基于太赫兹成像技术的绝缘材料缺陷检测实验研究

Experimental Study on Defect Detection of Insulating Materials Based on Terahertz Imaging Technology

绝缘材料的电气性能和机械性能是输电线路安全运行的重要影响因素。研究使用太赫兹成像技术对绝缘陶瓷、环氧树脂、硅橡胶、石英玻璃四种绝缘材料进行缺陷检测,通过傅里叶变换和理论计算得出了四种材料的光学传播参数谱图。结果表明:有机绝缘材料(硅橡胶、环氧树脂)对太赫兹波具有强烈的吸收,透射率很低,难以在太赫兹领域区分被高电压击穿前后透射率的改变;无机绝缘材料(陶瓷、石英玻璃)由高电压击穿所产生的缺陷在透射率和吸收系数上均有着较为明显的变化。

The electrical and mechanical properties of insulation materials are important factors affecting the safe operation of transmission lines.In this paper,terahertz imaging technology is used to detect the defects of insulating materials such as ceramic,epoxy resin,silicone rubber and quartz glass.The spectra of optical propagation parameters of four materials are obtained by Fourier transform and theoretical calculation.The results show that the organic insulating materials(silicone rubber,epoxy resin)have strong absorption of terahertz wave and low transmittance,so it is difficult to distinguish the transmittance changes before and after the high-voltage breakdown in terahertz field.The defects of inorganic insulating materials(ceramics,quartz glass)caused by high voltage breakdown have obvious changes in transmittance and absorption coefficient.