基于反激式直流变换器的电池均衡系统仿真研究

Research on Modeling and Simulation of Battery Equalizer Based on Flyback DC/DC

摘要:

针对电动汽车锂离子电池组在工作过程中出现的能量不一致现象,设计了一种基于反激式直流变换器的主动均衡电路,包括电源转换、信号采集、驱动电路以及均衡器4个模块。研究了均衡系统的拓扑结构和工作原理以及控制策略,阐述了反激式直流变换器与锂离子电池的建模方法,针对电池组8种典型的非均衡工况,进行了混合策略下的5 kHZ高频仿真实验,实验用电池SOC从44.3%到55.7%均有涉及,仿真与实验结果误差均在10%以内,验证了PSIM仿真电路与同轴多绕组变压器与电池建模方法以及混合控制策略的正确性。

Abstract:

For the imbalance phenomenon of battery packs in electric vehicles, a new charge equalization converter using flyback DC/DC in electric vehicle battery system was designed, The principal and circuit of the equalization system were particularly presented, as well as three balancing strategies name Top , Bottom and mixture balancing . The method of modeling for flyback DC/DC and Li-ion battery was described, and the PSIM simulation model of the equalization system was built. The mixed strategy was simulated under 5 kHz high frequency condition , and the SOC of experimental batteries were involved from 44.3% to 55.7%. For all the errors between simulation and experiment results were within 10%, the simulation circuit and modeling methods were verified as well as the correctness of the hybrid control strategy.