微机保护中3种滤波算法的比较研究

针对信号中非周期分量,频率偏移,分数次谐波对基波分量计算精度的影响,对傅里叶、差分滤波和并联补偿3种滤波算法进行了分析比较。通过大量仿真计算,得出的结论是:并联补偿算法滤除非周期分量的效果最好;傅里叶算法在频率偏移的情况下稳定性要好于其他2种;存在分数次谐波时,差分滤波求得基波分量幅值和相角的误差最小。此结论对工程实际应用具有一定的指导意义。

Comparison and Study of Three Filter Algorithms in Microcomputer Protection

With regard to the accuracy affection during fundamental component calculation caused by aperiodic component, frequency deviation and fractional harmonic in signal, the paper analyzes and compares three filter algorithms of Fourier algorithm, differential filter algorithm and shunt compensation algorithm. The simulated calculation shows that shunt compensation algorithm has a best effect in filtering and eliminating the aperiodic component. The Fourier algorithm has a better stability than the other two algorithms when frequency deviation exists. The error of fundamental component and phase angle calculated by means of differential algorithms is the minimum value when fractional harmonic exists. The conclusion has some certain value of guidance for its application in actual engineering.