摘要
高压DC/DC变换器是构建直流电网的关键装备之一,其技术需求分析是其电气拓扑设计和系统应用研究的前提。文中着重围绕基于模块化多电平换流器的高压直流(MMC-HVDC)输电网用高压DC/DC变换器电气隔离功能的选择和故障隔离要求等问题展开探讨。从DC/DC变换器故障特性、系统绝缘造价和可靠性角度分析了不同接地方式的直流系统中DC/DC变换器的电气隔离需求,分析结果表明:对称单极系统中DC/DC变换器宜具备电气隔离功能,而双极系统宜采用非电气隔离拓扑。此外,从DC/DC变换器外部故障和内部故障两个角度对DC/DC变换器的故障隔离需求进行了研究。最后,通过仿真验证了隔离需求分析的正确性。
The DC/DC converter is one of the key devices of DC grid. The technological requirement analysis of the DC/I）C converter is the premise of its topology design and application research. The selection of electrical isolation function and the requirement of fault blocking of DC/DC converters for modular multilevel converter based high-voltage direct current （MMC HVDC） transmission systems are discussed. The electrical isolation requirements of DC/DC converter under different grounding systems are analyzed in terms of fault characteristics, insulation cost and system reliability. The analysis results show that electrical isolation is needed under symmetric monopole system and non-electrical isolation is better for bipolar system. Besides, DC/DC converter fault blocking demand is carefully investigated in terms of extermal and internal faults of the DC/DC converter. Finally, the analysis of electrical isolation and fault blocking demand of the DC/DC converter are verified through simulations.
作者
王新颖
汤广福
魏晓光
庞辉
WANG Xinying TANG Guangfu WEI Xiaoguang PANG Hui(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources （North China Electric Power University）, Beijing 102206, China Beijing Key Laboratory of High Power Electronics （Global Energy Interconnection Research Institute）, Belling 102211, China)
出处
《电力系统自动化》
EI
CSCD
北大核心
2017年第8期172-178,共7页
Automation of Electric Power Systems
