摘要
换流阀是实现高压直流输电的核心设备,其在运行过程中承受来自内部和外部的各种过电压。通过提取换流阀内的寄生电容参数和寄生电感参数,建立了过电压作用下换流阀的宽频等效电路模型。在此基础上,计算了换流阀在各种过电压(操作、雷电、陡波过电压)作用下阀层的电压梯度以及阀组件的电压分布,并对其影响因素进行了分析,得到了换流阀在各种过电压作用下电压分布的一般规律。研究结果表明,换流阀系统的寄生电容参数能够影响过电压分布的电压梯度,而换流阀内各元件的参数能够影响晶闸管两端过电压的大小。最后提出了一些改善措施。
Converter valves are the kernel components in HVDC transmission system, which are exposed to various overvoltages from both internal and external system during operation. A wideband equivalent circuit for the whole valve tower was built upon the stray capacitances and inductance of the valves extracted with different methods. Based on this circuit model, the voltage gradient of valve layers and voltage distribution among valve components were calculated under different kinds of overvoltages including switching, lightening and fast front overvoltage, and the influence factors were also discussed. Some regularity was obtained, e.g. the stray capacitances of the valves have an effect on the overvoltage distribution among valve components, while the parameters of the valve components can influence the voltage drop on thyristors. Lastly, some improved measures are proposed.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2010年第22期120-126,共7页
Proceedings of the CSEE
基金
国家自然科学基金项目(50707008
50777017)
"十一五"国家科技支撑计划重大项目(2006BAA02A20)~~
关键词
高压直流输电
换流阀
宽频建模
寄生参数
过电压分布
HVDC transmission
converter valve
wideband modeling
stray parameter
overvoltage distribution
