基于锂电池温度特性的混合动力系统能量管理策略研究

Study on Energy Management Strategy of Hybrid Power System Based on Lithium Battery Temperature Characteristics

为了提高重型串联式混合动力车辆的工作可靠性,从混合动力系统的组成架构入手,分析了系统的动力单元的特性和储能电池组的特性。而后基于Thevenin模型研究了电池组荷电状态和温度对电池的欧姆内阻和极化内阻的影响,由于电池温度对电池内阻有着显著地影响,提出了考虑电池温度特性的混合动力系统能量管理策略,即根据电池温度实时控制电池组的充电、放电电流,避免电池在极端温度下大倍率充放电引起的母线电压波动及电芯损坏等危害。实车道路测试对比了现有控制策略和所提出的控制策略,证明了基于电池温度的充放电功率控制策略的有效性。

In order to improve the reliability of heavy-duty hybrid electric vehicles, the paper analyzes the characteristics of the power unit and the energy storage battery pack from the composition of the hybrid system. Based on Thevenin’s model, effects of battery state and temperature on the ohmic internal resistance and polarization internal resistance of the battery were studied. Since the battery temperature has a significant influence on the internal resistance of the battery, the paper proposes a hybrid system strategy that considers the battery temperature characteristics. The energy management strategy controls the charging and discharging current of the battery pack in real time according to the battery temperature to avoid the damage of the bus voltage fluctuation and the cell damage caused by the large-rate charge or discharge of the battery under extreme temperature. The existing control strategy and the control strategy are proposed in this paper, and proves the effectiveness of the charge and discharge power control strategy based on battery temperature.