Analysis Of Influencing Factors Of Corona Discharge Ultraviolet Detection And Research On Discharge Intensity Evaluation Method

With the rapid development of national economy,China’s demand for electric energy is increasing.Electrical equipment in the manufacturing,transportation,installation and operation may lead to its insulation performance reduction,which leads to the electrical equipment corona discharge phenomenon,threatening the normal operation of the power system.As a new insulation detection technology,ultraviolet detection technology is gradually widely used in the field of corona discharge detection.Regular ultraviolet detection of electrical equipment can grasp the insulation performance of the equipment in time and find the insulation defects existing in the equipment,so as to prevent accidents.Therefore,the research on UV detection technology has important practical significance.Firstly,this thesis studies the influence of detection distance,gain,humidity and other factors on the results of UV detection through experiments,and corrects the counting rate between three types of commonly used UV detector.Digital image processing technology is used to process the ultraviolet detection images of electrical equipment taken by the ultraviolet detector,and then the discharge area of the ultraviolet detection image is segmented and the discharge area is calculated.Finally,the correction formula of discharge area with detection distance and gain is fitted,and the method of classifying and evaluating discharge intensity of electrical equipment based on discharge area is proposed.Under the same discharge conditions,the number of photons decreases with the increase of detection distance,and the relationship between the two is roughly a power function with the power exponent ranging from-1.909 to-1.827,the photon number along with the increase of the gain showed a trend of decrease after the first increase,and humidity,detection Angle and wind speed have less effect on the uv test results,in the practical engineering detection can be ignored.Fuzzy c-means clustering algorithm can not change the discharge area size,location and shape of the implementation of the discharge area in the graph partition,filter ultraviolet detection image of the discharge device,scene background,information bar part of the instrument interface,mathematical morphology filtering can eliminate discrete discharge points around the discharge area,The contour of the discharge area in the image is also more continuous and smooth.On the basis of the above research,the discharge area was introduced to characterize the discharge intensity.The corona discharge intensity of electrical equipment was classified according to the section of the corona/arc discharge intensity in the guide"Guidelines for Application of Ultraviolet Diagnosing Technology for DL/T 345 Live Equipment".Proposed using the discharge area of different detection distance,the gain of the image in the electrical equipment discharge intensity assessment method,solves the cannot exist in the use of the photon number for detecting ultraviolet image of several discharge point discharge intensity assessment and does not test for different distance,under the gain of the discharge intensity of ultraviolet detection images of unified evaluation problem,At the same time,it provides the related theoretical standard and new evaluation method for the actual engineering testing and discharge evaluation of UV detection technology.