基于曲流技术的多频段特高频传感器的研制

Development of Multi-band UHF Sensor Based on Meandering Technique

变电站局部放电（PD）检测特高频传感器的工作频率范围为300~1 500 MHz,为避开该频段内手机信号等诸多外界干扰,基于环形天线原理和曲流技术设计了一种新型多频段全向特高频传感器。通过仿真和实测研究了该传感器的局部放电检测性能,并将其与宽频传感器的局部放电检测性能进行对比。结果表明,该传感器的工作频段为480~520、800~850、1 100~1 150 MHz,覆盖了电晕放电、沿面放电、自由金属微粒放电3种典型的局部放电缺陷信号的主要频率范围;且具有体积小、近似全向测量和灵敏度高的特点。该传感器能较好地检测各种类型的放电信号,满足变电站局部放电检测及定位要求。

The operating frequency of UHF sensors for detecting partial discharge （PD） of transformer in substation ranges from 300 MHz to 1 500 MHz generally. In order to avoid the interference in this frequency band, such as signals from mobile phones, we proposed a multi-band omni-directional UHF sensor based on the loop antenna theory and the meandering technology. The PD detection performance of the proposed sensor was tested by simulation and experiments, and it was compared with that of a broadband sensor. It is shown that the multi-band sensor can operate in bandwidth ranges of 480-520 MHz, 800-850 MHz, and 1 100-1 150 MHz, thereby it covers the main spectra of signals from three typical kinds of PD, namely, corona discharge, surface discharge, and free particle discharge. This multi-band sensor is also advanced for its small size, omni-directional measurement, and high sensitivity. It is capable of detecting many kinds of PD signals while meeting the requirements of PD detection and PD location in substations.