多端常规、混合直流交流故障响应特性对比研究  

AC Fault Response Characteristics Comparative Study on Multi-Terminal HVDC Transmission System

作　　者：苗璐 赵利刚 易杨 王彤 龙霏 姚文峰 MIAO Lu;ZHAO Ligang;YI Yang;WANG Tong;LONG Fei;YAO Wenfeng(Electric Power Dispatch and Control Center of Guangdong Power Grid Corporation, Guangzhou 510050,China;Electric Power Research Institute, CSG, Guangzhou 510663, China)

机构地区：[1]广东电网有限责任公司电力调度控制中心,广州510050 [2]南方电网科学研究院,广州510663

出　　处：《南方电网技术》2019年第5期1-7,共7页Southern Power System Technology

基　　金：广东电网公司规划专题项目资助(广东电网2019—2021年三年运行方式研究)~~

摘　　要：针对多端常规直流和不同混合方式的多端混合直流在交流系统故障情况下的不同响应特性,本文介绍了多端直流输电系统一次系统以及控制系统的机电暂态建模方法,以三端直流输电系统为例,构建一送端两受端的三端直流输电系统,考虑LCC-LCC-LCC、LCC-VSC-LCC、LCC-VSC-VSC 3种组合形式,建立了其对应的仿真模型,研究对比了不同的多端直流组合方式在不同电压跌落程度的交流系统故障情况下的响应特性。对比结果表明,在逆变侧采用VSC换流器可以有效的减少逆变侧因为交流系统故障发生换相失败导致直流系统不能进行有效的功率传输的情况;两个逆变站同时采用VSC换流器可以更大程度的发挥VSC换流器不会发生换相失败的优势,最大限度的保证直流功率的传输;同时,VSC换流器作用的充分发挥需要多端直流输电控制系统的紧密配合。Aiming at the different response characteristics of multi-terminal HVDC transmission system in the case of AC system faults, this paper introduces the electromechanical transient modeling method of the primary system and control system of multi-terminal HVDC transmission system. A three-terminal DC transmission system with one sending end and two receiving ends is constructed, considering the combination of LCC-LCC-LCC, LCC-VSC-LCC and LCC-VSC-VSC, the corresponding simulation models are established. This paper compares the response characteristics of different multi-terminal DC transmission system in the case of AC system faults with different voltage drops. The comparison results show that the VSC converter on the inverter side can effectively reduce the probability that the DC system cannot perform effective power transmission due to the commutation failure of inverter. The use of VSC converters in both inverters can give full play to the advantages of VSC converters without commutation failure, and maximize the transmission of DC power. At the same time, the full play of the VSC converter requires the close cooperation of the multi-terminal DC transmission control system.

关 键 词：多端直流 混合直流 故障响应 机电暂态 LCC换流器 VSC换流器 

分 类 号：TM721.1[电气工程—电力系统及自动化]