To improve the oil-paper insulation performance in oil-immersed transformers, this paper utilized hexamethyldisilazane coupled with dielectric barrier discharge (DBD) plasma to modify cellulose insulation paper. The physical morphology and chemical composition of the surface and cross-section of the modified insulation paper were characterized, and the influence of the medium flow rate on the insulation paper properties and oil-paper insulation performance was investigated. The results show that at a medium flow rate of 15 mL/min, the oil-paper insulation performance is significantly enhanced. The dielectric constant of the modified insulation paper decreases to 2.5, the flashover voltage and electric strength increase by 33.8% and 25.0%, respectively, the water contact angle increases by 194.3%, and the water absorption decreases by 44.9%. Silicon-containing thin films are deposited on the surface of the insulation paper and penetrate into the interior of the fibers, which can introduce deep traps to restrict charge migration and fill the fiber pores with hydrophobic substances. The introduction of the low-polarity film reduces the dielectric constant of the insulation paper, mitigates the electric field distortion at the oil-paper interface, and improves the interfacial bonding ability of the oil-paper interface, thereby enhancing the oil-paper insulation performance.
| 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 |