一种非整周期采样的高精度FFT电压闪变算法

摘要

根据传统IEC闪变测量原理,考虑谐波和电网频率可能造成的误差,提出了一种针对非整周期采样的高精度的闪变计算方法.算法核心是对非整周期采样的电网电压波形加布莱克曼窗进行实序列FFT,然后进行双谱线插值修正计算结果,对得到的调幅波信号加权得到瞬时闪变视感度.加窗可以减轻频谱的泄露,插值可以对结果进行补偿,实序列FFT可以提高运算速度.通过仿真证明该方法有效且易于实现.%Considering the traditional flicker measurement principle and the possible error of harmonic, a new high accuracy flicker measurement algorithm aimed to non - integer - period sampling is proposed. The core algorithm is that a BlacAman window is applied to the Non - Integer - Period grid power signal. A further amendment is made to the result according to double spectral line interpolation. Lastly, the instantaneous flicker visual sensitivity is obtained by weighting the amplitude - modulated wave. By the window technique, spectral leakage can be relieved. Interpolation can compensate the result and improve the anti - interference ability. The real sequence FFT can improve the speed of operation. Simulation results demonstrate the effectiveness of the proposed algorithm which can be easily realized.