电动汽车电池温度加权PID控制
Weighted PID control of battery temperature for electric vehicle

针对纯电动汽车锂离子电池,建立了二自由度集中参数电池热模型,结合汽车行驶动力学模型,得到了电动汽车实际运行工况下电池的实时热响应模型。通过混合动力脉冲能力特性试验获得了电池热模型的参数,分析不同运行工况下电池的热响应,提出了基于加权比例积分微分法的再生制动控制策略。在满足制动安全性的前提下,通过调节电机制动力分配系数来实现电池充电电流的主动控制,从而控制生热源。在典型循环工况下,对比分析了再生制动控制策略与传统制动控制方案的电池热响应。分析结果表明:再生制动对电池的温升产生一定影响,汽车运行工况中再生制动的比例越大,电池温升越快; 再生制动控制方案能够有效地调节充电电流幅值,在美国激进高速循环工况的长下坡条件下,电池的最高温度比传统制动控制方案降低了2 ℃,电池荷电量提高了10%,因此,再生制动控制策略能在确保能量回收的同时兼顾电池温升的主动控制。
A two degrees of freedom lumped parameter thermal model of lithium-ion battery for electric vehicle was developed. In order to obtain the real-time thermal responses of battery, the thermal model was combined with vehicle driving dynamics model. The parameters of thermal model were obtained by hybrid pulse power characterization test. The thermal responses of battery under different driving cycles were analyzed. A regenerative braking control strategy based on the weighted proportion integration differentiation(PID)method was proposed, the active control of charging current for battery was realized by adjusting the distribution coefficient of braking force for electromotor on the premise of meeting braking safety, so that the generating heat source of battery was controlled. The thermal responses of regenerative braking control strategy and traditional braking control strategy were analyzed under the typical driving cycles. Analysis result indicates that regenerative braking has definite impact to the temperature rise of battery, the greater the proportion of regenerative braking under the driving cycles is, the faster the temperature rise of battery is. The regenerative braking control strategy can effectively adjust the charging current amplitude of battery, the highest temperature of battery reduces by 2 ℃ than the traditional braking control strategy under the long downhill condition in American radical high-speed driving cycles, and the charging capacity of battery increases by 10%. Therefore, the regenerative braking control strategy can ensure the energy recovery and actively control the temperature rise of battery at the same time. 14 figs, 23 refs