| 引用本文: | 李国庆,谭龙,王振浩,陈洪涛.单相接地故障对换流器内部环流影响的研究[J].电力系统保护与控制,2016,44(3):1-7.[点击复制] |
| LI Guoqing,TAN Long,WANG Zhenhao,CHEN Hongtao.Research of the influence on the circulation for AC system single-phase ground fault[J].Power System Protection and Control,2016,44(3):1-7[点击复制] |
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| 摘要: |
| 模块化多电平换流器直流输电系统(Modular Multilevel Converter HVDC, MMC-HVDC)由于各相上下桥臂电压之和彼此不一致，产生换流器内部环流。环流会造成换流器各相桥臂电流发生畸变，所以抑制环流尤为重要。通常的环流抑制方法是在系统正常的运行情况下对换流器内部环流进行抑制。首先分析了正常情况下的环流抑制方法，然后通过对交流系统单相接地故障进行分析。重点研究了故障条件下不平衡电流对内部环流及直流电流的影响，设计了附加控制器对故障条件下环流抑制策略进行改进。通过PSCAD/EMTDC仿真实验，验证了理论分析及改进措施的可行性。 |
| 关键词: 模块化多电平换流器直流输电系统 单相接地故障 内部环流 抑制方法 |
| DOI：10.7667/PSPC150554 |
| 投稿时间：2015-04-06修订日期：2015-09-02 |
| 基金项目:国家自然科学基金项目(51377016) |
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| Research of the influence on the circulation for AC system single-phase ground fault |
| LI Guoqing,TAN Long,WANG Zhenhao,CHEN Hongtao |
| (School of Electrical Engineering, Northeast Dianli University, Jilin 132012, China;Songyuan Power Supply Company, Songyuan 138000, China) |
| Abstract: |
| Because the upper and under bridge arm voltage of each phases are inconformity with each other based on MMC-HVDC, resulting in the internal circulation of converter. Circulation will cause each phase converter arm current distortion, so it is important to suppress the circulation. The usual method for inhibition circulation inhibits the internal circulation of converter under the normal operation condition. Firstly, it analyzes the method of inhibiting circulation under normal circumstances. Then, it focuses on the effects of unbalanced current under fault condition on the internal circulation and DC current through the AC system single-phase ground fault analysis and designs the additional controller to improve the traditional inhibition circulation strategy under fault conditions. Finally, it verifies the feasibility of theoretical analysis and improvement measures through the PSCAD/EMTDC simulation experiments. |
| Key words: modular multilevel converter HVDC (MMC-HVDC) single-phase ground fault internal circulation method of inhibiting |
