In recent years,medium and high frequency oscillations have occurred in many VSC-HVDC trans-mission projects at home and abroad,which affects the security and stability of power system operation.Aiming at the medium and high frequency oscillation problem in the VSC-HVDC transmission system,the establishing methods of impedance model and state space model for VSC-HVDC converter station,and the mathematical model for AC system are all expounded.The principles and methods of system stability analy-sis using impedance analysis method and eigenvalue method are described.The influence of voltage feedfor-ward,current inner loop,phase-locked loop and circulating current control on the impedance characteristics of the converter is analyzed based on the converter impedance model.The existing medium and high fre-quency oscillation suppression strategies and their effects on the dynamic performance of the VSC-HVDC transmission systems are summarized,and the harmonic protection methods are introduced.The research on the suppression measures for medium and high frequency oscillation is prospected,and suggestions for fu-ture research fields are given.
关键词
阻抗模型/状态空间模型/抑制策略/中高频振荡/动态性能/谐波保护/柔性直流输电
Key words
impedance model/state-space model/suppression strategies/medium and high frequency oscilla-tion/dynamic performance/harmonic protection/VSC-HVDC transmission
维普
万方数据