基于小波理论的供电设备局部放电在线测试仪的研究

摘要

The part discharge measure is one important means that power equipment ensure trustiness running.The local measure discharge is faced with strong interfere.At present, the data processing is mainly based on fourier transform arithmetic.It is very difficult to obtain an ideal result for no calm wave signal of part discharge due to its localization.It has introduced one testing instrument of power supply equipment based on wavelet analysis,the application of Mallat tower decompose arithmetic based on much distinguish analysis. It has adopted sampling frequency select 20MHz.Thus,discharge signal can obtain from narrow strip interfere.The inside and outside distinguish problem of discharge pulse with the time-frequency analysis tool has been solved by one frequency steip phase rule of discharge shape inside,outside and in HVTC′s connection gad line.%局部放电检测是保证电力设备可靠运行的重要手段之一 ，现场检测放电面临强烈干扰；目前，采用的数据处理方法主要是基于傅立叶变换算法，由于该算法的局限性，对局部放电这样的非平稳突变信号，较难获得理想结果．本文介绍了一种基于小波理论的供电设备局部放电在线测试仪，采用基于多分辨分析的Mallat塔式分解算法，采样频率选用20MHz，可快速地从较强的狭带干扰中获取放电信号．并根据内外放电脉冲在设备的外壳接地线中的形状与在高、低压侧电流互感器的接地线中的形状在某一频带上相位规律，借助于小波分析这种时—频分析工具，解决了内、外部放电脉冲的鉴别问题．