Research And Design Of The Independent Solar Power System

In recent years, with intensify of energy shortage and environmental pollution, due to solar energy clean, security and resource adequacy and so on, it is increasingly becoming the public concern, but the solar energy conversion efficiency in the application of photovoltaic conversion becomes a major obstacle. In order to use solar energy resource for a greater extent and improve its efficiency, it is very important to research maximum power point tracking for solar power system.This paper firstly introduce the principle of solar cell, according to the theoretical model and mathematical model, the solar cell is modeled and simulated by MATLAB/SIMULINK tool, under the condition of standard parameters the V-I characteristics and V-P characteristics are analyzed through the simulation results, at the same time, under different light intensity and different temperature condition the output characteristics are compared.Secondly, maximum power point tracking(MPPT)technology is studied, the MPPT control principle is introduced. This paper adopts the perturbation and observation(P&O)to simulate after some common methods are compared in the diverse aspects, like application area,advantages and disadvantages. The results are analyzed and summarized. Based on fuzzy control MPPT algorithm was proposed by the data further extraction and research. The variable step length P&O is simulated, the simulation results show that, the maximum power point can be stabilized and avoid maximum power point shock in the fixed P&O. It is able to find a new maximum power point quickly when the environmental parameters change and the result demonstrate excellent tracking performance.Finally,the independent solar power system platform are designed with C8051F040 as the core. It is composed of data acquisition module, man-machine interactive module and charging and discharging module. Among them, battery charging and discharging state is controlled by the charging and discharging module; in the data acquisition module, important data in parts are acquired as control basis, like the temperature,humidity and light intensity are collected to prepare the further analysis; All kinds of data in the system are displayed by the LCD in the man-machine interactive module.