锁相环对多端柔性直流稳定性作用分析及参数选择研究  

Influence of PLL on the Stability Analysis of VSC-MTDC and Parameter Selection

作　　者：熊凌飞 韩民晓[1] 姚蜀军[1] 

机构地区：[1]华北电力大学新能源电力系统国家重点实验室,北京102206

出　　处：《电工技术学报》2015年第16期203-212,共10页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(51177044);高等学校学科创新引智计划("111"计划)(B08013)资助项目

摘　　要：首先详细推导了多端柔性直流输电(VSC-MTDC)交/直流系统的小信号模型,包括换流器及其控制系统(测量环节、内环/外环、锁相环)、交流系统及直流线路等4部分。其次,基于PSCAD/EMTDC建立了相应的电磁暂态模型,并将二者在时域下进行了详细比对,验证了小信号模型的正确性。采用根轨迹方法定量分析了PLL,内环及外环等各部分控制系统参数对VSC-MTDC稳定性的影响,并指出PLL对其影响不能忽略,最后文中给出了各参数的稳定范围。Firstly, this paper presents the small signal model of VSC-MTDC, including converter, control system（measuring, inner loop/outer loop, PLL）, AC system and DC lines. Secondly, the model validation is achieved in time domain by the comparison with an electromagnetic transient state model which is built based on PSCAD/EMTDC. Then, the impact of parameters of PLL, inner loop and outer loop on the stability of VSC-MTDC is quantitatively analyzed based on root locus method, which indicates that PLL has a significant influence on the stability of VSC-MTDC and cannot be ignored. At last, the stability ranges of each parameter are defined.

关 键 词：多端柔性直流输电 锁相环 小信号 稳定性 根轨迹 

分 类 号：TM721.1[电气工程—电力系统及自动化]