基于并联拓扑的锂电池组充电电路设计及Proteus仿真

Lithium-Ion Battery Pack Charging Circuit Design and Proteus Simulation Based on Parallel Topology

鉴于锂电池组在循环充放电过程中存在温升、过充放及单体电压不均衡等现象,会导致电池组单体间容量差异化增大,进而降低其使用寿命。为此,结合锂电池充放电需求,基于并联拓扑和均衡理论,采用“PWM整流+反激式间接直流变换+Buck降压斩波”原理设计充电电路,并通过ADuC812单片机实现电压、电流、温度的全程实时监控。最后,以6700901型磷酸铁锂电池组(LiFePO4)作为实验对象,利用Proteus软件对锂电池组充电电路、保护电路及均衡电路分别进行了仿真。结果表明单体电压间极差由充电前的0.065 V降至0.003 V,验证了充电电路的可行性与较好的均衡效果,保护电路亦达到预期效果。

In view of the lithium battery pack in the cycle of charging and discharging process,there are temperature rise,overcharging and discharging,single-unit voltage imbalance and other phenomena,which will lead to the increase of capacity differentiation between the battery pack single-unit,and thus reduce its service life.For this reason,the demand for lithium battery charging and discharging being combined,based on parallel topology and equalisation theory,the principle of"PWM rectifier+flyback indirect DC converter+Buck buck chopper"is adopted to design the charging circuit,and the whole real-time monitoring of voltage,current and temperature is achieved through ADuC812 microcontroller.Finally,6700901 lithium iron phosphate battery pack(LiFePO_4)is adopted as an experimental object,the lithium battery pack charging circuit,protection circuit and equalisation circuit are simulated by using the Proteus software.The results show that the voltage difference between the monomer is reduced from 0.065 V before charging to 0.003 V,which verifies the feasibility of the charging circuit and the equalisation effect,and the protection circuit also achieves the expected effect.