In order to master the viscosity, thermal conductivity, electrical conductivity, and dielectric properties of transformer oil with different moisture content from normal temperature to extreme cold, we prepared four samples of 45# transformer oil with different moisture content, and tested their viscosity, thermal conductivity, electrical conductivity and dielectric properties from +30℃ to -50℃. The results show that with the decrease of temperature, the viscosity of transformer oil increases exponentially, the higher the moisture content, the higher the viscosity of transformer oil. The thermal conductivity is less affected by temperature and moisture content. The electrical conductivity and dielectric loss factor increase at first and then decrease with the decrease of temperature, the higher the moisture content, the higher the peak value of conductivity and dielectric loss factor, and the larger the corresponding peak temperature. While the relative dielectric constant increases approximately linearly with the decrease of temperature, the variation trend of relative dielectric constant of transformer oil with different moisture content is the same and the difference is small.
| 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 |