基于热模型的动力电池热故障诊断系统

Power Battery Thermal Faults Diagnostic System Based on Thermal Model

为提高车载动力电池热管理系统的可靠性,使电池温度维持在合理的范围内,根据镍氢电池的结构及传热学原理,建立了电池的热模型,实现了电池内部及表面温度的在线预测.通过模型预测温度与实际温度的对比,对电池温度异常状况进行在线诊断,并将诊断信息通过控制器局域网(CAN)通信传送给整车控制器,使整车及时对故障做出响应.试验结果表明,该系统能准确及时地诊断风机故障、电池剩余容量(SOC)过高及电池过充故障,有效避免了因热故障引起的电池过温.

To improve the performance of battery thermal management system, a battery thermal model was built based on the analysis of battery structure and the thermal conductive theory. With the help of this model, the internal and surface temperatures of the battery were predicted online. By comparison of predicted and measured temperatures, the thermal faults were diagnosed. The battery management system transmits diagnostic information to the whole car control unit to make the car react in time. The experimental results indicate that this system is able to detect the thermal faults such as fan failure and battery overcharging in time and exactly, which effectively avoids battery overheat under high temperature conditions.