Long-term operation of distribution networks with persistent single-phase grounding faults will result in insulation deterioration and subsequent phase-to-phase short-circuit faults, and grounding arcs also pose potential fire risks. In order to improve the reliability of power supply and ensure the safety of equipment and environment, the active intervention arc suppression device can effectively reduce the current level of the fault point and extinguish the arc light generated by grounding by introducing the short-circuit current into the substation. However, most of the active intervention arc suppression devices use the zero-sequence voltage as the threshold as the starting criterion, and the resistance value of the single-phase grounding transition resistance has a great influence on the zero-sequence voltage. In order to ensure the efficient operation of the device, analyzes the functional relationship between the transition resistance and the zero-sequence voltage firstly, then deduces the calculation formula of the transition resistance by the vector triangle method and the functional relationship method, and explains the setting method of the zero-sequence starting voltage of the device, and finally verifies the validity and rationality of the calculation method of the endurance transition resistance and the parameter setting of the zero-sequence starting voltage through the simulation experiments and the high-impedance artificial single-phase grounding experiment.
| 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 |