变步长最大功率跟踪在双馈风力发电系统中的应用

Application of Variable Step Size Maximum Power Point Tracking Method in Doubly Fed Wind Power Generation System

在风力发电系统中,对于给定的风速达到最佳叶尖速比时,每条功率曲线均具有一个最大功率点(Maximum Power Point,MPP)。为了在不同的风速条件下均可产生最大的功率,必须对风力机的转速进行调节,以确保始终运行在最大功率点处。针对现有传统反馈控制的不足,提出了一种变步长最大功率跟踪策略,此方法可以根据输出功率变化的大小来改变扰动的步长值,克服了传统反馈控制成本高和固定步长的传统爬山算法稳定性、快速性难以兼顾的问题。同时采用定子电压定向控制,通过调节转子的励磁电流来调节定子发出的有功功率和无功功率。仿真实验结果证明了该方法的可行性。

In wind power generation system, for a given wind speed reached optimal tip speed ratio, each power curve has a maximum power point（MPP）. In order to produce the maximum power under different wind speed conditions, the speed of the wind turbine must be adjusted to ensure that the maximum power point is always running. Aiming at the shortage of existing traditional feedback control, a variable step size power tracking strategy is proposed. This method can change the size of the output power to change the size of the disturbance, and overcome the traditional feedback control costs and fixed step size of the traditional stability and speed of the stability and speed of the problem is difficult to take into account the problem. At the same time, the stator voltage directional control is used to adjust the active power and reactive power of the stator by adjusting the excitation current of the rotor. Simulation and experimental results demonstrate the feasibility of the proposed method.