UHF局部放电信号包络检波电路设计与实现

Design and implementation of UHF partial discharge signal envelope detection circuit

气体绝缘组合电器局部放电产生的特高频信号频率大多分布在300 MHz~1.5 GHz,直接对特高频原始信号进行采样和分析,要求系统必须具备较高的采样率,导致需要处理传输的数据量巨大,成本高昂,工程应用困难。而气体绝缘组合电器局部放电产生的特高频信号的包络波形同样携带着大量的放电缺陷特征信息,对提取的包络波形进行采样处理,一方面可以大大降低对系统采样率的要求,另一方面也保留了局部放电缺陷大部分的特征信息。根据气体绝缘组合电器局部放电产生的特高频信号特性,设计实现了一种适用于气体绝缘组合电器局部放电产生的特高频信号的包络提取检波电路,实测结果表明,该检波电路响应速度快、惰性失真小,提取的包络波形与特高频原始信号的轮廓基本一致,较好地保留了气体绝缘组合电器局部放电所携带的特征信息。

The frequency of UHF signal generated by partial discharge of gas insulated switchgear is mostly distributed in 300 MHz—1.5 GHz.If the original UHF signal is directly sampled and analyzed,the system must have a high sampling rate,which leads to a huge amount of data to be processed and transmitted,high cost and engineering application difficulty.The envelope waveform of UHF signal generated by partial discharge of gas insulated switchgear also carries a lot of discharge defect feature information.Sampling the extracted envelope waveform,on the one hand,can greatly reduce the requirements of the system sampling rate;on the other hand,it also retains most of the feature information of partial discharge defect.According to the characteristics of UHF signal generated by partial discharge of gas insulated switchgear,an envelope extraction detection circuit for UHF signal generated by partial discharge of gas insulated switchgear is designed and implemented.The experimental results show that the detection circuit has fast response speed,small inertia distortion,and the extracted envelope waveform is basically consistent with the contour of UHF original signal,and better retains the feature information carried by GIS partial discharge.