| Traditional non-renewable energy resources tend to be exhausted, while the demand of energy increases. However, environment pollution is also an important problem to human on the earth. Solar energy, which is a kind of innovative renewable energy resource, is prospective.Solar energy can be widely used in electric vehicles (EV), as it is free of emission and pollution. Solar EV is a combination of photovoltaic (PV) and EV technology, which replaces the traditional fossil fuel with innovative green energy resource. As a result, solar EV is known as the trend in development of automobiles in the future.This work is supported by Technology & Development Project of Jilin Province, Microfluidic solar vehicles (20080353), Oct,2009. The main purpose of this research is to take solar batteries and automotive lead-acid batteries as experimental subjects, and to find the best way of energy conversion and use advanced means of the current to achieve the design object.First of all, an electric golf-car and widely used lead-acid batteries are chosen to study on in this work. Bttery testing system is employed to monitor battery's parameters, such as charging voltage, charging current, capacity of battery, discharging voltage and discharging current, etc. Parameters of the PV control system matching with the experimental subject are confirmed, based on data analysis.Secondly, a theoretic math modeling is constructed for research on the output performance of solar batteries. Different MPPT (max power point tracking) algorithms are analyzed and compared. The scheme of rapid charging for lead-acid batteries has been provided as a combination of stage-charging method and conductance increment algorithm. The DC/DC transmission technology used in the control system is also built up in this article.Thirdly, in order to meet the requirements of intelligent control of the vehicle, the AVR microcomputer is chosen as the CPU of the DC transmission system. It is convenient to improve the control programs and to connect to the CAN bus on a vehicle, because of high calculate speed, low energy cost, large memory capacity, high extensibility and rewritable ability of AVR microcomputers. Programming of the management system has been carried out and simulated using Proteus and ICCAVR.Then, the solar power test system is used to collect the data of the actual temperature and the sunshine intensity in Changchun, and the collected data has been employed in simulations of the sub-part and whole system of the PV management system using Matlab/Simulink. Simulation results show that use of this PV management system can promote the output power of PV batteries by up to about 7.78% than that of PV batteries without the management system. And when the light intensity remains stable, the system tracking performance is relatively stable, too. On the other hand, the maximum power tracking system can quickly respond to the change of light intensity, meeting the design requirementsFinally, solar battery modules are fixed onto the Solar EV. We also rebuild the total construction of the EV to optimize the mass distribution. Based on the theoretical research and system simulation using the AVR microcomputer (ATmegal6-16AU chips), a prototype of the management system for a solar photovoltaic electric vehicle has been designed, produced and experimented. Experiment results show that this management system can determine the system status accurately, and select the correct method to charge the batteries by solar energy quickly, efficiently and safely.
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