数字量输入式合并单元的白噪声处理

为了提高数字化采样的可靠性及精确度，白噪声问题一直是工业界和学术界的研究热点。首先，结合智能变电站的应用实例，给出了电子式互感器的输出波形，并对白噪声分量进行频谱分析。进而，考虑滤波效果、算法稳定性、延时时间等因素，设计了相应的数字滤波器，并给出了滤波参数及处理结果。最后，结合非周期分量衰减时间常数、最大峰值瞬时误差等指标，分析和评估了滤波算法对暂态性能的影响。分析结果表明，数字滤波算法可以使白噪声削弱一半以上，且不会影响暂态性能。

White noise processing in merging unit of digital input

To improve the reliability and accuracy of digital sampling, the problem of white noise has become the research focus in the industrial and academic circles. First of all, the output waves related to merging unit of digital input are given, while the component of white noise is analyzed, together with a specific application of smart substation. Additionally, the relative digital filter is designed, considering the processing effect, stability and time delay, while the parameters and processing results are given. Finally, the influence of transient characteristics is researched and estimated, combined with the indexes of decay time constant and maximum peak instantaneous error. The results show that the digital filter could decrease more than half of the white noise, improve the sampling waveform, and would not influence the transient characteristics.