P2混合动力汽车发动机起动过程变速箱控制策略研究

Research on Clutch Control Strategy of P2 Hybrid Electric Vehicle Engine during Starting Process

为实现P2混合动力汽车发动机起动过程整车驾驶的平顺性,对发动机起动过程变速箱的转矩预控控制策略进行了研究,针对现有控制策略在实车验证中存在的不足,提出了一种新的变速箱转矩预控控制策略。通过设计变速箱控制时的电机转速与DCT变速箱输入轴之间转速差的判断条件,避免了起动过程因转速波动而引起的整车顿挫,同时变速箱转矩控制过程中采取了加权转矩控制策略。最后通过Simulink建模,生成代码下载到变速箱控制单元中进行实车相关测试验证。验证的结果表明,所提出的变速箱的控制策略可有效地避免P2混合动力汽车发动机起动过程的冲击,实现了发动机起动过程变速箱控制的平稳过渡,可明显提升P2车辆驾驶的平顺性和舒适性。

In order to achieve the smooth driving of P2 hybrid electric vehicle for the engine starting, this paper studies the clutch control strategy during engine starting. Addressing the shortcomings of existing control strategies, a new clutch torque pre control strategy is proposed. By designing the judging condition of the speed difference between the motor speed and the input shaft of DCT gearbox, the vehicle’s jerk caused by the speed fluctuation in the starting process is avoided, and the weighted torque control strategy is adopted in the torque control process of gearbox. Finally, the generated code is downloaded to the transmission control unit for real vehicle related test verification by Simulink modeling. The results of validation test on real vehicle show that the proposed clutch control strategy can effectively avoid the impact of P2 hybrid vehicle engine starting process, the smooth transition of clutch control can be realized during engine starting process, the smoothness and comfort of vehicle driving can be ensured.