太阳能池板最大功率跟踪技术的研究

Study on MPPT Technology of the Solar Cell

针对光伏发电技术中太阳能池板的最大功率工作点展开研究,阐述了太阳能池板的发电原理及数学模型的建立。针对太阳能池板输出特性及最大功率跟踪的方法,对比分析了传统的恒定电压法、扰动观察法和电导增量法,总结优缺点后提出了改进型变步长电导增量法。在距离最大功率点较远的时候,采用较大的步长,缩减追踪时间,在最大功率点附近时,减小步长,增大追踪精度。利用Matlab仿真软件对传统和所提出的变步长电导增量法进行了仿真,仿真结果对比证明变步长增量法收敛速度快,效果良好。最后通过光伏发电并网试验系统进行了4.4 kW太阳能池板最大功率跟踪技术实验,跟踪实验误差为3%,符合微电网技术要求。

In this paper, a study on photovoltaic solar cell technology maximum power point tracking （MPPT） is pres- ented through illustrating the generating principle of solar cell and how to create its mathematical model. In view of the output characteristics of the solar panels, the traditional method of constant voltage, perturb and observe algorithm and incremental conductance method are compared. On the basis, an improved variable step size INC method is proposed that means using a larger step size to reduce the time tracking when far from the maximum power point while reducing the step size to increase the tracking accuracy when near the maximum power point. Matlab is used for the simulations of the traditional method of constant voltage and the improved variable step size INC method. The simulation results show that the improved variable step size INC method has good effect because of its fast convergence. Finally, the ex- periment on MPPT of 4.4kW through photovoltaic power generation and network test system is carded on. The error of it is 3 % proves that it is in line with the micro-grid technology requirements.