多机系统锁相环振荡模式的数值域稳定判据  

Numerical range stability criterion for PLL oscillation mode of multi-converter system

作　　者：王冠中 王巍[1] 史千弘 马锐 郝全睿[1] 丁磊[1] WANG Guanzhong;WANG Wei;SHI Qianhong;MA Rui;HAO Quanrui;DING Lei(Key Laboratory of Power System Intelligent Dispatch and Control,Ministry of Education,Shandong University,Jinan 250012,China)

机构地区：[1]山东大学电网智能化调度与控制教育部重点实验室,山东济南250012

出　　处：《电力自动化设备》2024年第10期85-91,139,共8页Electric Power Automation Equipment

基　　金：国家电网有限公司科技项目(SGSDYT00FCJS2200325)。

摘　　要：针对锁相环变流器多机系统的振荡问题,提出了面向多机系统锁相环振荡模式的数值域稳定判据,完善了广义Nyquist判据的可解释性。根据实际工程运行方式,通过保留变流器导纳矩阵中主导振荡的关键元素完成模型简化,进而利用矩阵数值域代替广义Nyquist判据,将多机系统的频域导纳矩阵等效为单机系统传递函数,以其Nyquist曲线不包围点(-1,0)作为多机系统稳定的充分条件。分析结果揭示了多机系统小干扰稳定性具有不同单机外特性相互折中的现象,为实用化的电网强度分析奠定了理论基础。通过特征值分析和时域仿真说明了所提方法的有效性。For the oscillation of phase locked loop(PLL)multi-converter system,a numerical stability criterion for PLL oscillation mode of multi-converter system is proposed,and the poor interpretability of generalized Nyquist criterion is supplemented.Based on the actual operation modes in the engineering,the model is simplified by retaining the key elements dominating oscillation in the admittance matrix of the converter.With the numerical range of matrix instead of the generalized Nyquist criterion,the frequency-domain admit⁃tance matrix of the multi-converter system is equivalent to the transfer function of the single-converter system.Therefore,the Nyquist curve do not enclose the point(-1,0)serving as the sufficient condition for the sta⁃bility of multi-converter system.The analytical result reveals that the small disturbance stability of the multi-converter system has the rule that the external characteristics of single-converter compromise each other,which can provide a theoretical basis for the analysis of the practical grid strength.The validity of the pro⁃posed method is illustrated by eigenvalue analysis and time-domain simulation.

关 键 词：变流器并网系统 小干扰稳定 导纳凸组合 数值域 广义Nyquist判据 

分 类 号：TM46[电气工程—电器] TM712