| The detection of ultra-violet (UV) light among discharge from high voltage (HV) apparatuses can be used to infer the insulation state of them, what's more, it also an effective way to check the faults of HV apparatuses. In this paper studies on the characteristics of UV light among apparatuses discharge and extraction of them are carried out, based on which detecting testers are developed, the main work and contributions are as follows:According to the gas discharge theory and characteristics of UV light among the discharge UV pulse method and UV power method are presented, which can detect the discharge from HV apparatuses, and comparison between them has been made. Based on above two methods, two different testers are developed with UV photo detector and UV photomultiplier tube respectively. An UV discharge tester with UV photomultiplier tube respectively adopts high speed amplify, high speed comparison and wave discrimination to get the UV pulse count. According to the characteristics of the UV pulse received by the tester, the UV pulse power is measured based on high speed digital integration technology, and relationship between the received UV pulse and output signal of the UV photomultiplier tube is derived, therefore the discharge power of the source can be obtained, which indicates the strength of apparatuses discharge. In addition, the whole process of apparatuses discharge can be reformulated by digital integration, which offer an easy way to analysis the discharge from HV apparatuses in detail.Discharge intensity variability theory is adopted to analyze the strength of apparatuses discharge, from which pulse variability and power variability are derived, at the same time analytical methods in time domain and frequency domain of variability are presented, analytical index in time domain measure of characteristics and AR power spectrum analytical method are applied on extracting the characteristics quantity of ultraviolet irradiation in apparatus discharge to resolve fault detection and analysis in practical apparatus.An UV electroscope for ultra-high-voltage (UHV) apparatuses and HV insulators tester are developed based on time domain analytical method. Tests to verify the electricity state of UHV transmission and apparatus were carried out with UV electroscope, and results indicate it's a strong tool to check the electricity state of UHV transmission and apparatus. HV insulators tester was used to detect faulty insulators in a series of HV tests, and conclusions have been drawn that when defective insulators come up in an insulators string, the relative discharge strength change, and the ratio exceeds 8%.In addition, tests on polluted insulators were carried out with the HV insulators tester, according the measured UV pulse from contaminated insulators, spectrum analysis of discharge variability is processed by adopting AR model method, power spectral composition, power spectral curve are analyzed and used to determine the contamination grade of insulators. Results indicate that when light contamination is applied to the surface of insulators, no primary spectrum peak rises, and frequency of primary spectrum peak decreases with the increasing of contamination degree,λof the power curve increases with the increasing of contamination degree, but K nearly keep the same value 1.8, relationship and characteristics can be used to infer the contamination degree of insulators.Method using the non-electrical quantity measuring tool(energy of light) to measure electric-field intensity is presented, light radiation field is adopt to express electric field, reaching the aim of measuring the electric field indirectly by light measuring. Finite element software MAXWELL 3D is adopted to proceed the electric field simulation of discharge model and electric field distribution of the discharge model is inverted into ultraviolet field distribution according the relation between electric field and discharge current. According the numerical relation between these two fields ultraviolet power measurement can be used to express the relative size of electric field which is measured at the higher position in electric field and the electric field can be measured indirectly by measuring the picket-age. At last data is analyses by field experiment, results show that: The values of UV flux density and electric field are maintain the same variation, data curve are very anastomosis; Correlation coefficient of the two value is between 5 and 9 , 81% of data have windage below 30% of reality value, and better Correlation On the whole,but there are a few deviations.Fuzzy set theory and ultraviolet measure is applied to detect the UV radiation. With the measured UV pulse, temperature, humidity of environment, the insulation state of insulators can be inferred. Tests at Bishan Tianjiawan transformer substation were carried out, the evaluation value of the objective insulators range from 0.1 to 0.2, which verifies the validity of the method.
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