| 引用本文: | 郑涛,国兴超,胡鑫,余越,郑现州,王兴国.逆变侧换流变压器故障性涌流产生机理及其对差动保护的影响[J].电力自动化设备,2019,39(9): |
| ZHENG Tao,GUO Xingchao,HU Xin,YU Yue,ZHENG Xianzhou,WANG Xingguo.Fault inrush current generation mechanism of inverter-side converter transformer and its influence on differential protection[J].Electric Power Automation Equipment,2019,39(9): |
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| 摘要: |
| 针对特高压直流系统逆变侧阀侧接地故障可能引发换流变压器故障性涌流的问题，讨论故障位于不同电压等级换流桥以及不同时刻下阀桥通断情况的差异，分析换相失败后阀侧故障电流特征，阐述逆变侧故障性涌流产生机理及其特征。在此基础上，分析计及故障性涌流影响的换流变差动保护动作特性。研究结果表明，故障性涌流可能导致换流变区外转区内故障时差动保护误闭锁，针对该问题，根据故障时阀侧电流直流分量发生极性反转的特点，提出一种新的防止差动保护误闭锁的解决方案。PSCAD/EMTDC仿真结果验证了理论分析的正确性。 |
| 关键词: 高压直流输电 换流变压器 差动保护 换相失败 故障性涌流 |
| DOI：10.16081/j.epae.201909015 |
| 分类号:TM77 |
| 基金项目:国家重点研发计划智能电网技术与装备重点专项资助项目(2016YFB0900600)；国家电网公司科技项目(多类型电力设备故障识别及保护技术研究)(5100-20195501-7A-0-0-00) |
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| Fault inrush current generation mechanism of inverter-side converter transformer and its influence on differential protection |
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ZHENG Tao1, GUO Xingchao1, HU Xin1, YU Yue2, ZHENG Xianzhou1, WANG Xingguo2
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1.State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing 102206, China;2.China Electric Power Research Institute, Beijing 100192, China
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| Abstract: |
| Since fault inrush current of converter transformer may be initiated by the grounding fault at valve side of inverter side of UHVDC system, the difference of valve bridge on-off condition with fault at converter bridge of different voltage levels and at different times is discussed, the fault current characteristics at valve side after commutation failure are analyzed, and the generation mechanism and characteristics of fault inrush current at inverter side are described. On this basis, the operation characteristics of conver-ter transformer differential protection considering the influence of fault inrush current are analyzed. Research results show that the fault inrush current may cause mal-block of differential protection at the transition of out-zone fault to in-zone fault of converter transformer, aiming at this problem, a novel solution scheme to prevent mal-block of differential protection is proposed according to the characteristics of polarity reversal of valve side DC component when fault occurs. Simulative results on PSCAD/EMTDC verify the correctness of theoretical analysis. |
| Key words: HVDC power transmission converter transformer differential protection commutation failure fault inrush current |
