度。

A New Algorithm for Electric Energy Measurement based on four order Hanning self-multiplication window triple-spectrum-line interpolation FFT

In order to further improve the calculation accuracy of the windowed interpolation algorithm,this paper pro-poses a new five-terms cosine window function,four-order Hanning self-multiplication window function,based on this, window function and three spectral lines interpolation correction formula,the general amplitude,phase and frequency interpolation correction formula are derived.We can extract the amplitude,phase and frequency parameters of funda-mental wave and harmonic in the measured voltage and current signal by these general interpolation formulas, and then,we can calculate the electric energy of fundamental wave and harmonic accurately.The simulation results show that,because of the window function has better main lobe and side lobe performance,which can effectively suppress the influence of spectrum leakage and fence effect,so based on this window function,the new algorithm for computing electric energy has higher accuracy.