摘要
介绍了容性设备介质损耗因数在线监测的基本原理,介绍了高频脉冲信号和随机信号的来源及其对测量结果影响。并提出了采用基于数理统计原理的剔点处理和平滑处理两种预处理方法来消除高频脉冲和随机信号对于监测结果的影响,取得了较好的结果。对于各种方法的分析对比可以知道,如果单纯采用傅立叶变换对监测信号进行处理,效果不甚理想,而如果对数据先进行剔点处理和平滑处理,然后采用傅立叶变换来提取电流和电压信号的基波相角,得到的tanδ值则十分接近真实值,而且其方差较小,没有出现奇异点。故而该方法的准确性和可靠性较高。
The principle of on- line monitoring on dielectric loss tangent of capacitive equipment is introduced as well as the source of high - frequency pulse and random signals Milch affect the measurement result. Two preprecess methods based on statistical principle, which can eliminate the affection to the measurement result from high - frequency pulse and random signals, are mentioned. As a result of the analysis and comparison of various methods, it can be seen that it is not good for disposing the monitoring data with Fourier transsform barely. And if the data is preproeessed with the two methods based on statistical principle before distilling the fundamental wave phase angles of current and voltage signals with Fourier transfoml, the numerical value is obtained wliich is very close to the real value of tanδ, and its variance is smaller, no singular point appeared. Therefore, tiffs method is more exact and reliable than other methods mentioned.
出处
《四川电力技术》
2007年第5期49-51,57,共4页
Sichuan Electric Power Technology
关键词
在线监测
介质损耗因数
预处理
数理统计原理
傅立叶变换
on- line monitoring
dielectric loss tangent
preprocess
statistical principle
Fourier transfoml
