Active Battery Balancing Circuit Based on Optimized Flyback Convertor for Large Lithium-ion Battery Packs

Abstract

This paper presents an active battery balancing circuit based on optimized flyback converter.Through modularization and hierarchical distributed design,the battery balacncing circuit can be easily expanded for large-scale battery packs. There are two improvements in the balancing circuit based on the flyback convertor. The first advantage of the balancing circuit increase the RCD clamp circuit, reducing the energy consumption,preventing the MOS transistor switch from being reversed by the flyback voltage. The second optimization apply for a predictive gate drive technology which replaces the flyback converter rectifier diode with a MOS transistor. It not only improves the efficiency of the battery balancing circuit,but also increases the adaptive dead-time, improving the system Stability. Finally, an experiment using 6 Lithium-ion batteries proves the feasibility of the balanced scheme proposed in this paper.