Full
Outline
The flexible DC distribution network has characteristics such as a fast rising speed and a large amplitude of fault current. Therefore, the fast and reliable identification of DC line faults is a key technology that the DC distribution networks urgently need to break through. Aimed at the problems of poor selectivity of single-end protection and a slow speed of multi-end protection in the existing flexible DC power grids, a fault protection method for flexible DC power grid based on the Canberra distance is proposed. First, according to the difference in polarity of current differential between the two terminals under internal and external faults in the flexible DC power grid, the Canberra distance is introduced to calculate the polarity similarity of fault current differential sampled at both ends of the line, so as to perform diagnosis of the fault area. Second, based on the fault characteristics of fault and non-fault lines at the time of fault occurrence, a ratio is formulated using the numerical difference in current differential between the two poles, thus selecting the fault pole. Finally, different fault scenarios are set to verify the applicability of the proposed method under different working conditions. Simulation results show that the proposed protection scheme can achieve correct fault location and pole selection under the conditions of different fault locations, different values of current-limiting reactance and different transition resistances.
36
7
| 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 |
关闭全屏
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62662699(Operation and Technical Support)
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
