CVT轻度混合动力系统电动机和发动机联合工作模式下的系统效率优化

Optimization of System Efficiency for the Mild Hybrid Electric Vehicle with Continuously Variable Transmission under the Motor and Engine Combined Working Conditions

进行无级变速器(Continuously variable transmission,CVT)轻度混合动力电动汽车关键部件效率的试验数值建模,基于效率数值模型和系统的纵向动力学方程,分析推导出混合动力电动汽车驱动工况不同工作模式下的系统效率计算公式,得到了系统效率优化模型,利用序列二次规划算法对CVT轻度混合动力电动汽车驱动工况的系统效率进行优化计算,从而确定了驱动工况不同工作模式下的最佳电动机/发电机输出功率和最佳CVT速比,为驱动工况下CVT轻度混合动力汽车系统效率的提高和控制策略的优化提供了方法和依据。

The experimental numerical molel for the efficiency of key components of a mild hybrid electric vehicle with continuously variable transmission（CVT） is built. Based on the efficiency model and the longitudinal dynamics equations of the mild hybrid power system, the formulas for calculating the system efficiency under different driving conditions of hybrid electric vehicle are derived and the model for system efficiency optimization is obtained. The sequential quadratic programming （SQP） algorithm is applied to calculating the optimization of system efficiency of the mild hybrid electric vehicle under different driving conditions, so the electrical motor/generators power and the optimal CVT speed ratio under the different driving conditions. The research provides a method for optimizing the control strategy to improve the system efficiency of the CVT mild hybrid electric vehicle.