基于LCC和混合型MMC的混合直流输电系统控制策略  

Control Strategy for Hybrid HVDC Transmission System Based on LCC and Hybrid MMC

作　　者：徐雨哲 徐政[1] 张哲任[1] 肖亮[1] 陆翌 李继红 裘鹏 XU Yuzhe;XU Zheng;ZHANG Zheren;XIAO Liang;LU Yi;LI Jihong;QIU Peng(Department of Electric Engineering,Zhejiang University,Hangzhou,Zhejiang 310027,China;State Grid Zhe jiang Electric Power Co.,Ltd.,Hangzhou,Zhejiang 310007,China)

机构地区：[1]浙江大学电气工程学院,浙江杭州310027 [2]国网浙江省电力有限公司,浙江杭州310007

出　　处：《广东电力》2018年第9期13-25,共13页Guangdong Electric Power

基　　金：国家电网公司科技项目(5211011600R4);国家863高技术基金项目(2011AA05A119)

摘　　要：混合直流输电系统应用于远距离大容量输电时,存在直流侧故障自清除问题和送端交流系统故障后的功率续传问题,这两个关键问题的一种解决方案是采用整流站使用电网换相换流器、逆变站使用混合型模块化多电平换流器(modular multilevel converter,MMC)的混合直流输电系统。为此首先分析混合型MMC的运行原理,及直流运行范围与子模块配比之间的关系;然后设计两种混合直流输电系统的控制策略,并介绍闭锁处理和无闭锁故障穿越两种可行的直流故障处理方法;最后在PSCAD/EMTDC中搭建双极混合直流输电系统,对比分析不同控制策略和直流故障处理方法的响应特性。仿真结果表明,所设计的混合直流输电系统控制策略能够有效地处理直流侧故障和送端交流系统故障。When the hybrid HVDC transmission system is used for long-distance and large capacity power transmission, there are problems of fault self-clearance at DC side and power-continuation after fault of sending-end AC system. One of solutions to these two key issues is to adopt a kind of hybrid HVDC transmission system using the line commutated converter （LCC） for the rectifier station and the modular multilevel converter （MMC） for the inverter station. Therefore, this paper firstly analyzes operating principle of the hybrid MMC and relationship between DC operating range and full-bridge submodule proportion. Then it designs two kinds of control strategies for the hybrid HVDC transmission system and introduces two feasible DC fault processing methods including blocking treatment and blocking-free fault ride-through. In PSCAD/ EMTDC, it builds a bipolar hybrid DC transmission system by simulation, compares and analyzes response characteristics of two different control strategies and DC fault processing methods. Simulation results indicate the designed control strategy for the hybrid HVDC transmission system could effectively deal with DC side faults and faults of sending-end AC system.

关 键 词：混合型模块化多电平换流器 混合直流输电 直流故障清除 子模块配比 降压运行 

分 类 号：TM721.1[电气工程—电力系统及自动化] TM76