Design Of Charge And Discharge System For Lithium Battery Based On Series Parallel Resonant Converter

Lithium battery has important applications in the fields of distributed generation,electric vehicle,medical and health,aviation and spaceflight,etc..Lithium battery energy management is a hot research topic at present.The charging and discharging circuit of lithium battery and its control strategy are the key components of the battery energy management system.The current charging and discharging circuit topology has a further improvement in efficiency,power density,reliability and other aspects.In this paper,a lithium battery charging and discharging system based on series parallel resonant converter is proposed,which is based on the characteristics of the lithium battery:1 according to the charging and discharging characteristics of lithium battery to choose four step charging strategies;analyzed characteristics of LCC series parallel resonant converter,and choose the converter as the main topology of charging system of lithium ion batteries;choose control scheme of charging system based on the selected charging strategy.2 Analysis of the shortcomings of LCC series parallel resonant converter,and on the basis of the LCCL series parallel resonant converter,and a detailed analysis of the working principle of the converter;established the mathematical model,the analysis of the impact of working parameters on the resonant characteristics and work characteristics.3 according to the discharge characteristics of the lithium battery,the discharge system based on the LCCL series parallel resonant converter is designed,and the control method of the discharge system is presented.4 the implementation methods of lithium battery charging and discharging system are analyzed,including the important control circuit design method and the flow chart of software realization.5 the charging and discharging system of lithium battery is simulated,and the hardware circuit is built on the basis of the experiment.The performance of the LCCL series parallel resonant converter and the charge and discharge system of lithium battery are verified.