In this paper, the aggregation morphology of copper products in transformer oil and its influence on the ageing performance of transformer oil were investigated. The aggregation morphology of copper products in oil were tested by molecular weight distribution test method, and the ageing properties of oil samples were also analyzed periodically. The results show that the distribution of copper products changes with the ageing time obviously. The proportion of ionic copper decreases gradually with the ageing time, while the proportion of colloidal and suspended copper exhibit a tendency of continuous accumulation. The acid value and dielectric loss factor of the transformer oil increase significantly with ageing time, while the breakdown voltage decreases continuously. The concentration of ionic, colloidal, and suspended copper are positively correlated with the acid value and dielectric loss factor, and negatively correlated with the breakdown voltage.
| 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 |