改进的最大功率跟踪算法在变速风力发电系统中的应用

Improved maximum power point tracking algorithms used in variable-speed wind-power generation system

为最大限度地捕获风能,最大功率跟踪研究一直是风电技术行业关注的热点问题。本文从变速风力发电机组空气动力学模型入手,在最大功率跟踪算法———爬山搜索法分析的基础之上,引入模拟退火算法中概率函数的定义式,用于定义自适应步长,从而使跟踪开始时具有较好的动态特性和在跟踪结束时具有较好的稳态特性。在Matlab环境下,建立了变速风力发电系统模型,仿真分析了风速变化对输出功率的影响,改进的跟踪算法能够使输出功率最终稳定在新的工作点上,且具有较好的稳态特性和动态特性。

Based on the aerodynamic model of variable speed wind turbine and hill-climbing search, one of the Maximum Power Point Tracking （MPPT） algorithms, definition formula of probability function used in simulated annealing algorithm is referenced in the paper. It is used to define the adaptive step. The purposes are that dynamic characteristics is fine at beginning of searching stage, and steady state characteristics is more stable at the end of searching stage. The model of variable speed wind turbine and the effects of output power when wind speed is chan- ging are realized in Matlab. The conclusion is that improved algorithm can make output power stabilized at new state, and dynamic characteristics and steady state characteristics are stratifying.