功率分流式混合动力车辆发动机起动过程优化的仿真研究

Simulation of Engine Start Process Optimization of Power-Split Hybrid Electric Vehicles

利用GT-SUITE软件建立了基于详细机理的发动机模型,用MATLAB/Simulink建立了三相永磁同步电机数学模型及其弱磁控制系统。通过解决跨平台转矩传递及步长协调等问题,建立二者耦合的混合动力车辆瞬态仿真平台。研究了发动机初始喷油转速对起动过程整车能耗、起动时间和平顺性的影响,分析了整车需求功率与经济性初始喷油转速的关系。研究结果表明:发动机倒拖至800 r/min以上开始喷油可以缩短起动时间;冲击度与发动机转矩建立时间呈负相关关系;发动机倒拖起动时最低综合能耗所对应的初始喷油转速与起动时被分配到的需求功率成正比,与固定800 r/min开始喷油的策略相比能耗可降低20%~31%。

A detailed engine model based on detailed mechanism was built by GT-SUITE.A mathematical model of three-phase permanent magnet synchronous motor(PMSM)and its magnetic weakening control system were built by MATLAB/Simulink.By solving cross-platform torque transfer and step coordination problems,a hybrid electric vehicle(HEV)transient simulation platform coupled with the two sides was established.The influence of engine initial fuel injection speeds on the energy consumption,starting time and ride comfort during starting process was studied,and the relationship between vehicle demand power and economic initial fuel injection speed was summarized.The results show that the starting time can be reduced when the engine is towed backward above 800 r/min to start injection.There is a negative correlation between the jerk and the establishment time of engine torque.The minimum comprehensive energy consumption corresponding to the initial fuel injection speed is proportional to the required power during starting.The energy consumption can be reduced by 20%~31% compared with the fixed initial injection of 800 r/min.