As a kind of environment friendly liquid dielectric with high ignition point and degradability, natural ester insulating oil is widely considered as a good substitute of mineral oil in power transformers. In order to improve the electrical and thermal ageing properties of natural ester-paper insulation system, the surface of cellulose insulation paper was modified by silane coupling agent, and the oil-paper composite insulation combinations of natural ester, traditional mineral oil, ordinary insulation paper, and silane modified insulation paper were conducted accelerated thermal ageing tests. The ageing characteristic paremeters of oil-paper during the thermal ageing of four combinations were compared and analyzed. The results show that the insulating paper modified by silane can maintain a relatively complete three-dimensional network structure of cellulose during thermal ageing, and improve the ageing resistance and electrical performance of the natural ester-paper system.
| 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 |