特高压直流输电系统接地极引线双端不平衡保护

摘要

在目前工程中现有的接地极线不平衡保护和接地极线差动保护原理基础上分析并提出接地极引线双端不平衡保护.所提的双端不平衡保护原理,具有保护线路全长,识别引线断线和金属接地故障并能够计算出故障位置,不受过渡电阻的影响,以及定值整定简单等优点.采用EMTDC/PSCAD仿真验证了理论分析的正确性,最后采用实时数字仿真器(RTDS)仿真验证了所提保护动作策略的可行性.%First of all,an analysis is made of the principle of unbalance and differential protection of electrode line prior to proposing the paper.The double end unbalance protection can protect the full length of the electrode line,distinguish between the open circuit and grounding fault,and calculate the fault distance,which is not affected by transition resistance,and the principle of setting values is simple.The EMTDC/PSCAD simulation software is adopted to verify the correctness of theoretical analysis.Finally,real-time digital simulator is used to verify the feasibility of the proposed protection action strategies.