Transient Stability Analysis and Improved Control Strategy of PMSG-based Grid-forming Wind Energy Conversion System Under Symmetrical Grid Fault  

作　　者：Hai Xie Jun Yao Wenwen He Dong Yang Sheng Gong Linsheng Zhao 

机构地区：[1]State Key Laboratory of Power Transmission Equipment Technology,School of Electrical Engineering,Chongqing University,Chongqing 400044,China

出　　处：《Journal of Modern Power Systems and Clean Energy》2025年第1期128-141,共14页现代电力系统与清洁能源学报(英文)

基　　金：supported by the National Natural Science Foundation of China(No.51977019)。

摘　　要：The transient synchronization characteristics and instability mechanism of the permanent magnet synchronous generator(PMSG)-based grid-forming wind energy conversion system(GFM-WECS)under symmetrical grid fault have received little attention to date.In this paper,considering the dynamics of DC-link voltage,the transient stability and an improved control strategy of PMSG-based GFM-WECS are studied in detail.Firstly,considering the dynamic interactions between the machine-side converter and the grid-side converter,the large-signal equivalent model of GFM-WECS is established.Furthermore,a novel Lyapunov function is derived to evaluate the transient stability margin and instability boundary of GFMWECS during grid voltage sag.Additionally,the impacts of current-limitation control on the transient stability of GFM-WECS are revealed.Then,a stability evaluation index is proposed to evaluate the transient stability margin of GFM-WECS.Moreover,an improved control strategy is proposed to enhance the transient response characteristics and low voltage ride-through(LVRT)capability of GFM-WECS under symmetrical grid fault.Finally,simulations and experimental results are conducted to verify the effectiveness of the proposed control strategy.

关 键 词：Grid-forming(GFM) permanent magnet synchronous generator(PMSG) wind energy conversion system(WECS) DC-link voltage transient stability 

分 类 号：TM614[电气工程—电力系统及自动化]