| Instead of the increasingly negative impact on fuel vehicle, energy-saving electric vehicle has become an inevitable trend. The battery which is the core component of the electric car is also the key factor to its entire performance. In addition, the function of this battery will directly influence the power and cruising ability of the vehicle. However, the battery charger acting as the energy supplementary part can meet neither the requirement of charging speed nor the requirement of charging effect at the current stage, and most of fast charging technologies which regarded as the improvidence of energy could be an attribute to the demand of depolarization by discharging, which is totally against the goal for the energy-saving technology.This thesis analyses domestic and international charging methods, charging control technologies, and the mechanism of charging process of the battery. Base on it, this thesis conducts the research on a new control strategy including the new fast charging method, the comprehensive charging and discharging control technology, mult-state monitoring and judgment, all of these to achieve energy-saving, fast, and intelligent design object. Besides, a fast charging and intelligent monitoring platform for battery has been designed and achieved by the hardware and the software. And the platform can charge with using different charging methods to different type of batteries. Ultimately, lead acid battery with the higher cost performance is picked by this thesis as its experimental object.In terms of design on energy-saving, the platform on the one hand improves the charger using traditional switching power supply, reduces the energy-consumption components and ASIC of switching power supply in circuit, and designs a new structure of charging power, which reduces the loss of energy and at the same time enhances the efficiency of power conversion. The platform on the other hand uses energy storage capacitors to recover the discharging energy for depolarizing, and charges the energy back to the battery in process of charge, so as to further achieve the goal of energy-saving.Concerning the fast charging, with studying on the theories of battery charging, the generation reason of polarization phenomena effectiveness of removing means, and the advantages of major charging methods, this thesis determines a fast charging method named voltage-controlled reflex multi-stage charging. In the meantime, this thesis has proofed the optional combination of various parameters in the new charging method by a sort of experiments, and also verified the new method can improve the charge efficiency, shorten the charge time and ensure the battery safe through the charge process through comparing the new method with the traditional one.With regard to the intelligence, the platform firstly designs two means of online measurement for internal resistance of battery, which works to identify the state of charge, state of health and invalidation of battery in real-time, the way of conducting the charging method and keeping battery in a safe matter. Secondly, the platform can neatly adjust voltage and current in the process of charging and discharging, and real-time monitor the voltage, current and temperature of key positions in circuit, and then judge them whether they are in the range of safe state or not. If they are out of the safe range, the platform immediately stops charging and alarms to ensure the safety of battery absolutely. Thirdly, the platform designs human-machine interaction means by lower-computer, which is easy to set parameters, observe and upload data. Finally, parameters of charging process and breakdown reasons are uploaded by upper-computer, which also can save the data and draw the curve.This topic determines a fast charging method, and designs a system platform which provides powerful means to research different battery with different charging method. It is highly practical and applicable to electrical vehicle.
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