采用附加电源的均衡电路与容量自均衡方法

Equalization circuit with additional power supply and capacity self-balancing method

可重构均衡电路可以较好地兼顾元器件使用数目,均衡转换效率,方便地对电池组内任意单体电池进行均衡的需求,但对电池组进行均衡时负载电压会有波动。为在保留可重构均衡电路优点的前提下,较好地解决上述问题,提出了带有附加电源的可重构均衡电路。通过让附加电源代替被均衡的单体电池为负载供电,达到稳定负载电压的目的。在此基础上,文中还提出容量自均衡方法,充分利用电池容量的差异,间接地提高均衡速度。采用此均衡电路及均衡方法进行了均衡实验,实验结果表明,所提出的均衡电路不仅可以保留传统可重构均衡电路的优点,还可以在均衡过程中维持负载电压,并且配合所提出的均衡方法,相较于将电池组中最低荷电状态(State of Charge,SOC)的电池均衡至最高SOC值的传统方法,均衡速度提高了约44.8%。

The reconfigurable equilibrium circuit can take account of the number of components,equalize the conversion efficiency,and easy to balance each single cell in the battery pack,but the load voltage will fluctuate when the battery pack is balanced.In order to solve this problem,a reconfigurable equalization circuit with additional power supply is proposed in this paper.The purpose of stabilizing the load voltage is achieved by replacing the balanced cell with the additional power supply.On this basis,this paper also proposes a capacity self-balancing method,which can indirectly increase the equilibrium speed by making full use of the difference in battery capacity.The equilibrium circuit and equilibrium method are used to carry out the equilibrium experiment.The experimental results show that the proposed equalization circuit can not only retain the advantages of the traditional reconfigurable equilibrium circuit,but also maintain the load voltage in the equalization process,and match the proposed equilibrium method.Compared with the traditional method of balancing the minimum cell to the highest SOC,the proposed method has increased the equilibrium speed by about 44.8%.