基于MMC的多端直流输电系统直流侧故障控制保护策略  

A Control and Protection Scheme of Multi-terminal DC Transmission System Based on MMC for DC Line Fault

作　　者：仉雪娜 赵成勇 庞辉 林畅 

机构地区：[1]新能源电力系统国家重点实验室,华北电力大学,北京市102206 [2]国网智能电网研究院,北京市102200

出　　处：《电力系统自动化》2013年第15期140-145,共6页Automation of Electric Power Systems

基　　金：国家自然科学基金资助项目(51177042)~~

摘　　要：基于模块化多电平换流器(MMC)的多端直流(MTDC)输电技术,兼具MMC技术和多端柔性直流输电技术的优势,具有广阔的应用前景。文中分析了MMC的拓扑结构和运行机理,设计了基于电压裕度的多点直流电压控制策略,并对控制器进行了设计。在此基础上,分析了直流侧单极接地故障、极间短路故障、断线故障对基于MMC的MTDC系统的影响,并进一步提出了相应的控制保护策略与保护时序。利用电磁暂态仿真软件PSCAD/EMTDC对以上几种直流侧故障及控制保护策略进行了仿真,结果表明所提出的控制保护策略能够实现系统故障后的快速恢复,有效提高多端系统的可靠性和可用率。Since the modular multilevel converter（MMC） based multi-terminal DC（MTDC） transmission system has the advantage of MMC technology combined with that of the voltage source converter（VSC） based MTDC transmission system（VSC-MTDC）,it will have broad application prospects.The topological structure and working principle of MMC are presented.A multi-point DC voltage control strategy based on the DC voltage margin method is then proposed and the controller is designed.Furthermore,the impact of different DC faults of the system is analyzed and the corresponding control and protection strategies are given.This approach can realize automatic switching between active power and DC voltage control modes,thus improving system stability.The DC faults include single-line to ground fault,line to line fault and line break fault.Finally,the feasibility and effectiveness of the proposed control strategies and the designed controller are verified by simulation.

关 键 词：多端直流输电 模块化多电平换流器 多点直流电压控制 直流线路故障 控制保护策略 

分 类 号：TM721.1[电气工程—电力系统及自动化]