An indicator of a defect in a high-voltage insulating structure

Abstract

To monitor the insulation of high-voltage equipment, different kinds of devices, including in situ ones, are used. This paper considers the possibility of using optical indicators—light emitters mounted on the insulation structure of high-voltage lines and substations—as such devices. The principle of operation of an optical indicator is as follows. The electric field distribution over an insulation structure changes with breakage of the integrity of its separate parts; when the potential difference at a damaged section decreases, the voltage at the undamaged part correspondingly increases. A faulty condition of the insulating structure can be determined using the light intensity of an indicator installed in the section of the insulating structure or pylon, since the luminance depends on the voltage drop across its terminals. Experiments showed that such insulation failure can visually be determined without using any additional devices, for example, during routine inspections. It is shown that it is possible to produce indicators that are easy to manufacture and do not require any additional maintenance.