The Study Of MPPT Type Photovoltaic Controller

The important research in the photovoltaic power generation system is how to improve the conversion efficiency of the solar cell. Power Point Tracking Maximum (MPPT) is an effective means to improve the efficiency of photovoltaic solar cells Based on the research of MPPT algorithm, a photovoltaic controller using the MCU of ATMEL Company is designed in this paper. The paper’s main work is as follow:Firstly, the working principle of the solar cell is described, and the mathematical model of the photovoltaic cell is introduced. The simulation model is built by MATLAB/Simulink simulation software. The output characteristics of photovoltaic cells under different light and temperature conditions were compared and analyzed.Secondly, the principle of MPPT algorithm is introduced, and analyzes several principle of MPPT algorithms is analyzed. Based on comparing the advantages and disadvantages of different algorithms, the design of the controller using three point center of gravity method is introduced. To improve three point center of gravity method, the improved three point center of gravity method has been presented.Thirdly, the hardware of MPPT photovoltaic controller is designed and he software program is compiled. Hardware circuit using BUCK circuit as the main circuit. Using XMEGA series of microcontroller of ATMEL Company as the main control chip, it is responsible for sampling and processing the voltage and current data of the solar battery. In the software, the efficient tracking of the maximum power point of the solar panels is realized by the improved three point center of gravity method.Finally, the experimental platform based on Off-grid PV control system is set up. The effectiveness of the method is verified under different environmental conditions, and the results show that the MPPT algorithm can effectively overcome the shock, taking into account the requirements of the speed and accuracy, can accurately track the maximum power point, and improve the conversion efficiency of solar cells.