基于半功率带宽法的改进模态分析法  

An improved modal analysis method based on half power bandwidth method

作　　者：王乐天[1] 薛嘉辰 张梦琪 赵斌[1] 刘振 李永刚[2] WANG Letian;XUE Jiachen;ZHANG Mengqi;ZHAO Bin;LIU Zhen;LI Yonggang(Power Grid Design and Research Institute,Shandong Electric Power Engineering Consulting Institute Co.,Ltd.,Jinan 250013,China;Department of Electrical Engineering,North China Electric Power University,Baoding 071003,China)

机构地区：[1]山东电力工程咨询院有限公司电网设计研究院,山东济南250013 [2]华北电力大学电力工程系,河北保定071003

出　　处：《电力科学与技术学报》2023年第5期129-142,共14页Journal of Electric Power Science And Technology

基　　金：山东电力工程咨询院股份有限公司研究项目(37-2021-34-K0012)。

摘　　要：现有模态分析法仅根据模态阻抗的幅值大小判断谐波谐振程度,可能导致错误的分析结论。针对此局限性,提出一种改进模态分析法,引入半功率带宽法对模态分析结果进行进一步求解和改进。首先,介绍模态分析法概念;然后,基于半功率带宽法对谐振进行分析,并提出改进模态分析法,引入性能指标对谐波谐振程度进行判定;接着,对多并网逆变器进行建模,构建系统节点导纳矩阵;最后,通过理论分析和仿真验证,在MATLAB/Simulink中搭建仿真系统,验证现有模态分析法的局限性和本文方法的有效性。结果表明,谐波谐振程度同时受到模态阻抗幅值和阻尼比的影响,通过提出的改进模态分析法可实现系统谐波谐振程度的评估。The existing modal analysis method only judges the harmonic resonance degree according to the amplitude of the modal impedance,which may lead to the wrong analysis conclusion.In view of this limitation,an improved modal analysis method is proposed in this paper,and the half-power bandwidth method is introduced to further solve and improve the modal analysis results.Firstly,the principle of modal analysis method is introduced.Secondly,the resonance analysis is carried out based on the half-power bandwidth method,and the improved modal analysis method is proposed to introduce the performance index to assist in determining the degree of harmonic resonance.Then,construct the multiple grid-connected inverter model and build the node conduction matrix.Finally,the modified modal analysis method is applied to the harmonic resonance analysis,and a simulation is built in MATLAB/Simulink to verify the limitations of the existing modal analysis method and the effectiveness of this method.The results show that the harmonic resonance degree is affected by both the amplitude of the modal impedance and the damping ratio.The improved modal analysis method can be used to evaluate the harmonic resonance degree.

关 键 词：模态分析法 半功率带宽法 谐波谐振 多并网逆变器 阻尼比 

分 类 号：TM464[电气工程—电器]