摘要
为较大程度提升现有交流线路的输电容量,以缓解输电网输电能力欠缺,潮流拥塞等问题,引入一种交流线路改造成直流线路的技术方案—三极直流。三极直流能够提高线路的传输容量,具有较高的内在冗余度和过负荷能力,并可充分借鉴已有工程的经验,应用前景值得期待。该文介绍了三极直流输电的基本运行原理,总结了其技术和应用上的特点和优势,同时根据不对称电流调节策略,从时序控制、极控制和接地极电流平衡控制3方面提出了三极直流输电特有的协调控制策略。仿真结果表明,所提出的协调控制策略能够使得转换期间直流系统功率传输保持稳定,接地极电流波动控制在较小范围内,有利于交直流系统长期稳定运行。
Promoting the transmission capacity of existing AC lines can mitigate the problems of transmission including capability shortage and power flow congestion, etc＇., so we introduced a technical method for converting AC lines into DC lines, namely the tri-pole HVDC. After using the method, a converted system will enhance transmission capacity, internal redundancy, and overload capacity. The application of the method can refer to a lot of experience from operating HVDC projects, and it has a promising future. Moreover, we introduced some basic operating mechanisms of tri-pole HVDC, and discussed the system＇s characteristics and advantages in both technology and applications. According to the asymmetric current regulation strategy, we put forward the peculiar coordinating control strategy for tri-pole HVDC from three as- pects, namely, the sequential control, the pole control, and the balanced current control on earth electrode. Simulation results show that, during transitions, the proposed coordinating control strategy can keep DC power transmission stable and limit the fluctuation of grounding current in a small range, which contributes to the long-term and stable operation of AC/DC systems.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2014年第2期620-628,共9页
High Voltage Engineering
基金
国家高技术研究发展计划(863计划)(2012AA050205)~~
关键词
三极直流输电
交流直流转换
电流调节策略
传输功率
换流站
协调控制
tripole HVDC
AC/DC conversion
current control strategy
transmission power
converter station
coordi-nation control
