VSC-HVDC系统宽频振荡z域阻抗判据研究  

Research on a z-domain impedance criterion for wideband oscillation of the VSC-HVDC transmission system

作　　者：张怡静 丁浩寅 时艳强 黄志光 钟伟伦 徐波 ZHANG Yijing;DING Haoyin;SHI Yanqiang;HUANG Zhiguang;ZHONG Weiun;XU Bo(East China Branch of State Grid Corporation of China,Shanghai 200120,China;College of Electrical Engineering,Shanghai University of Electric Power,Shanghai 200090,China)

机构地区：[1]国家电网有限公司华东分部,上海200120 [2]上海电力大学电气工程学院,上海200090

出　　处：《浙江电力》2024年第7期103-110,共8页Zhejiang Electric Power

基　　金：国家电网有限公司华东分部科技项目(52080023002J)。

摘　　要：为了深入分析VSC-HVDC(基于电压源换流器的高压直流输电)系统宽频振荡失稳的机理并快速准确评估系统的稳定性,提出一种基于z域阻抗的建模方法和稳定性判据。首先,基于精确离散化的方法,分别建立了考虑锁相环、电流内环和电压前馈控制的电压源型变流器z域阻抗模型,以及交流电网在全局坐标系下的z域阻抗模型。然后,基于盖尔圆定理提出广义禁区判据,分析了锁相环和线路阻抗对系统稳定性的影响。最后,搭建VSC-HVDC仿真系统进行分析,证明了所提广义阻抗判据的有效性。To delve into the mechanism behind wideband oscillation instability in voltage source converter based high voltage direct current(VSC-HVDC)transmission system and swiftly assess system stability with precision,a modeling method and a stability criterion based on z-domain impedance are proposed.Firstly,employing precise dis⁃cretization techniques,a z-domain impedance model is established for voltage-source converters considering phaselocked loops(PLLs),inner-current loop,and voltage feedforward control,along with a z-domain impedance model for AC grids in a global coordinate system.Subsequently,a criterion for generalized forbidden zone is proposed us⁃ing Gershgorin circle theorem to analyze the impact of phase-locked loops and line impedances on system stability.Finally,simulation analysis is conducted on the VSC-HVDC system to demonstrate the effectiveness of the proposed generalized impedance criterion.

关 键 词：宽频振荡 VSC-HVDC 稳定性分析 阻抗模型 离散化 

分 类 号：TM721.1[电气工程—电力系统及自动化] TM712