Research on Active Equalization Topology Based on the Multi-input Transformer

T Targeted at the existing complex structure, numerous switching components and high control difficulty of existing equalization circuit of lithium-ion battery series, this paper proposes an active equalization topology circuit based on multi-input transformer. The equalization circuit is composed of battery module, fly-wheel diode, MOS transistor and transformer. Based on the classification and summary of battery equalization topology, this paper analyzes and studies the principle of active equalization topology based on multi-input transformers. The working principle is simple, with the use of fewer devices. Matlab/Simulink is applied to build a model for simulation analysis, and the simulation results show that switching frequency and series module capacity have an impact on the equalization effects. The equalization comparison rate simulation of the series capacitor module and the single module indicates that the proposed topology has a faster equalization speed for multiple modules. The simulation results verify the validity of the proposed topology in voltage equalization between different modules.