The Experimental Study Of Ultraviolet Sensor To Detect Partial Discharges Of High Voltage Equipments

With voltage advance of electric equipment there are higher demand to the structure of insulation and the reliability of operation. Under the strong electric field, it's a popular problem that some weakness parts of insulation would discharge. There is abundant character information in partial discharge. It could be used to inspect the insulating situation of high voltage's equipment and avoid incident. At present, the problem of the on-line partial discharge monitoring system focus on how can we extract the signal of partial discharge under the strong Electro Magnetic Interference. Because the producing of UV light would go with discharge, so this paper adopts light sensor which insulate with primary circuit test the partial discharge under the strong Electro Magnetic Interference.In this paper, solar-blind ultraviolet detector which has a narrow spectral sensitivity and insensitive to visible light was chosen and used. Research methord and results are given as follows:â—‹1 First of all, through the test of pin-plate typical models corona, the driving voltage and test distance which is match for sensor can be find out. Through the experiment, we can find that the number of UV pulse can reflect the strength of discharge and discharge phase. Therefore, the author advances to put the frequency of UV pulse to be the characterizing parameter of partial discharge. And it'll be prepared for the further experiment.â—‹2 The second, using ultraviolet sensor, ultraviolet imaging device and high frequency electric sensor test the pin-plate typical models corona separately. And we analyze the result of the three methods.Test confirmed that UV photosensitive tube has the higher sensitivity compared with the current sensing device.â—‹3 The third, passing through a pretty of experiment, the number of UV pulse and the signal of partial discharge are improve that both of them could correspond with each other. So we would like to treat it as the characteristic quantity which can reflect the strength of partial discharge.â—‹4 The forth, the oil in the transformer attenuate the UV light. And light is easy to be total reflectance when it spread from the oil to the air. It's difficult to test the partial discharge in the oil of transformer. A small ultraviolet sensor was installed in the transformer's oil of, and tests the pin-plate typical models corona. Through experiment, we could check the signal of partial discharge in a certain distance.â—‹5 The fifth, base on the research which is mentioned above, the discharge of contaminated insulators were detected by ultraviolet sensor. Because of the infection of many conditions outside to the partial discharge of insulator, so it's difficult to estimate the contamination degree in the experiment by the frequency pulse ultraviolet. But distributing situation of pulse ultraviolet can reflect the status of discharge approximately.