并联式混合动力电动汽车全局优化控制

Global Optimization Control of Parallel Hybrid Electric Vehicle

以一种充电保持型并联式混合动力电动汽车(PHEV)为研究对象,基于其整车及动力总成相关数学模型建立了以整个行驶工况消耗的总燃油量最小为目标的系统目标泛函,以及相关的机械特性、蓄电池电量保持等约束条件方程.然后采用Lagrange乘子法将有约束的极小值问题转化为无约束的极小值问题进行求解,得到PHEV的全局优化控制策略.最后基于Matlab/Simulink建立整车仿真模型,在几种不同的循环工况中对获得的全局优化控制策略进行仿真验证,并与采用瞬时优化控制策略得到的仿真结果进行比较.结果表明该全局优化控制策略切实可行,所获得的整车燃油经济性与采用瞬时优化得到的相比有所改善.

With a charge-sustaining PHEV （Parallel Hybrid Electric Vehicle） as the research subject, a system target function with minimum global fuel consumption in the whole driving cycle is set up based on the mathematical models related to the vehicle and its powertrain. The corresponding mechanical and battery constraint functions are also established. Then, the constrained minimum problem is transformed into an unconstrained minimum one, which is solved by using the Lagrange multiplier method, with a global optimization control strategy being obtained, Moreover, a vehicle simulation model is built up based on Matlab/Simulink to verify the proposed strategy in several typical driving cycles. The simulated results are finally compared with those obtained by the instantaneous optimization control strategy. It is then concluded that the proposed strategy is valid and can help save fuel.