改进的时域同步插值算法在基于TDA谐波和间谐波测量中的应用

Application of Improved Time-Domain Interpolated Synchronous Algorithm in Harmonic and Interharmonic Measurement Based on TDA

时域同步插值可以解决非同步采样下多周期FFT谐波与间谐波测量的精度问题,但多周期窗口化会引起插值点跑位且插值计算量较大。文中提出了一种改进的时域同步插值算法,通过计算理想插值点的跑位数来确定其对应插值区间,并对相应的步长比例因子进行修正,解决了跑位问题;采用递推的方法求解步长比例因子,减少了插值运算量。仿真结果表明,该算法结合时域平均(TDA)运用于谐波和间谐波测量,非同步采样情况下仍有着较高的精度。

Time-domain interpolated synchronous algorithm can solve the precision problem in harmonic and interharmonic measurement based on fast Fourier transform （FFT） when the sampling is asynchronous. However the ideal interpolating point may run out and the calculation quantity will be bigger because of the long window. An improved time-domain interpolated synchronous algorithm is presented in the paper. It solves the ＇run out＇ problem by correcting the step-length section factor and the interpolating interval. Also the step-length section recursive method. The simulation results show that factor reduces the calculation quantity through the the improved algorithm combined with time-domain averaging （TDA） holds a high precision in harmonic and interharmonic detection though the sample sequence is asynchronous.