基于谐波状态空间的高压直流输电系统SISO阻抗建模及稳定性分析  

SISO Impedance Modeling and Stability Analysis of HVDC System Based on Harmonic State Space

作　　者：王杨 夏菲 田旭 肖先勇[1] 徐群伟 马智泉 WANG Yang;XIA Fei;TIAN Xu;XIAO Xianyong;XU Qunwei;MA Zhiquan(College of Electrical Engineering,Sichuan University,Chengdu 610065,Sichuan Province,China;Electric Power Research Institute of State Grid Zhejiang Electric Power Co.,Ltd.,Hangzhou 310014,Zhejiang Province,China)

机构地区：[1]四川大学电气工程学院,四川省成都市610065 [2]国网浙江省电力有限公司电力科学研究院,浙江省杭州市310014

出　　处：《中国电机工程学报》2024年第5期1985-1998,I0027,共15页Proceedings of the CSEE

基　　金：国家自然科学基金项目(52177104)。

摘　　要：近年来,电网换相换流器型高压直流输电(line commutated converter based on high voltage direct current,LCC-HVDC)系统的稳定性问题得到广泛关注,多位专家学者建议采用谐波状态空间(harmonic state space,HSS)等线性周期时变建模方法对其分析。然而,HSS不可避免地提高了建模的复杂度与维数,在面对大规模交直流系统时具有局限性。同时,LCC-HVDC包含多类型谐波耦合,各部分耦合对稳定性的影响大小尚未得到充分论证。为此,文中以HSS为底层理论建立LCC-HVDC的耦合阻抗矩阵,揭示高压直流输电系统内部的谐波耦合机理。进一步,通过多频电路等效思想,提出三相系统多维阻抗的降维方法,将耦合阻抗矩阵无损降维成单入单出阻抗,以此分析不同次数的谐波耦合对阻抗特性与稳定性的影响。结果表明,考虑到13次谐波截断可以有效提升高压直流输电系统阻抗模型精度,但对稳定性分析结果的影响小于忽略工况变化、简化逆变侧带来的误差。In recent years,the system stability problem from line commutated converter based on high voltage direct current(LCC-HVDC) has been widely concerned.Several experts and scholars have suggested using linear periodic time-varying modeling methods such as harmonic state space(HSS) to analyze it.However,HSS inevitably increases the complexity and dimension of modeling and has limitations in the face of large-scale AC/DC systems.At the same time,LCC-HVDC contains multiple types of harmonic coupling,and the influence of each part of coupling on the stability has not been fully demonstrated.In this paper,the LCC-HVDC coupling impedance matrix is established based on HSS theory,and the mechanism of harmonic coupling in HVDC transmission system is revealed.Furthermore,through the idea of multi-frequency circuit equivalence,a dimension reduction model of multi-dimensional impedance of three-phase system is proposed.The coupling impedance matrix is lossless dimension reduction into single-input single-output impedance(SISO),and the influence of different harmonic coupling times on impedance characteristics and stability is analyzed.The results show that considering the 13th harmonic truncation can effectively improve the accuracy of the impedance model of HVDC transmission system,but the impact on the stability analysis results is less than the error caused by ignoring the change of working condition and simplifying the inverter side.

关 键 词：电网换相换流器型高压直流输电 谐波状态空间 谐波耦合 单入单出阻抗 稳定性分析 

分 类 号：TM721[电气工程—电力系统及自动化]