摘要
柔性直流输电系统用于多端输电方式时,其启动过程中各站间配合是系统稳定并快速达到运行状态的关键。针对三端模块化多电平(modular multilevel converter,MMC)柔性直流输电系统正常启动,设计了"一拖二拟合启动"的方式,即由一个逆变站带两个整流站启动,启动过程中适时切换控制方式,以获得平稳的启动过程。在PSCAD/EMTDC中建立了仿真模型,验证了该启动方式的可行性。此外,对多端直流启动的特殊工况进行了初步探索。
As the voltage-source converter high voltage direct current（ HVDC） transmission is for multi-terminal transmission,the coordination of each terminal is important to keep the system stable. In this paper,a novel method of single terminal energizing with fitting congtrol to start the modular multilevel converter（ MMC） is proposed for a three-terminal MMC-HVDC system with 2 rectifiers and 1 inverter. The inverter side AC system is used to charge the inverter and other 2 rectifiers. During the start process,the controllers are properly enabled to obtain smooth start process. A three terminal simulation system is built in PSCAD /EMTDC to verify the feasibility of the proposed method. Simulating results show that the proposed method is effective. In addition,the start process of multi-terminal MMC systems under some special operation conditions is also discussed.
出处
《南方电网技术》
2014年第4期47-51,共5页
Southern Power System Technology
