GIS金属法兰孔特高频信号传播特性研究与外置式发射天线开发

GIS金属法兰孔特高频信号传播特性研究与外置式发射天线开发

内容简介：在未安装内置式特高频(ultra-high-frequency，UHF)传感器的情况下，如何向气体绝缘金属封闭开关设备(gas-insulated metal-enclosed switchgear，GIS)内部注入UHF 电磁波标定信号是目前开展GIS局部放电UHF在线监测系统灵敏度现场校验时面临的关键问题之一。提出了 GIS 外置式UHF电磁波发射方法，即通过盆式绝缘子金属法兰小孔注入标定信号。通过仿真和理论分析研究了UHF电磁波经过小孔时的传播模式和电场结构，通过加脊降低了矩形波导天线的下限截止频率，研制了双脊波导发射天线，在GIS设备上检验了该发射方法及装置的应用效果。研究表明， UHF电磁波以TE10波型为主模经过小孔传播，双脊波导天线的下限截止频率降到了300 MHz，通过它能够向GIS 内部发射300 MHz～1.5 GHz的UHF标定信号。GIS体外式UHF标定信号注入方法可以为GIS局部放电UHF检测仪器现场灵敏度校验提供标定信号源。

Abstract： At present, how to inject UHF electromagnetic wave calibration signal into gas-insulated metal-enclosed switchgear (GIS), in which the built-in ultra-high-frequency (UHF) sensor is not installed, is one of the key problems to be faced with during the field sensitivity calibration of online UHF monitoring system for partial discharge in GIS. An external UHF electromagnetic wave transmitting method for GIS, i.e., the calibration signal is injected via hole on metal flange of disc insulator, is proposed. The propagation mode and the structure of electric field of UHF electromagnetic wave passing through the hole is researched by simulation and theoretical analysis;the lower-cut-off frequency of rectangular waveguide antenna is decreased by adding double ridge and the transmitting antenna with double ridge waveguide is developed, and the application effect of the proposed transmitting method and device are validated on GIS. Research results show that the TE10 wave mode is the dominant mode of EM wave passing through the hole, and the lower-cut-off frequency of double ridge waveguide antenna is decreased to 300 MHz, and the double ridge waveguide antenna can transmit UHF calibration signal within the range from 300 MHz to 1.5 GHz into GIS. The proposed external injecting method for UHF calibration signal can provide calibration signal source for field sensitivity calibration of UHF detective instrument for partial discharge in GIS.

作者：卢启付, 郑书生, 李兴旺, 王亮, 唐志国, 詹花茂,

关键词：全封闭式组合电器, 局部放电, 特高频, 现场校验, 盆式绝缘子, 脊波导, 天线,