The Study Of Charge Equalization Of Series-connected Batteries System

With development of electric, battery is used in many fields, for example, transportation, electric power system, correspondence, and so on. It becomes the key partial of these equipments. It affects directly the equipment life and the reliability.To realize a complete equalization charging system is this paper's primary intention. The paper elaborated principle and charging characteristic of lead-acid battery. How to choice charging method affect in performance and life of battery compares the earth, so this paper involved majority of charging methods in this field. Proposed balancing by voltage and electrically charged capacity, at the same time, explained effective of equalization by voltage.Key of the paper is research in charging equalization circuit, including the main circuit and control strategy. Design of main circuit influences performance of equalization. There are four methods, including by monomer battery's voltage, by cutting electric capacity, by multi- windings transformer and parallel DC/DC converter. Compared its advantage and disadvantage. Finally, using parallel DC/DC converter equalization to design a new circuit topology. The circuit includes many Buck-Boost units. It has some advantages, for example, lower loss and simple structure. Controlling the main circuit by Monolithic integrated circuit PIC16F873, certainly, including algorithm and arranges the procedure. We can observe change tendency of voltage of batteries that are charged. Voltage of batteries is consistent when charging over.