Research On Charge-Discharge Divice Of Storage Battery Based On PWM Technology

Lead-acid storage battery is widely used in every field because of its outstanding advantages. It is urgent to solve AC harmonic which comes from electronic device. The quickly development of modern power electronics and control theory provide broadly foreground for charge-discharge system of storage batter. Especially three-phase converter which has the advantages of bi-directional power flow, low AC harmonic and unit power factor, becomes the researching hotspot in the field of power electronics.It is significative to use three-phase PWM converter in charge-discharge device to eliminate harmonic pollution and improve power efficiency after deeply studying its theory.The studying object in this thesis is charge-discharge lead-acid storage battery device using in locomotive. Firstly, the demands of charge-discharge device are analysed. The total scheme is designed according to the performances of charge-discharge device. and three-phase converter is selected as main circuit, and its mathematical model is studied. The Parameters selection of the device are theoretically analyzed, which influence the performances of charge-discharge device .Then the results of simulation validate the theoretical analysis.Secondly, the control scheme is designed based on control targets. After analysing several control methods, SVPWM arithmetic is selected to implement PWM wave, and its detail process is introduced. Current dual control is designed base on dynamic and static performances. The typical I model is used to design inner current controller in order to obtain quickly following performance. The typical II model is used to design outer current controller in order to obtain high resistive performance. Then the results of simulation validate the theoretical analysis.At last, the whole simulation module of charge-discharge system is built up under the powerful MATLAB/SIMULINK platform. The results of simulation satisfy the performances of system, which testifies the feasibility of the designing scheme and validity of the designing parameters.