差分与傅氏变换相结合算法在微机电流保护中的应用

Applying the algorithm of FFT with difference data in microprocessor based current protection

采用差分与傅氏变换相结合的计算方法 ,省去模拟滤波电路 ,从带有衰减直流分量的故障电流中提取基波电流 ,进行保护计算和判断 ,具有较高的准确性和可靠性。

It is more accurate and reliable in current protection that basic frequency current is taken from fault current with decaying dc component by use of FFT for difference input data, which eliminates the need of analog wave filter.