Polluted Insulator Discharge Detection And Contamination Condition Evaluation Based On Ultraviolet Pulse Signal

Polluted ceramic insulator will discharge and radiate light signal under certain contamination and humidity, in the weak discharge stage, the light signal mainly distributed in ultraviolet (UV) waveband, so to detect the UV band signal can found early discharge phenomenon. In this paper a method based on the UV is used to detect the insulator surface discharge and to evaluate the contamination condition, and the main work is as follows.According to the air discharge theory and discharge spectra distribution character, the UV solar blind PMT is selected as the sensor and a discharge light pulse signal detection system is developed, the high voltage module voltage adjust and amplifier gain adjust is control by a single chip microcomputer, and the practical test showed that it has the character of good linearity and sensitivity and can measure the discharge effectively.Depend on the artificial climate chamber, By experiment, the UV pulse signal characteristics under different contamination degrees and humidity is studied. It is showed that with discharge stage development from corona discharge to arc discharge even breakdown, the UV signal amplitude is increased too. In this paper, two parameters of max pulse amplitude and the average pulse value in one minute is calculated and the relation curves of the above two parameters with the pollution degree and humidity.Based on the above experiment results, according to the fuzzy logic rules, using the fuzzy logic inference theory, a contamination condition evaluation model is established, and it can be used to evaluate the contamination condition effectively, and it has certain engineering practical application value to guide the insulator anti-fouling work in power system.