基于电压源型换流器的多端直流配电系统降阶小信号模型  

Reduced-order Small Signal Model of Voltage Source Converter Based Multi-terminal Distribution Network

作　　者：李鲁阳[1,2] 裴玮 孔力[1,2] LI Luyang;PEI Wei;KONG Li(Institute of Electrical Engineering Chinese Academy of Sciences,Haidian District,Beijing 100190,China;University of Chinese Academy of Sciences,Shijingshan District,Beijing 100049,China)

机构地区：[1]中国科学院电工研究所,北京市海淀区100190 [2]中国科学院大学,北京市石景山区100049

出　　处：《电网技术》2019年第4期1187-1195,共9页Power System Technology

基　　金：国家科技部重点研发专项(2017YFB0903300);中科院前沿科学重点研究项目(QYZDB-SSW-JSC025)~~

摘　　要：含电压源型换流器(voltage source converter,VSC)的多端直流配电系统集成度高,电力电子装置数量较多,这导致系统小信号模型的阶数较高,从而增加了系统稳定性分析及全局控制器设计的难度。鉴于此,提出了一种新型的多端直流(multi terminal DC,MTDC)系统降阶小信号模型。首先,文章对VSC进行了参与因子分析,辨识了与直流电压主导运动模态呈高相关性的状态变量。以此为基础,基于瞬时功率理论推导出一种新型VSC降阶模型。基于该模型,文章建立了多端直流配电系统的降阶小信号模型。最后,文章将所建立的多端直流配电系统降阶模型与传统降阶模型及电磁暂态模型进行了对比分析。结果表明:相对于传统的降阶小信号模型而言,文中所提出的系统模型能够更精确地评估系统的稳定性。Voltage source converter(VSC) based multi-terminal DC(MTDC) power distribution system has high integration degree and a large number of power electronic devices. This makes order of system small signal model high,and increases difficulty of system stability analysis and global controller design. Aiming at these problems, a new reduced-order small signal model of MTDC system is proposed in this paper. Firstly, participation factor analysis of power electronic transformer is conducted, and the state variables highly correlated with DC voltage dominant mode are identified. On this basis, a new VSC reduced-order model is derived based on instantaneous power theory. Based on this model, a reduced-order small signal model of MTDC distribution system is established. Finally, comparison of the reduced-order model of MTDC power distribution system with traditional reduced-order model and electromagnetic transient model is conducted. Results show that the proposed reduced-order model can more accurately assess system stability.

关 键 词：电压源型换流器 多端直流配电系统 降阶小信号模型 稳定性 

分 类 号：TM721[电气工程—电力系统及自动化]