李传西,黄金海,田培涛,付艳,杨泽松.基于MMC的多端柔性直流线路超高速保护关键技术研究[J].电测与仪表,2020,57(2):57-61. LI Chuan-i,HUANG Jinhai,TIAN Peitao,FU Yan,YANG Zesong.Research on Key Technology of Ultra-high Speed Protection of Multi-terminal Flexible DC Line Based on MMC[J].Electrical Measurement & Instrumentation,2020,57(2):57-61.
基于MMC的多端柔性直流线路超高速保护关键技术研究
Research on Key Technology of Ultra-high Speed Protection of Multi-terminal Flexible DC Line Based on MMC
In order to meet the requirements of ultra-high-speed protection action of multi-terminal flexible DC grid transmission lines, based on the traditional DC engineering line protection, the protection configuration and action strategy of flexible DC line are introduced.According to the characteristics of fault traveling wave, a traveling wave protection method is proposed.The method extracts the specific frequency band characteristics of the fault wave by S-transformation, and identify the ground short circuit fault by changing the amplitude of the fault traveling wave at different times, thereby forming a criterion for the traveling wave protection exit.Finally, based on the actual engineering parameters, the multi-terminal flexible DC simulation model built by RTDS and the closed-loop system composed of control and protection system are tested.The test results show that the method is effective and reliable.