【摘要】 相比于工频和直流输电方式，分频输电方式凭借其在输电损耗、建设成本等方面的优势，成为大规模远距离海上风电汇集送出的重要解决方案。但是，分频海上风电系统的稳定性研究，尤其是在系统运行典型大干扰背景下的分析较为欠缺。通过建立分频海上风电系统高阶非线性的状态空间模型，采用扇区非线性方法处理模型中的高阶非线性部分，构建了系统的Lyapunov能量函数，计算了相应的稳定区域。在此基础上，基于Lyapunov稳定性定理，分析了多种典型大扰动工况下永磁直驱风机和陆上模块化多电平矩阵式换流器（modular multilevel matrix converter,M3C）之间的交互稳定性问题，并基于稳定区域的比较，分析了系统主电路和控制部分参数对大干扰稳定性的影响规律，给出了系统参数优化和稳定性提升策略。最后，通过MATLAB/Simulink仿真算例对Lyapunov能量函数和稳定区域的正确性进行了验证。更多还原

【Abstract】 The fractional-frequency transmission method has become an important solution for large-scale long-distance offshore wind power collection and transmission due to its advantages in transmission losses and construction costs compared with power frequency and direct current transmission methods. However, the stability research of fractional-frequency offshore wind power systems, especially the analysis under the background of typical large disturbances in system operation, is lacking. A high-order nonlinear state space model of the fractional-frequency offshore wind power system is proposed, and the sector-based nonlinear method is used to deal with the high-order nonlinear part of the model; the Lyapunov energy function of the system is constructed, and the corresponding stable region is calculated. On this basis, based on Lyapunov stability theorem, the interactive stability problem between the permanent magnet direct drive fan and the onshore modular multilevel matrix converter(M3C) under various typical large disturbance conditions is analyzed, and based on the comparative analysis of the stable area, the influence rules of the main circuit and control parameters of the system on the stability under large disturbance are given, which is helpful for system parameter optimization and stability improvement. Finally, the correctness of the Lyapunov energy function and stable region is verified through MATLAB/Simulink simulation examples.更多还原