液力自动变速器换挡控制轨迹优化方法

Control Trajectory Optimization Method of Automatic Transmission Gear-shift

随着液力自动变速器挡位数不断增加,出现了换挡过程中需要多个离合器协同操纵的多切换式换挡方式,使得换挡品质控制问题变得更加复杂。为同时满足自动变速器在传统单切换以及多切换式换挡中的换挡品质需求,建立了包含发动机动态模型、液力变矩器动态模型、行星变速器、离合器和车辆负载的车辆换挡过程动力学模型,并通过非道路车辆的实车试验结果对所建动力传动系统仿真模型进行了验证。结合换挡品质客观评价指标,利用hp自适应Legendre-Gauss-Radau正交配点法,对车辆换挡过程中的离合器/制动器油压轨迹进行了优化。建立换挡品质控制硬件在环实验平台,开展了变速器在多切换以及单切换式换挡过程控制实验。结果表明,换挡品质优化方法能够有效提高车辆在各换挡过程中的换挡品质。

Multi-transition gear-shift,which needs more than one pair of clutches to be controlled properly,is carried out along with the increasing development of gear number.The shift quality control of multiple transition gear-shift is a more challenging problem compared with the traditional single transition gear-shift process.To achieve a satisfying shift quality during both single and multi-transition gear shift,a dynamic model of automatic transmission containing engine,hydraulic torque converter,planetary gearbox,clutch and load of the vehicle is established.The experimental data of a test vehicle is used to verify the proposed dynamic model of the powertrain.The trajectory of clutch pressure during gearshift is optimized using hp-Legendre-Gauss-Radau method with the objective evaluation index.The test on a hardware in the loop(Hil)test bench is carried out,which can prove the proposed shift quality optimization method is effective to improve the shift quality during both traditional single transition gear shift and multi-transition gear-shift.