基于ARM的电力变压器UHF局部放电监测系统

为了无失真地采集超高频检测中所需的有用信号,笔者介绍了一种利用混频原理将电力变压器UHF局部放电信号进行降频变换,较好地采用ARM微处理器设计了一款现场信号调理与采集系统,在μC/OS-Ⅱ操作系统基础上编写用户软件对信号进行处理和运算,提取了局部放电信号的各类相位分布谱图和统计算子。实验结果表明,笔者设计的基于混频技术的信号调理单元,很好地达到了UHF窄带时域信号的降频变换作用,为局部放电模式识别提供了各种可靠真实的特征参数。

ARM-based UHF Partial Discharge Monitoring System for Electric Power Transformer

In order to collect useful signal without distortion for ultra-high frequency detection,this paper proposed a signal conditioning and collecting system using the mixing principle to realize frequency-shift of UHF partial discharge in power transformer by virtue of ARM microprocessor.Customer software was coded based onμC/OS-Ⅱoperation system to process and calculate the signal Various phase distributions and statistical operator were extracted.The results show that the signal conditioning unit based on the mixing principle can reach a very good down-changing function of time-domain signal with UHF narrow band, and it can supply a variety of exact and credible characteristic parameters for partial discharge pattern recongnition.