| 引用本文: | 束洪春,任敏,单节杉,田鑫萃,薄志谦.换流站阀侧交流接地故障电流快速抑制方案[J].电力自动化设备,2022,42(6): |
| SHU Hongchun,REN Min,SHAN Jieshan,TIAN Xincui,BO Zhiqian.Fast suppression scheme of AC valve side grounding fault current in converter station[J].Electric Power Automation Equipment,2022,42(6): |
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| 摘要: |
| 换流站阀侧交流接地故障下，故障点通过接地极与下桥臂组成故障回路，其故障冲击电流大，不能通过断路器切除。分析表明，接地极在对称运行时基本没有电流流过，并在单极架空线路故障和换流站阀侧交流接地故障中提供了故障回路。因此，接地极引入故障限流装置不仅对系统的正常运行没有影响，且能有效抑制单极故障电流和阀侧交流接地故障电流，降低对直流线路保护及换流站保护的要求。分析了阀侧交流接地故障下的故障电流组成，从供电可靠性、故障限流效果等方面分析了故障限流器引入接地极所具有的优势，提出了故障限流器分散组合式安装方法，利用电容器组与故障限流电感的组合投入，实现对回路中能量的吸收和故障电流上升率及峰值抑制的新型故障限流器拓扑结构。利用PSCAD/EMTDC平台搭建了双端柔性直流输电系统，仿真结果验证了接地极安装位置的优越性，并证明了新型故障限流器的有效性。 |
| 关键词: 架空柔性直流电网 阀侧交流接地故障 故障电流特性 接地极 故障限流 |
| DOI：10.16081/j.epae.202203031 |
| 分类号:TM721.1 |
| 基金项目:国家自然科学基金资助项目(52167011,52037003)；云南省重大科技专项计划项目(202002AF080001) |
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| Fast suppression scheme of AC valve side grounding fault current in converter station |
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SHU Hongchun, REN Min, SHAN Jieshan, TIAN Xincui, BO Zhiqian
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Faculty of Electric Power Engineering, Kunming University of Science and Technology, Kunming 650051, China
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| Abstract: |
| Under the AC valve side grounding fault in the converter station, the fault point forms a fault circuit with the lower bridge arm through the grounding electrode. The fault impulse current is too large to be removed through the circuit breaker. The analysis shows that when the grounding electrode runs symmetrically there is basically no current flowing through it, and provide a fault circuit in the single-pole overhead line fault and the AC valve side grounding fault in the converter station. Therefore, introducing fault current limiting device into grounding electrode not only has no impact on the normal operation of the system, but also can effectively suppress the single-pole fault current and AC valve side grounding fault current, and reduce the requirements for DC line protection and converter station protection. The composition of fault current under AC valve side grounding fault is analyzed. The advantages of introducing current limi-ter into grounding electrode are analyzed from the aspects of power supply reliability and current limiting effect. A decentralized combined installation method of current limiter is proposed, which uses the combined input of capacitor bank and current limiting inductor to realize a novel topology of fault current limiter to absorb energy in the circuit and suppress the rise rate and peak value of fault current. A two terminal flexible DC transmission system is built on PSCAD/EMTDC platform. The simulative results verify the superiority of the installation position of grounding electrode and the effectiveness of the novel current limiter. |
| Key words: overhead flexible DC power grid AC valve side grounding fault fault current characteristics grounding electrode fault current limiting |
