摘要
风电并网所引起的次/超同步振荡研究多集中于小信号模型分析,较少考虑遭受大扰动后限幅等非线性影响.基于单边限幅的描述函数与广义Nyquist判据,对正阻尼直驱式永磁同步发电机(PMSG)限幅环节间歇饱和引起的切换型次/超同步振荡进行分析.首先给出并网PMSG状态空间简化模型并分析其小干扰稳定性;其次发现一种大扰动后并网PMSG因不对称单边d轴电流限幅间歇饱和引起的新型切换型振荡现象;再次结合并网PMSG网侧变流器的频域模型以及单边限幅的描述函数,给出含限幅环节的PMSG系统近似分析模型;最后结合广义Nyquist判据,近似分析不同限幅值和参数下的振荡频率,并解释该种振荡频率随限幅上限降低而增加的现象.
The research on subsynchronous/supersynchronous oscillations caused by wind power integrated system mainly focuses on small-signal model analysis. Nonlinear effects such as amplitude limit after large disturbance are rarely considered. Based on the description function of unilateral limit and the generalized Nyquist criterion,the switching subsynchronous/supersynchronous oscillations caused by intermittent satura⁃ tion of limiting link in positive damped direct-drive permanent magnet synchronous generator(PMSG) is ana⁃ lyzed. Firstly,the state space simplified model of integrated PMSG is given and its small disturbance stabi-lity is analyzed. Secondly,a new switching oscillation phenomenon caused by asymmetric unilateral d-axis current limiting intermittent saturation of PMSG after large disturbance is found. Thirdly,combined with the frequency domain model of grid-side converter of PMSG and the description function of unilateral limiting, the approximate analysis model of PMSG system with limiting link is given. Finally,combined with the gene-ralized Nyquist criterion,the oscillation frequencies under different limiting values and parameters are appro-ximately analyzed,and the phenomenon that the oscillation frequency increases with the decrease of the upper limit is explained.
作者
张哲
乔登科
汪云涛
薛静玮
林毅
薛安成
ZHANG Zhe;QIAO Dengke;WANG Yuntao;XUE Jingwei;LIN Yi;XUE Ancheng(State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources,North China Electric Power University,Beijing 102206,China;North China Branch of State Grid Corporation of China,Beijing 100053,China;Economic and Technology Research Institute of State Grid Fujian Electric Power Co.,Ltd.,Fuzhou 350012,China)
出处
《电力自动化设备》
EI
CSCD
北大核心
2023年第9期33-38,共6页
Electric Power Automation Equipment
基金
国网福建省电力有限公司科技项目(52130N20000J)。
关键词
PMSG
限幅环节
间歇饱和
次/超同步振荡
描述函数
PMSG
limiting link
intermittent saturation
subsynchronous/supersynchronous oscillations
de⁃scription function
