Study On The MPPT And Automatic Tracking Control Of PV System

Along with the global industrialization and the increasing depletion of energy, solar energy becomes the focus of people's attention because of its unique advantage. Governments have taken major initiatives to encourage and support the development of solar energy. In recent years, photovoltaic power generation has been rapid development in the international scope. At present, PV battery photoelectric convert efficiency is low and expensive. The cost of PV is too high, which can not compared with the traditional forms of power generation, such type influenced the development of PV power industry. In order to reduce the cost of PV power, the experts and scholars at home and abroad are continuing to explore more mature approach. Tracking method using automatic tracking mode keeps light vertical irradiate photovoltaic array surface. It is an effective way to improve the utilization ratio of solar energy and reduce the cost. Studing precise PV automatic tracking device can make the PV array receive more solar energy and increase the amount of PV power generation.According to the study of PV tracking system status and prospect, this paper described the characteristics of PV tracking system and its main structure, built a PV array simulation model based on the equivalent circuit of PV cells and verified the correctness of the model. This paper compared with the advantages and disadvantages of classical MPPT control method and its improved algorithms. Meanwhile built the simulate mode of maximum power point tracking control based on the fuzzy control using MATLAB-Simulink. Proposed adaptive duty cycle perturbation method based on fuzzy control, proved the superiority of this method comparing with the simulation results of tradition DRP, adaptive duty cycle perturbation method and the adaptive duty cycle perturbation method based on fuzzy control.This paper gave the sun operation law and sun angle calculation method and CMAC-PID compound control method was applied to the tracking control system based on the system function analysis, meanwhile the feasibility of this method was verified by simulation.This paper completed the hardware designs of automatic tracking system, such as light intensity detection circuit, motor drive circuit. At the same time, this paper gave the main programme of this system and the subroutines of electro-optical and sun trajectory tracking.