基于B样条小波预处理的短窗算法

提出了可滤除偶次和分次谐波的Ｂ样条小波滤波算法，将经过滤波预处理的短窗傅氏算法和传统傅氏算法进行了比较。从分析结果可看出，经过２次分解与重构的信号接近于基波，减少了因傅氏算法不能滤除偶次谐波或非整次谐波而带来的误差。在同传统方法作比较后，提出了用基于Ｂ样条预处理的２种短窗算法分别代替半波傅氏算法和全波傅氏算法的方案从而可提高保护动作的快速性和可靠性。

SHORT-WINDOW ALGORISMS BASED ON THE PREPROCESSING OF B-SPLINE WAVELET

Anovel algorithm that can filter even number and non-integer number harmonics usingB-spline wavelet is introduced in this paper. The results show that the signal is veryclose to the fundamental wave after decomposition and reconstruction for 2 times incomparison with the conventional Fourier algorithm,so the error is enormously reduced.After compared with the conventional way，a new method is provided that replacingrespectively half-wave and full-wave Fourier algorithm with short-window algorithms basedon B-spline wavelet. The proposed algorithm can improve the speed and reliability ofrelaying protection.