小水电富集电网的柔性直流异步联网方案研究  

Study on VSC-HVDC Asynchronous Interconnection Schemes for Regional Grids With Concentrated Small Hydropower

作　　者：游广增[1] 徐政[2] 刘昇[2] 肖亮[2] 盛能进 

机构地区：[1]云南电网有限责任公司,云南省昆明市650011 [2]浙江大学电气工程学院,浙江省杭州市310027

出　　处：《电网技术》2016年第4期1059-1065,共7页Power System Technology

基　　金：国家863高技术基金项目(2012AA050205)~~

摘　　要：多特性小水电群大规模接入消纳是我国电网发展过程中亟待解决的问题。云南西部大规模小水电群集中送出地区存在弱阻尼区间振荡模式,是制约该地区电力送出的主要因素。为避免大规模小水电群引发全网的弱阻尼振荡,可通过柔性直流输电系统将小水电富集电网和主网进行异步联网,使参与因子最大的机群与主网机群形成电气隔离。以云南电网为背景,从经济性和降低直流系统故障概率的角度,设计了柔性直流背靠背异步联网方案;从优化小水电富集电网潮流分布的角度,设计了多端柔性直流异步联网方案。比较了2种方案对电网小扰动稳定性和小水电富集电网送出能力的提升效果。仿真结果表明:2种方案均可增强云南电网的小扰动稳定性,并有效提升小水电富集电网的送出能力。Large-scale integration and accommodation of multi-characteristic small hydropower is an urgent problem for power grids in China. A weak damping oscillation mode exists in western Yunnan power grid, where large-scale small hydropower is delivered in concentration. And this is the major constraint limiting transmission capacity of this area. To avoid weak damping oscillations of whole grid triggered by large-scale small hydropower, VSC-HVDC systems can be used to connect small hydropower concentrated grids to backbone grid asynchronously to electrically isolate machine groups with largest participation factor from machine groups in backbone grid. This paper designed a VSC-HVDC back-to-back asynchronous interconnection scheme for enhancing economy and reducing DC system fault probability. Besides, from perspective of optimizing power flow distribution of small hydropower concentrated grids, a VSC-MTDC asynchronous interconnection scheme was designed. Effects of the two schemes on system small-signal stability and transmission capacity of small-hydropower concentrated grids were compared. Simulation results showed that both schemes could enhance small-signal stability of Yunnan grid and increase transmission capacity of small hydropower concentrated grids effectively.

关 键 词：云南电网 小水电群 小扰动稳定性 柔性直流 异步联网 

分 类 号：TM72[电气工程—电力系统及自动化]