一种单行星排功率分流式混合动力系统构型优化设计方案

Optimization Design Scheme of Power-split Hybrid Electric Powertrain Configuration with Single Planetary Gear

基于行星齿轮机构的功率分流式混合动力系统可利用双电机分別对发动机进行转速调节和转矩补偿,从而使得混合动力汽车(Hybrid electric vehide, HEV)的燃油经济性和排放性能得到显著提升。然而,单行星排功率分流式混合动力系统在行驶过程中会频繁产生功率循环现象,降低了系统整体工作效率。为了进一步提升燃油经济性,提出一种单行星排功率分流式混合动力系统构型优化设计方案。首先,对单行星排功率输出/输入式混合动力系统的运行特征以及拓扑结构进行分析,拆分并重组两种拓扑结构的连接关系,以生成基础拓扑结构方案。其次,基于基础拓扑结构方案探索全部的可行性拓扑结构,并对可行性拓扑结构进行组合以生成新的构型方案。最终采用基于动态规划(DP)算法的全局最优的控制策略对所生成的构型方案的最佳经济性和最佳动力性能进行仿真分析。结果表明,所提出的单行星排功率分流式混合动力系统构型优化方案能够有效提升整车综合行驶性能。

The power-split hybrid electric powertrain(PHEP) based on planetary gear can adjust the engine speed and compensate the engine torque by adopting double motors, which makes the fuel economy and emission performance of hybrid electric vehicle(HEV)significantly improved. However, the PHEP with single planetary gear can generate power cycling phenomenon frequently during driving, reducing the overall efficiency of the system. To further improve fuel economy, an optimization design scheme of PHEP configuration with single planetary gear is proposed in this paper. Firstly, the operating characteristic and the topology of output/input PHEP configuration are analyzed, the connection relationship of the two topologies is break up and recombined to generate the basic topology scheme. Secondly, all feasible topologies based on basic topology scheme are explored, and all feasible topologies are combined to generate a new configuration scheme. Finally, the global optimization control strategy based on dynamic programming(DP) algorithm is applied to simulate the best economy and the best dynamic performance of the proposed configuration scheme. The results demonstrate that the optimization design scheme of PHEP configuration with single planetary gear proposed in this paper can effectively improve the vehicle comprehensive operating performance.