With the increasing connection of renewable energy power plants (REPPs), there are some problems that power frequency distance protection criterion cannot identify grid faults. Therefore, this paper focuses on the extraction algorithm of power frequency and protection criteria in the device, and analyzes the adaptability of distance protection algorithms from different manufacturers with high proportion of renewable energy power plants. Regarding the power frequency extraction algorithm, the aperiodic component characteristics of the shortcircuit current provided by different renewable energy power plants were explored. The error of Fourier algorithm caused by the influence of harmonic was further derived. For the protection criteria, the adaptability of directional circle, polygon, phase comparison, and power frequency variation distance protection was compared and analyzed, and the distance protection criteria that can be well applied to high proportion of renewable energy power plants were clarified.
| 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 |