In this paper, the physicochemical and electrical properties of oil-paper insulation in the process of surface discharge deterioration under static and flowing oil conditions were studied. The discharge product and moisture of oil-paper insulation were analyzed by infrared spectrometer and micro-water measuring instrument. The multilayer microstructure of oil-paper insulation was analyzed by viscosity tester, X-ray diffractometer, and scanning electron microscope. The conductivity, electric strength, and partial discharge of oil-paper insulation were analyzed by electrical measurement. The multi-type discharge deterioration characteristics of oil-paper insulation in static and flowing oil were compared and analyzed. The results show that the flow of oil slows down the surface discharge deterioration of oil-paper insulation, retards the rise of electrical conductivity and the decline of electric strength, and inhibits the occurrence and development of surface discharge. The surface conductivity determines the difficulty of surface discharge, and its increase results in the statistical distribution of surface discharge times showing a repetitive characteristic of "wave" gradually. Discharge frequency determines the surface discharge deterioration and destruction degree of oil-paper insulation, which is an efficient characteristic quantity to evaluate the deterioration state of oil-paper surface discharge.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |