Impact of Grid Topology on Pole-to-ground Fault Current in Bipolar DC Grids: Mechanism and Evaluation
The fault current level analysis is important for bipolar direct current (DC) grids, which determines the operation and protection requirements. The DC grid topology significantly impacts the current path and then the fault current level of the grid, which makes it possible to limit the fault curren...
| Main Authors: | , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
IEEE
2023-01-01
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| Series: | Journal of Modern Power Systems and Clean Energy |
| Subjects: | |
| Online Access: | https://ieeexplore.ieee.org/document/9673696/ |
| _version_ | 1797859090454544384 |
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| author | Yingmin Zhang Wenxin Zhang Qiao Peng Baohong Li Yan Tao Min Zhang Tianqi Liu Frede Blaabjerg |
| author_facet | Yingmin Zhang Wenxin Zhang Qiao Peng Baohong Li Yan Tao Min Zhang Tianqi Liu Frede Blaabjerg |
| author_sort | Yingmin Zhang |
| collection | DOAJ |
| description | The fault current level analysis is important for bipolar direct current (DC) grids, which determines the operation and protection requirements. The DC grid topology significantly impacts the current path and then the fault current level of the grid, which makes it possible to limit the fault current by optimizing the grid topology. However, the corresponding discussion in the literature is indigent. Aiming at this point, the impact of grid topology, i.e., the connecting scheme of converters, on the pole-to-ground fault current in bipolar DC grids, is investigated in this paper, and the ground-return-based and metallic-return-based grounding schemes are considered, respectively. Firstly, the decoupled equivalent model in frequency domain for fault current analysis is obtained. Then, the impacts of converters with different distances to the fault point on the fault current can be analyzed according to the high-frequency impedance characteristics. Based on the analysis results, a simplified fault current index (SFCI) is proposed to realize the fast evaluation of impact of grid topology on the fault current level. The SFCI is then applied to evaluate the relative fault current level. Finally, the simulation results validate the model, the analysis method, and the SFCI, which can effectively evaluate the relative fault current level in a direct and fast manner. |
| first_indexed | 2024-04-09T21:23:51Z |
| format | Article |
| id | doaj.art-777ec2987a824821b64fd127a16c443d |
| institution | Directory Open Access Journal |
| issn | 2196-5420 |
| language | English |
| last_indexed | 2024-04-09T21:23:51Z |
| publishDate | 2023-01-01 |
| publisher | IEEE |
| record_format | Article |
| series | Journal of Modern Power Systems and Clean Energy |
| spelling | doaj.art-777ec2987a824821b64fd127a16c443d2023-03-27T23:00:51ZengIEEEJournal of Modern Power Systems and Clean Energy2196-54202023-01-0111243444510.35833/MPCE.2021.0003999673696Impact of Grid Topology on Pole-to-ground Fault Current in Bipolar DC Grids: Mechanism and EvaluationYingmin Zhang0Wenxin Zhang1Qiao Peng2Baohong Li3Yan Tao4Min Zhang5Tianqi Liu6Frede Blaabjerg7College of Electrical Engineering, Sichuan University,Chengdu,China,610065College of Electrical Engineering, Sichuan University,Chengdu,China,610065College of Electrical Engineering, Sichuan University,Chengdu,China,610065College of Electrical Engineering, Sichuan University,Chengdu,China,610065College of Electrical Engineering, Sichuan University,Chengdu,China,610065Electric Power Research Institute, State Grid Shanxi Electric Power Company,Taiyuan,China,030001College of Electrical Engineering, Sichuan University,Chengdu,China,610065AAU Energy, Aalborg University,Aalborg,Denmark,9920The fault current level analysis is important for bipolar direct current (DC) grids, which determines the operation and protection requirements. The DC grid topology significantly impacts the current path and then the fault current level of the grid, which makes it possible to limit the fault current by optimizing the grid topology. However, the corresponding discussion in the literature is indigent. Aiming at this point, the impact of grid topology, i.e., the connecting scheme of converters, on the pole-to-ground fault current in bipolar DC grids, is investigated in this paper, and the ground-return-based and metallic-return-based grounding schemes are considered, respectively. Firstly, the decoupled equivalent model in frequency domain for fault current analysis is obtained. Then, the impacts of converters with different distances to the fault point on the fault current can be analyzed according to the high-frequency impedance characteristics. Based on the analysis results, a simplified fault current index (SFCI) is proposed to realize the fast evaluation of impact of grid topology on the fault current level. The SFCI is then applied to evaluate the relative fault current level. Finally, the simulation results validate the model, the analysis method, and the SFCI, which can effectively evaluate the relative fault current level in a direct and fast manner.https://ieeexplore.ieee.org/document/9673696/Bipolar DC gridpole-to-ground faultgrid topologyfault current evaluationsimplified fault current index |
| spellingShingle | Yingmin Zhang Wenxin Zhang Qiao Peng Baohong Li Yan Tao Min Zhang Tianqi Liu Frede Blaabjerg Impact of Grid Topology on Pole-to-ground Fault Current in Bipolar DC Grids: Mechanism and Evaluation Journal of Modern Power Systems and Clean Energy Bipolar DC grid pole-to-ground fault grid topology fault current evaluation simplified fault current index |
| title | Impact of Grid Topology on Pole-to-ground Fault Current in Bipolar DC Grids: Mechanism and Evaluation |
| title_full | Impact of Grid Topology on Pole-to-ground Fault Current in Bipolar DC Grids: Mechanism and Evaluation |
| title_fullStr | Impact of Grid Topology on Pole-to-ground Fault Current in Bipolar DC Grids: Mechanism and Evaluation |
| title_full_unstemmed | Impact of Grid Topology on Pole-to-ground Fault Current in Bipolar DC Grids: Mechanism and Evaluation |
| title_short | Impact of Grid Topology on Pole-to-ground Fault Current in Bipolar DC Grids: Mechanism and Evaluation |
| title_sort | impact of grid topology on pole to ground fault current in bipolar dc grids mechanism and evaluation |
| topic | Bipolar DC grid pole-to-ground fault grid topology fault current evaluation simplified fault current index |
| url | https://ieeexplore.ieee.org/document/9673696/ |
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