Control and DC fault isolation of DC/DC autotransformer

被引：0
作者：
Zuo W. [1 ]
Lin W. [1 ]
Yao L. [2 ]
Wen J. [1 ]
机构：
[1] State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan, 430074, Hubei
[2] China Electric Power Research Institute, Haidian District, Beijing
来源：
Wen, Jinyu (jinyu.wen@hust.edu.cn) | 1600年 / Chinese Society for Electrical Engineering卷 / 36期
基金：
中国国家自然科学基金;
关键词：
Auto transformer; DC auto transformer; DC grid; DC transmission; DC/DC converter;
D O I：
10.13334/j.0258-8013.pcsee.2016.09.011
中图分类号：
学科分类号：
摘要：
Dynamics of the internal AC circuit of DC/DC autotransformer (DC AUTO) was derived, then the controller for DC AUTO was proposed. DC fault response during high voltage side DC fault and low voltage side DC fault was analyzed. A method of replacing part of the submodules in MMC1 and MMC3 with self-blocking submodule was proposed to isolate high voltage side DC fault, and a method of cascading additional half-bridge submodules at MMC1 and MMC3 was proposed to isolate low voltage side DC fault. The impact of dc fault isolating capability on converter cost of DC AUTO was analyzed. Technical feasibility of the proposed controller and DC fault isolation method were verified by simulations on a ± 320 kV/± 500 kV, 1 000 MW DC AUTO using PSCAD/ EMTDC. Results show that a DC AUTO with bidirectional DC fault isolating capability has all the functions as a conventional DC/AC/DC. For the simulated test DC AUTO, the DC/AC/DC technology requires total converter rating of 2000 MW while only 1020 MW is required in DC AUTO. Power loss ratio of DC/AC/DC at full power condition is about 1.8% while it is only 0.97% for DC AUTO. The DC AUTO is promising to replace conventional DC/AC/DC technology at low and medium DC voltage stepping ratio. © 2016 Chin. Soc. for Elec. Eng.
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页码：2398 / 2407
页数：9
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