中文摘要：

为了提高垂直轴永磁直驱风力发电系统控制的鲁棒性和自适应性,针对大范围风速扰动和系统参数不确定的特点,应用非线性干扰观测器（NDO）实现垂直轴风力机气动转矩的估计,再结合反演（Back-stepping）控制方法设计发电最大功率跟踪（MPPT）控制器。控制器采用基于最佳转速跟踪的MPPT策略,通过逐步选择虚拟控制量和构造李雅普诺夫函数,使每个被控子系统具有良好的渐近特性,进而得到整个系统在大扰动下的全局渐近控制律。利用Matlab/Simulink建立系统的仿真模型,通过与PID控制器的对比实验,验证了反演控制器设计的正确有效性。

英文摘要：

For overcoming the disadvantages of wide range wind power perturbation and model parameter uncertainties,a novel maximum power point tracking（MPPT） controller for vertical axis wind power generation system is designed using back-stepping control method.The MPPT controller adopts wind turbine＇s optimum rotational speed tracking algorithm,and the wind turbine＇s dynamic aerodynamic torque is estimated by a nonlinear disturbance observer（NDO）.According to the back-stepping controller design approach,virtual control signals and Lyapunov functions are constructed step by step.By employing Lyapunov stability theorem,back-stepping control law for each subsystem is worked out,thus,the global asymptotical stability for the overall system that all virtual control signals involved are guaranteed.The control system is simulated using Matlab/Simulink software,which is compared with conventional PID control method.The simulation results verify the correctness and effectiveness of the back-stepping controller.