Science China Technological Sciences

, Volume 61, Issue 12, pp 1935–1949 | Cite as

The design and fault ride through control of un-interrupted DC-DC Autotransformer

  • MengBo Li
  • Wang XiangEmail author
  • WenPing Zuo
  • LiangZhong Yao
  • WeiXing Lin
  • JinYu Wen


This paper proposed a novel type of DC-DC converter, termed as un-interrupted DC Autotransformer (un-interrupted DC AUTO), which has the capability to ride through DC fault on either side of the converter without blocking any devices. Besides that, the adequately designed converter retains the advantages of DC AUTO technology, namely reduced investment cost and transmission loss. To begin with, the topology and basic attributes of the un-interrupted DC AUTO are illustrated. Then the design goals and the corresponding design procedures are analyzed. Furthermore, an effective control system is proposed to enable the converter steady operation during both normal and faulted conditions. Finally, a 1000 MW ±320 kV/±640 kV test system is built on PSCAD/EMTDC platform to verify the technical feasibility of the proposed converter and the effectiveness of the control strategy.


DC-DC power conversion DC Autotransformer HVDC converters DC fault control strategy 


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Copyright information

© Science in China Press and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • MengBo Li
    • 1
  • Wang Xiang
    • 1
    Email author
  • WenPing Zuo
    • 1
  • LiangZhong Yao
    • 2
  • WeiXing Lin
    • 1
    • 3
  • JinYu Wen
    • 1
  1. 1.State Key Laboratory of Advanced Electromagnetic Engineering and TechnologyHuazhong University of Science and TechnologyWuhanChina
  2. 2.Renewable Energy DepartmentChina Electric Power Research InstituteBeijingChina
  3. 3.TBEA China Xinjiang Sunoasis Co., LtdUrumqiChina

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