基于自适应虚拟阻抗的构网型与跟网型逆变器主导微网系统无功功率均分控制策略  

Reactive Power Sharing Control Strategy for Microgrids Dominated by Grid-Forming and Grid-Following Inverters Based on Adaptive Virtual Impedance

作　　者：邱晓燕[1] 闫幸 周毅[1] 林号缙 臧天磊 周步祥[1] QIU Xiaoyan;YAN Xing;ZHOU Yi;LIN Haojin;ZANG Tianlei;ZHOU Buxiang(College of Electrical Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学电气工程学院,成都市610065

出　　处：《电力建设》2024年第1期22-32,共11页Electric Power Construction

基　　金：国家自然科学基金项目(51907097,52307126);中央高校基本科研业务费专项资金资助项目(2022SCU12006)。

摘　　要：在由构网型(grid-forming,GFM)与跟网型(grid-following,GFL)逆变器主导的孤岛微网系统中,GFL逆变器主动参与功率的二次调节可增强微网系统的无功功率调节与带载能力。然而,由于逆变器容量不等、控制方式不同以及输电线路阻抗不匹配,实现异构逆变器间无功功率均分面临困难。文章将倒下垂控制应用于GFL逆变器使其具备类似GFM逆变器的功率下垂特性,并分析了GFM与GFL逆变器互联下无功功率的分配原理;在此基础上,提出一种通过相邻逆变器无功功率偏差信息驱动的自适应虚拟阻抗策略,实现GFM与GFL逆变器在不同输电线路阻抗、不同分配比例下的自适应无功功率均分,并给出相关控制参数的选取方法;最后,在MATLAB/Simulink中测试所提策略在线路阻抗变化、负荷投切、逆变器容量不等与即插即用场景下的适用性,验证了理论分析的正确性。In the island microgrid system dominated by grid-forming(GFM)and grid-following(GFL)inverters,the active participation of GFL inverter in the secondary reactive power sharing can make the reactive power regulation and load capacity performance of microgrid enhanced.However,reactive power sharing is difficult to be achieved between inverters because of the different capacities,control methods of inverters and the mismatched impedance of transmission lines.Therefore,the freq/watt and volt/var droop control is applied to GFL inverter to make its power characteristic similar as GFM inverter,and the principle of reactive power sharing between GFM and GFL inverters is analyzed.On this basis,an adaptive virtual impedance strategy driven by reactive power sharing deviation information of adjacent inverters is proposed,which can achieve the adaptive reactive power sharing of GFM and GFL inverters when transmission line impedance and inverter capacity are different,and the selection method of related control parameters is also given.Finally,the applicability of the proposed strategy under the cases of line impedance variation,load switching,inverter capacity inequality and plug-and-play are tested in MATLAB/Simulink,so the correctness of the theoretical analysis is verified.

关 键 词：孤岛微网系统 无功功率分配 自适应虚拟阻抗 构网型逆变器 跟网型逆变器 

分 类 号：TM732[电气工程—电力系统及自动化]