Impact of phase-locked loop on stability of active damped LCL-filter-based grid-connected inverters with capacitor voltage feedback

作     者：Xiaoqiang GUO Shichao LIU Xiaoyu WANG 

作者机构：Department of Electrical EngineeringYanshan UniversityQinhuangdaoChina School of MechanicalElectronicand Control EngineeringBeijing Jiaotong UniversityBeijingChina Department of ElectronicsCarleton UniversityOttawaON K1S 5B6Canada 

出 版 物：《Journal of Modern Power Systems and Clean Energy》 (现代电力系统与清洁能源学报（英文）)

年 卷 期：2017年第5卷第4期

页      面：574-583页

核心收录：

学科分类：0830[工学-环境科学与工程（可授工学、理学、农学学位）] 080801[工学-电机与电器] 0808[工学-电气工程] 08[工学] 0807[工学-动力工程及工程热物理] 

基　　金：supported by Science Foundation for Distinguished Young Scholars of Hebei Province(No.E2016203133) Hundred Excellent Innovation Talents Support Program of Hebei Province(No.SLRC2017059) 

主　　题：Phase-locked loop Small-signal stability Grid-connected inverter Active damping LCL filter Transfer function 

摘      要：Active damped LCL-filter-based inverters have been widely used for grid-connected distributed generation(DG) systems. In weak grids, however, the phase-locked loop(PLL) dynamics may detrimentally affect the stability of grid-connected inverters due to interaction between the PLL and the controller. In order to solve the problem, the impact of PLL dynamics on small-signal stability is investigated for the active damped LCL-filtered grid-connected inverters with capacitor voltage feedback. The system closed-loop transfer function is established based on the Norton equivalent model by taking the PLL dynamics into account. Using an established model, the system stability boundary is identified from the viewpoint of PLL bandwidth and current regulator gain. The accuracy of the ranges of stability for the PLL bandwidth and current regulator gain is verified by both simulation and experimental results.