Transient Stability Analysis of Converter-based Islanded Microgrids Based on Iterative Equal Area Criterion Considering Reactive Power Loop Dynamics and Varying Damping  

作　　者：Xilin Li Jingyi Zhang Zhen Tian Xiaoming Zha Wei Wang Meng Huang Chong Shao 

机构地区：[1]Hubei Key Laboratory of Power Equipment&System Security for Integrated Energy,School of Electrical Engineering and Automation,Wuhan University,Wuhan,China [2]NARI Technology Co.,Ltd.,Nanjing,China [3]State Grid Gansu Electric Power Company,Lanzhou,China

出　　处：《Journal of Modern Power Systems and Clean Energy》2024年第4期1170-1182,共13页现代电力系统与清洁能源学报（英文）

基　　金：supported in part by the National Key Research and Development Program of China(No.2022YFB2402700);in part by the Science and Technology Project of State Grid Corporation of China(No.52272222001J).

摘　　要：With the rapid increase in the installed capacity of renewable energy in modern power systems,the stable operation of power systems with considerable power electronic equipment requires further investigation.In converter-based islanded microgrid(CIM)systems equipped with grid-following(GFL)and grid-forming(GFM)voltage-source converters(VSCs),it is challenging to maintain stability due to the mutual coupling effects between different VSCs and the loss of voltage and frequency support from the power system.In previous studies,quantitative transient stability analysis was primarily used to assess the active power loop of GFM-VSCs.However,frequency and voltage dynamics are found to be strongly coupled,which strongly affects the estimation result of stability boundary.In addition,the vary-ing damping terms have not been fully captured.To bridge these gaps,this paper investigates the transient stability of CIM consid-ering reactive power loop dynamics and varying damping.First,an accuracy-enhanced nonlinear model of the CIM is derived based on the effects of reactive power loop and post-disturbance frequency jump phenomena.Considering these effects will eliminates the risk of misjudgment.The reactive power loop dynamics make the model coefficients be no longer constant and thus vary with the power angle.To evaluate quantitatively the effects of re-active power loop and varying damping on the transient stability of CIM,an iterative criterion based on the equal area criterion theory is proposed.In addition,the effects of parameters on the stable boundary of power system are analyzed,and the dynamic interaction mechanisms are revealed.Simulation and experiment results verify the merits of the proposed method.

关 键 词：Transient stability CONVERTER iterative criterion reactive power loop post-disturbance frequency jump 

分 类 号：TM712[电气工程—电力系统及自动化]