直驱型风力发电系统MPPT研究

The MPPT strategy of direct-drive wind power system

基于中小功率风力发电系统中占空比扰动法实现最大功率点跟踪(maximum power point tracking,MPPT)时,在最大功率点附近由于占空比不稳定而导致输出功率出现振荡的现象,提出了改进方法,即在最大功率点附近扰动时采用一种新的变步长方法,不断减小占空比扰动步长,直至稳定于最大功率点.利用Matlab/Simulink软件对系统进行仿真,结果验证了该方法的可行性以及该控制系统良好的快速性和稳定性.

In medium and small power wind power generation systems, duty factor perturbation method is often used to achieve maximum power point tracking, and the method maybe not stable near the maximum power point, so the output power near the maximum power point appears oscil- lation. To solve this problem, the paper gives an improved method which uses a new variable step size method to reduce duty cycle perturbation step near the maximum power point until the corre- sponding maximum power point duty ratio is stable. Simulation with the software of the Matlab/ Simulink proves that this system has better rapidity and stability.