特高压多端直流混合型MMC启动回路电阻和充电策略研究  

Research on starting loop resistance and charging strategy of UHV multiterminal DC hybrid MMC

作　　者：徐攀腾[1] 喻文翔 朱博 宋述波[1] 周登波[1] 樊友平[2] XU Panteng;YU Wenxiang;ZHU Bo;SONG Shubo;ZHOU Dengbo;FAN Youping(Guangzhou Bureau of Extra-High Voltage Transmission Company,China Southern Power Grid Co.,Ltd.,Guangzhou 510500,China;School of Electrical and Automation,Wuhan University,Wuhan 430072,China)

机构地区：[1]中国南方电网有限责任公司超高压输电公司广州局,广东广州510500 [2]武汉大学电气与自动化学院,湖北武汉430072

出　　处：《武汉大学学报（工学版）》2023年第7期851-858,共8页Engineering Journal of Wuhan University

基　　金：国家重点研发计划项目(编号:2016YFB0900903)。

摘　　要：混合型模块化多电平换流器(modular multilevel converter,MMC)在预充电阶段存在电容欠电压且电压不均衡现象,需要加装启动回路降低交流侧断路器合闸时产生的冲击电流及电压。分析了混合子模块拓扑下的MMC不控整流启动特性,介绍了混合型MMC的后续启动控制策略,并提出混合型MMC在不控整流阶段的最大充电电流峰值计算模型。分析了乌东德特高压混合三端直流工程柔直受端的启动策略,并根据不控整流启动期间启动回路的电气量特征,提出了启动电阻阻值及能量等技术要求,通过PSCAD/EMTDC仿真验证了所提启动策略和启动电阻设计的有效性。研究结论已被乌东德直流示范工程采用,该方法思路可适用于其他项目工程。In the pre-charging stage,there is capacitor undervoltage and voltage imbalance for hybrid modular multilevel converter(MMC).It is necessary to install a startup circuit to reduce the inrush current and voltage generated when the alternating current(AC)side circuit breaker is closed.The start-up characteristics of MMC uncontrolled rectification under the hybrid sub-module topology are analyzed,the follow-up start-up control strategy of hybrid MMC is introduced,and the maximum charging current peak value calculation model of hybrid MMC in uncontrolled rectification stage is proposed.The starting strategy of the flexible receiving end of Wudongde Ultra High Voltage(UHV)Hybrid Three-Terminal Direct Current(DC)Project is analyzed.According to the electrical characteristics of the starting circuit during uncontrolled rectification start-up,the technical requirements such as starting resistance value and energy are proposed,and the effectiveness of the proposed starting strategy and starting resistance design is verified by PSCAD/EMTDC simulation.The research conclusion has been adopted by the Wudongde DC demonstration project,and the method can be applied to other projects.

关 键 词：混合型MMC 充电特性 启动控制策略 启动电阻 乌东德特高压三端直流 

分 类 号：TM723[电气工程—电力系统及自动化]