检测GIS局部放电的小型化多频带复合天线

Miniaturized Multi-band Compound Antenna for Detecting Partial Discharge in GIS

为了对气体绝缘全封闭组合电器(GIS)局部放电的超高频信号进行检测,设计了一种用于检测GIS局部放电的多频点宽频复合天线。首先,通过对复合天线进行小型化、宽频化原理分析,实现天线的小型化;然后,运用矢量网络分析仪对实物天线进行驻波比实测研究;最后,在实验室搭建GIS局部放电测试系统对天线进行实测研究。结果表明:设计研究的天线兼具多频带、小型化和高增益的特性,在0.75~0.90 GHz、1.23~1.48 GHz、1.78~2.12 GHz、2.42~2.79 GHz的频段范围内,其驻波比(VSWR)小于2,具有较宽的频带范围,能够记录局部放电的大部分信息;随着频率的增加,天线增益也在逐渐变大,天线最高增益可达6.5 dB,可有效接收微弱的特高频信号;研究结果表明,设计的天线特性良好,可用于GIS局部放电的现场监测。

In order to detect the UHF signal of partial discharge(PD)in gas insulated switchgear(GIS),a multi-frequency point broadband compound antenna was designed for detecting PD in GIS.Firstly,the principle of miniaturization and broadbandization of the compound antenna was analyzed to realize the miniaturization of the antenna.Then the voltage standing wave ratio(VSWR)of the antenna was tested by vector network analyzer.Finally,a GIS partial discharge test system was built in the laboratory to conduct the actual measurement study on the antenna.The test results show that the compound antenna has the characteristics of multi-band,miniaturization and high gain;it has a VSWR of less than 2 with a wide frequency range and can record most of the partial discharge information in the frequency range of 0.75 GHz to 0.90 GHz,1.23 GHz to 1.48 GHz,1.78 GHz to 2.12 GHz and 2.42 GHz to 2.79 GHz.with the increase of frequency,the antenna’s gain gradually increases with a maximum gain reaching up to 6.5 dB,which can effectively receive weak UHF signals.It is concluded that the designed antenna has a good performance and is quite promising for PD on-line detection applications.