The insulating properties of the doubly-fed motor stator coil after different cycles of cold and heat circulation was compared and its service life was assessed under different high frequency voltage to study the cold and hot shock resistance and high-frequency pulse electrical ageing performance of the doubly-fed generator stator coil. The results show that the cold and heat circulation has little effect on the insulating properties of doubly-fed generator stator coil. With the increase of high frequency ageing time, both the dielectric loss factor and its increment increase, and the insulation resistance increases at first and then decreases. The partial discharge inception voltage of the coil after high frequency pulse is smaller than that of the unaged coil, and the high-frequency pulse electrical ageing life of the stator coil is calculated to be more than 30 years.
| 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 |