基于扰动观察法的MPPT控制优化策略

Optimized MPPT Control Strategy Based on Perturbation and Observation Method

为了提高光伏发电系统的充电效率,系统控制器采用高性能低功耗的ATmega16单片机为核心,通过调节PWM波占空比实时改变Buck变换器的输出电压,采用扰动观察法的MPPT控制策略,实现对光伏发电系统最大功率点的跟踪。针对扰动观察法跟踪过程中可能由于快速扰动导致功率振荡和误判的问题,系统对MPPT算法进行优化,并通过友好的人机界面实时显示最大功率曲线图。测试结果表明,该方法能够保证光伏发电系统快速、稳定、精确地跟踪最大功率点,提高了充电效率。

In order to improve the charging efficiency of photovoltaic system,the system controller takes the high-performance low-power ATmega16 microcontroller as a core,changes the output voltage of Buck converter in real-time by adjusting the PWM duty cycle,and uses the MPPT control strategy of perturbation and observation method to achieve tracking of maximum power point of the photovoltaic power generation system.The MPPT algorithm was optimized to solve the problems of power oscillations and misjudgment probably caused by rapid perturbation during the tracking with perturbation and observation method.The real-time maximum power graph of the system is shown by a friendly man-machine interface.The testing results indicate that the method can ensure PV system to realize MPPT fast,steadily and accurately,and improve the charging efficiency.