基于VSC与LCC混合的多点传输直流输电系统拓扑结构研究与特性分析  

Research on the Topology and Characteristic of Multi-terminal HVDC Based on VSC and LCC

作　　者：刘杉 余军[2] 贺之渊 刘泽洪[2] 郭贤珊[2] 林畅 刘杰[2] LIU Shan;YU Jun;HE Zhiyuan;LIU Zehong;GUO Xianshan;LIN Chang;LIU Jie(State Key Laboratory of Control and Simulation of Power System and Generation Equipment （Tsinghua University）, Haidian District, Beijing 100084, China;State Grid Corporation of China, Xicheng District, Beijing 100031, China;Global Energy Interconnection Research Institute, Changping District, Beijing 102211, China)

机构地区：[1]电力系统及发电设备控制和仿真国家重点实验室(清华大学),北京市海淀区100084 [2]国家电网公司,北京市西城区100031 [3]全球能源互联网研究院,北京市昌平区102211

出　　处：《中国电机工程学报》2018年第10期2980-2988,共9页Proceedings of the CSEE

摘　　要：该文提出一种充分利用相换相换流器（1ine commutation converter，LCC）和电压源换流器（voltage source converter，vsc）特点以及特高压输电线路和直流电缆优点的混合型直流输电系统。在资源丰富地区，采用LCC技术将汇集于当地交流电网的清洁电力转化为特高压直流电力，利用特高压直流架空线路造价经济、可靠、损耗低的特点，将电力输送到用能地区的边缘；采用LCC技术将部分电力转换为交流电力，注入当地电网；剩余电力通过直流电缆或架空线方式分散输送到受能地区的中心负荷区，以VSC方式注入当地交流电网。该文阐述该输电系统的拓扑结构，分析系统的应用场景，提出系统的控制策略。借助仿真手段，重点分析系统在启动、阶跃、LCC换相失败、VSC受端交流系统故障和直流架空线路故障等典型电磁暂态工况下的响应特性。研究表明，在各种暂态工况下，系统运行稳定，动态性能优越。This paper proposed a new hybrid DC transmission system which makes the maximum utilization of the line commutation converter （LCC） and voltage source converter （VSC）, as well as the overhead lines and DC cables. In resource-rich areas, the LCC can be employed to convert the clean energy into the UHVDC electrical power. By using the high voltage overhead line, which is cheap, reliable and low power losses, the electrical power can be transmitted to the edge of the load center by the LCC, and part of the electrical power can be fed to the local power system. The remaining electrical power will be separately delivered to the load center by the DC cables or overhead lines, converted by the VSC and injected to the local power system. In this paper, the hybrid DC system math model and control strategy were discussed. Based on the simulation analysis, the typical transit characteristic, such as the start, dynamic performance communication failure, line faults, and AC fault were presented. The results show that the system can keep stable and have superior dynamic performance in the various transits.

关 键 词：全球能源互联网 特高压直流输电 柔性直流输电 混合式多端直流 直流电缆 

分 类 号：TM85[电气工程—高电压与绝缘技术]