基于模糊PI控制与电导增量法的光伏MPPT跟踪技术

Photovoltaic MPPT Tracking Technology Based on Fuzzy PI Control and Conductance Increment Method

为了解决光伏MPPT算法跟踪速度和精度的问题,针对传统输出电导增量法所产生的系统振荡和误判等问题,提出一个改进型的控制算法。通过将单模糊控制和电导增量法相结合的混合计算,能够使工作地点离最大输出功率点更接近,从而减少了在最大功率点时容易振荡的问题。通过分析系统光伏电池的工作特点,从而建立了光伏电池输出功率的数学模型,并进一步在Matlab/simulink环境下建立了仿真模型,经过对单模糊控制定步长电导增量法与单模糊控制变步长电导增量法的比较,结果表明所提出的方法能够增强了系统追踪的稳定性,从而减小了系统振荡所带来的电能损失,并在日照强度变化时也可以较快地追踪到最大功率点。

In order to solve the problems of tracking speed and accuracy of photovoltaic MPPT algorithm, an improved control algorithm can be provided to solve the problems of system oscillation and misjudgment caused by the traditional output conductance increment method.By combining single fuzzy control and conductance increment method, the working place can be closer to the maximum output power point, so as to reduce the problem of easy oscillation at the maximum power point.By analyzing the working characteristics of the photovoltaic cell of the system, the mathematical model of the output power of the photovoltaic cell is established, and the simulation mode is further established in the environment of MATLAB/Simulink.Through the comparison between the single fuzzy control constant step conductance increment method and the single fuzzy control variable step conductance increment method, the results show that the proposed method can enhance the stability of the system tracking and reduce the power loss caused by the system oscillation, The maximum power point can also be tracked quickly when the sunshine intensity changes.