一种改进型加Kaiser窗电力谐波检测方法

An improved method with Kaiser window for power harmonic detection

为解决FFT高精度谐波分析中插值函数结构复杂,难于直接计算的问题,采用一种用分段三次样条函数拟合插值函数的方法.构造出凯塞窗与三谱线插值相结合插值函数的快速计算公式,该公式结构简单、程序易于实现、分段点处连续、且拟合精度高,能大幅度提高插值FFT算法的运算速度,分析了该方法在实际应用中的可行性,通过分段三次样条曲线拟合和其他拟合方法的相位相对误差和幅值相对误差进行了详细比较.研究结果表明:分段三次样条拟合方法有效的提高了电力系统谐波分析精度.

In order to solve the problem which is difficult to calculate the complex interpolating function in the high precision harmonic analysis of FFT, this paper used a method of fitting section cubic spline function and interpolating function, and combined Kaiser window and three spectral line interpolation to construct a rapid calculation formula, which has simple structure to realize the program easily, the continuous piecewise point, high fitting accuracy and fast operation. This study analyzed the feasibility of this method in practical application, and compared section cubic spline curve fitting with other fitting methods in phase and amplitude relative error by simulation experiment. Results of the study show that cubic spline fitting method effectively improves the accuracy of power system harmonic analysis.