虚拟同步电机控制下光伏微电网并入弱配电网的次同步振荡特性分析  

Sub-synchronous Oscillation Characteristic Analysis of VSG-based PV Microgrid Connected to a Weak Distribution Network

作　　者：姜新丽 JIANG Xinli(Xuchang KETOP Electrical Research Institute Co.,Ltd.,Xuchang 461111,China)

机构地区：[1]许昌开普电气研究院有限公司,河南许昌461111

出　　处：《电力学报》2024年第5期427-434,共8页Journal of Electric Power

摘　　要：为分析光伏微电网通过虚拟同步电机(virtual synchronous generator,VSG)控制接入弱配电网时的次同步振荡(sub-synchronous oscillation,SSO)特性,基于阻抗分析法展开了研究工作。首先,建立了VSG光伏微电网并入弱配电网的数学模型,解析了序阻抗特性;然后,通过正序阻抗幅频特性图探讨了系统参数改变对光伏微电网SSO的影响,利用MATLAB/Simulink对分析结果进行了仿真验证。研究结果表明,在弱电网环境下,VSG光伏微电网更易发生次同步振荡,且系统参数对振荡特性具有显著影响。此外,降低虚拟转动惯量,增加阻尼系数及一次调压系数,均能实现对光伏微电网次同步振荡的抑制,提高系统稳定性。该研究成果可为光伏微电网的稳定运行提供理论参考和实践依据。In order to analyze the sub-synchronous oscillation(SSO)characteristics of the PV microgrid connected to a weak distribution network through virtual synchronous generator(VSG)control,the research work based on the impedance analysis method is carried out.Firstly,the mathematical model of the VSG-based PV microgrid connected to the weak distribution network is established,and the sequential impedance characteristics are analyzed.Then,the influence of the system parameter changes on the SSO of the PV microgrid is explored using positive sequence impedance amplitude frequency characteristic diagram,and the analyzed results are verified by simulation using MATLAB/Simulink.The results show that the VSG-based PV microgrid is more prone to sub-synchronous oscillations under a weak grid environment,and the system parameters have a significant effect on the SSO.In addition,reducing the virtual moment of inertia,increasing the damping coefficient and the primary regulation coefficient can achieve the suppression of SSO of the VSG-based PV microgrid and improve the stability of the system.The research results can provide theoretical reference and practical basis for the stable operation of the PV microgrid.

关 键 词：光伏微电网 弱配电网 虚拟同步电机 次同步振荡 阻抗分析法 交越频率 

分 类 号：TM615[电气工程—电力系统及自动化] TM341