GIS支柱绝缘子上未知缺陷的示踪研究

Research on the Tracing of the Potential Defect on GIS Post Insulators

较之实验室人为模拟的缺陷试品而言,选用实际的含缺陷的GIS绝缘子进行实验研究更能够反映变电站现场的局部放电情况,并更为真实地模拟现场闪络事故的产生过程。但是实际绝缘子上所含的缺陷通常是未知的,因而需要先对缺陷在绝缘子上的位置进行示踪,以了解缺陷的具体形式,为后续的进一步的研究提供基础。文中以一个含有未知缺陷的GIS支柱绝缘子为例,通过光电效应、红外成像、不同气体条件下的放电特性变化等多种手段尝试示踪缺陷的具体位置,最终通过高精度断层扫描确定了缺陷的具体形式。该研究过程对于实际绝缘子上的缺陷排查具有重要的参考意义,也为缺陷的放电机理研究和GIS绝缘子制造工艺的改进提供了依据。

Compared with the artificial specimens made in the laboratory,the practical GIS insulators with potential defects can reflect the partial discharge(PD)situation and the process of the flashover accident in substations more veritably.However,unlike the artificial specimens,the defects on practical insulators are usually invisible,which makes it to be traced first,in order to locate its position on the insulator and reflect its pattern,before further investigation could be carried out.In this paper,a practical GIS post insulator with potential defect is tested,and several tracing methods,including the photoelectric effect,the infrared imaging,and the variation of the PD characteristics in different gas conditions,are used to find the position of the defect on the insulator,and the problem is eventually solved by the high resolution computed tomography.The tracing process shown in this paper will make significant reference sense on the checking of the defects on practical GIS insulators,and also provides basis to the research on the mechanism of the discharge and the improvement of the manufacturing technique of GIS insulators.