【作者】 蒋建玲；

【导师】 李成榕；

【作者基本信息】 华北电力大学（北京） ， 高电压与绝缘技术， 2003， 硕士

【摘要】 本论文的工作是利用超高频(UHF)法研究GIS试验模型中局部放电的特征。 通过与大华无线电厂合作，研制了超高频传感器，其主要由天线、超高频放大器、高通滤波器、宽带检波器等组成。通过大量的性能测试和试验证明，超高频传感器既能够有效的避开空气中的电晕干扰，又能够方便有效的测量到GIS内部局部放电的信号。 建立了GIS局部放电测量系统，其中包括：常规局部放电测量系统、超高频检波测量系统和放电频谱测量系统等，通过测量系统得到了GIS内局部放电的超高频暂态信号波形、检波信号波形、工频相位分布、频谱特征以及常规视在放电量等特征。 论文重点研究了GIS内几种典型缺陷的局部放电特征，其中包括：高压导体上的尖刺，高压导体接触不良、地电位的接触不良，盆式绝缘子上的自由金属颗粒群、固定金属颗粒、单个金属颗粒，筒体表面自由金属颗粒。试验结果表明，不同缺陷类型的局部放电在其检波信号波形、局部放电工频相位分布和超高频频谱特征是有所不同的，可以依据这些特征对GIS内的局部放电类型进行识别。更多还原

【Abstract】 An experimental model is performed in Lab to find the ultra-high frequency (UHF) features of the partial discharges (PDs) signals in Gas Insulated Substations (GIS).A UHF sensor is designed and fabricated, which mostly consists of antenna, UHF amplifier, high pass filter, and broadband wave detector. Experiments show that the UHF sensor can effectively avoid the effect from corona discharges in air, and can conveniently detect PD signals in GIS.A GIS PD measuring system is established, including a conventional PD measurement system, UHF detecting system and a PD spectrum system. We can obtain PD signal characters by this system, such as UHF transient signal waveforms, UHF demodulating signal waveforms, the PD phase angle in AC, PD spectrum, and discharge quantities.The thesis focuses on some typical patterns of PD in GIS in the ultra-high frequency features. The patterns include the protrusion on the high voltage conductor, high voltage conductor’s and grounding conductor’s bad contacts, free metal particles, fixed metal particles, single metal particle on the insulation spacers and free metal particles on the tube surface in the GIS. The test results show that different patterns of PD correspond to different demodulating signal waveforms, the PD phase angle in AC, and spectrum characteristics. Therefore the PD patterns can be recognized by the UHF characters of different PD signals in GIS.更多还原