串联电池组接触电阻故障诊断分析

开发资源节约型、环境友好型的电动汽车是当前全球汽车技术革命和产业转型的前沿阵地和技术制高点。为确保电动汽车行驶过程中的安全,避免电池发生功率衰退故障,采用一阶RC等效电路模型分析电池组的接触故障,并利用最小二乘法对模型参数进行识别,研究模型参数随电池荷电状态的变化规律。然后,在Simscape仿真模拟电池故障现象的基础上,分析出现电池电压变化异常的电池故障,得知其原因为接触电阻故障或内阻异常增加。最后,通过实验对比故障前后单体电池的电压、电流和内阻,总结得到电池发生接触故障的方法。

Series Battery Pack's Contact Resistance Fault Diagnosis Analysis

The resource-saving and environment-friendly electric vehicle is the forward position and technical commanding point in the process of global technological revolution and industrial transformation. To ensure the safety of electric vehicles when driving and avoid battery power fade fault, a first-order RC equivalent circuit model is used to analyze the connection failure of battery pack. The least squares method is adopted for parameter identification, and the variation of model parameters with SOC is studied. Next, based on the Simscape simulation of battery fault, the main reason for the battery failure with abnormal battery voltage change is the increase of contact resistance or internal resistance. Finally, how to determine the occurrence of contact resistance fault is experimentally explored, by comparing battery voltage, current and resistance before and after the fault.