引用本文: | 周嘉阳,李凤婷,陈伟伟,等.基于电容放电特征的柔性直流配电网线路保护方案[J].电力系统保护与控制,2019,47(8):42-48.[点击复制] |
ZHOU Jiayang,LI Fengting,CHEN Weiwei,et al.Line protection schemes for flexible DC distribution network based on capacitor discharge[J].Power System Protection and Control,2019,47(8):42-48[点击复制] |
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摘要: |
针对换流设备直接接入直流母线的双端柔性直流配电网的保护配置问题,提出一种基于单端电气量的线路保护方案。首先分析了双端柔性直流配电网的直流线路故障特征,其次重点分析了处于不同母线处的换流器并联电容之间的放电特征差异。结合该差异设计出能够有效识别故障区域、在5 ms内隔离故障的主保护。同时为解决主保护可能存在检测失败的问题,设置了利用过电流判据以及动作延时的后备保护方案。最后通过PSCAD/EMTDC搭建仿真模型验证了所提方案的有效性。 |
关键词: 直流配电网 故障检测 并联电容 电容放电 电流微分 |
DOI:10.7667/PSPC180580 |
投稿时间:2018-05-16修订日期:2018-07-27 |
基金项目:新疆维吾尔自治区自然科学基金项目资助(2016D 01C036) |
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Line protection schemes for flexible DC distribution network based on capacitor discharge |
ZHOU Jiayang,LI Fengting,CHEN Weiwei,DA Tana,LIANG Luming |
(College of Electrical Engineering, Xinjiang University, Urumqi 830047, China;Economics and Technology Research Institute, State Grid Xinjiang Electric Power Company, Urumqi 830047, China;Urumuqi Power Supply Company, State Grid Xinjiang Electric Power Company, Urumuqi 830047, China) |
Abstract: |
In order to solve the protection configuration problem of two-terminal flexible DC distribution network when the converters access to DC buses directly, this paper presents a new protection scheme based on single-end electrical signals. Firstly, the fault characteristics of the two-terminal flexible DC distribution network are analyzed, and the difference of discharge characteristics of converts’ shunt capacitor at different busbars are analyzed especially. A main protection is designed based on the differences, which can identify fault areas effectively and isolate the fault within 5 ms. In order to solve the issue of failure detection of main protection, the backup protection is designed based on overcurrent criterion and action delay. Finally, a PSCAD/EMTDC simulation model is built and the simulation results show that the schemes are effective. This work is supported by Natural Science Foundation of Xinjiang Uygur Autonomous Region (No. 2016D01C036). |
Key words: DC distribution network fault detection shunt capacitor capacitor discharging current derivative |