In wind power generation with complicated wind conditions, a reliable and high effective maximum power point tracking (MPPT) strategy is needed to fully make use of wind energy and improve generation efficiency.On the basis of studying traditional methods, this paper presents an improved strategy of variable step three-point comparison method with controllable parameters.When power value changes below the defined value, this strategy keeps the rotating speed of generator to suppress power oscillation, while in the vicinity of maximum power point it reduces the step size exponentially so as to ensure precision and stability of MPPT.Parameters of the controller are selected by empirical method and Hua Luogeng optimization method that can meet requirements of most occasions.This strategy doesn`t depend on wind speed measurement device and it has been verified to be provided with good control effect.%在风况较复杂的风力发电中,为了使风电机组充分利用风能,提高发电效率,需要一套可靠高效的最大功率点跟踪(maximum power point tracking,MPPT)策略.在研究传统方法的基础上,提出一种参数可控的变步长三点比较法改进策略.当功率变化在界定值以下时对转速采用不操作的方式抑制功率振荡;而在最大功率点附近指数倍削减步长,从而保障最大功率跟踪的精度和稳定性.控制器的参数采用经验法与华罗庚优选法选取,可满足绝大多数场合的要求.该种策略不依赖风速测量装置,经MATLAB软件仿真验证,具有良好的控制效果.
展开▼
