Research On UV Imaging And Cooperative Detection Technology Of Power Equipment

The principle of ultraviolet(UV)imaging and infrared imaging is different,and each has its own indispensable advantages.Using alone UV or infrared imaging method to detect hidden trouble of power equipment will be insufficient,and it may lead to the timely detection of hidden trouble.UV and infrared imaging method are two complementary technologies.This paper analyzes the existing problems of ultraviolet image,and method for preprocessing them,and the relationship between UV image spot area and environmental factors such as voltage.And explores the difference and complementarity of the two imaging detection method.And finish the research by field test and laboratory simulation.The major work completed and results achieved is as follows.The paper proposes an adaptive image denoising algorithm based on the median,a algorithm of improving the image piexls based on contrast limited adaptive histogram equalization.The algorithms run fast,without manual adjustment parameters.After preprocessing,the UV image noise is small,which has a balanced brightness and clear edges.The paper proposes a segmentation method for the abnormal discharge area of UV image,based on the change of the adaptive histogram.The method can make accurate and complete segmentation of the abnormal discharge area,and achieve rapid detection and accurate positioning the discharge position of equipment.This paper is aimed at the FILIN UV imager made in Russia.The characteristics of power equipment is analyzed,whose UV image spot area change with the change of eight environmental factors,including voltage level,observation distance,instru-ment gain,temperature,humidity,air pressure,wind speed,pollution.The paper con-structes eight standard environmental factors,and sets up the corresponding rela-tionship between spot area and environmental factors,and fitted the correction factor,which help we compute the image spot area.The paper defines their relation formula between the partial discharge(PD)quantity and the UV image spot area,and the PD quantity is estimated by the spot area.The corresponding relationship between the PD quantity and the discharge fault level is defined.And the quantitative evaluation of the PD degree of the power equipment is realized.The difference and complementarity of UV and infrared imaging technology is discussed.The cooperative analysis function of infrared and UV is proposed.The paper normalizes the relative temperature difference between the abnormal heating areas of the infrared image.And normalizes the PD quantity of the abnormal discharge areas of the UV image.And combines the respective criteria of infrared and UV imaging to calculate the cooperative fault.The paper puts forward the standard of cooperative fault grade evaluation,and realizes the cooperative detection and analysis of infrared and UV imaging method.A fault diagnosis expert system based on the principle is designed.The system can intelligently complete the image preprocessing and cooperative analysis and fault level judgment,when the UV and infrared image input the system.