混合多端直流输电系统的小干扰建模方法  

Small-signal Modeling Method of Hybrid Multi-terminal HVDC System

作　　者：郑安然[1] 郭春义[1] 殷子寒 赵成勇[1] ZHENG Anran;GUO Chunyi;YIN Zihan;ZHAO Chengyong(State Key Laboratory for Alternate Electrical Power System With Renewable Energy Sources(North China Electric Power University),Changping District,Beijing 102206,China)

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学)

出　　处：《电网技术》2019年第11期4087-4096,共10页Power System Technology

基　　金：国家自然科学基金资助项目(51877077)~~

摘　　要：针对整流站采用电网换相型换流器(linecommutated converter,LCC)、逆变站采用模块化多电平换流器(modular multilevel converter,MMC)的混合多端直流输电系统(hybrid multi-terminalHVDC,H-MTDC),提出了一种通用的小信号建模方法。该建模过程将混合多端直流输电系统分为直流线路、LCC子系统和MMC子系统3大部分,各部分独立建模后通过连接变量连接在一起从而构成系统完整的小信号模型。然后,根据所提出的建模方法为一个混合三端直流输电系统建立了小信号模型,通过对比小信号模型在MATLAB中的仿真结果与PSCAD/EMTDC中系统的电磁暂态模型的仿真结果,验证了小信号建模方法的正确性。最后,采用特征根分析法,研究了三站的控制系统参数对混合三端直流输电系统小干扰稳定性的影响。该建模方法可以为混合多端直流输电系统小信号模型的建立以及后续的分析提供有价值的指导。A general small-signal modeling method was proposed for hybrid multi-terminal HVDC system(H-MTDC) using line commutated converter(LCC) for rectifier station and modular multilevel converter(MMC) for inverter station respectively. The modeling process divided the H-MTDC system into three parts: DC line, LCC subsystems and MMC subsystems. These parts were independently modeled and connected with connection variables to form a complete small signal model of the system. Then, based on the proposed modeling method, a small-signal model was established for a hybrid three-terminal HVDC transmission system. Correctness of the small-signal modeling method was verified by comparing the simulation results of the small-signal model in MATLAB with the simulation results of the electromagnetic transient model in PSCAD/EMTDC. Finally, by using eigenvalue analysis method, the influence of the control system parameters of three converter stations on the small disturbance stability of hybrid three-terminal HVDC system was studied. The modeling method provides valuable guidance for establishment of small-signal models of H-MTDC systems and subsequent analysis.

关 键 词：混合多端直流输电系统 小干扰模型 电网换相型换流器 模块化多电平换流器 

分 类 号：TM721[电气工程—电力系统及自动化]