Research Of Battery Maintenance Equipment With Wide Voltage Range Based On Bridge Converter

ABSTRACT:The Electric Vehicle develops rapidly in recent years, and battery is the only source of pure Electric Vehicle. The battery needs to be charged quickly and safely. And it is important to maintain battery in regularly by full charging/discharging. The performance of charging and discharging system affects not only the battery performance and life-span, but also the grid's power quality.With the development of power electronic device and control technology, the battery maintenance equipments have three characters of high frequency, high efficiency, and charging/discharging function combination. The battery test and maintain equipments should have the ability of output voltage and current with wide span, in order to satisfy the requirements of both single cell and battery-pack.A battery maintenance equipment, which is base on a voltage source PWM Rectifier in series with a bi-directional DC/DC converter, is designed in this dissertation. It implement bidirectional power flow, sinusoidal current control and unit power factor control in grid side as well. Its output voltage and current are stable, ripple are less.This paper designs the battery maintenance equipment's main circuit parameter and builds up the model in MATLAB/Simulink. A hardware and software control system of bi-directional DC/DC converter based on MC9S12D64 is designed. The result of experiment shows that efficiency is higher than 85%, power factor is higher than 99%, and the ripple of voltage and current is lower than 1% in full load. And the battery maintenance equipment can be realized DC 3V-100V,5A-100A wide range of stable output. It satisfies the design requirements and validates the correctness of the design.