基于扩展状态观测器和滑模控制的双离合器自动变速器起步自适应控制

双离合器自动变速器（Dual Clutch Transmission，DCT）随着服役时间的增加离合器性态会发生变化导致起步性能下降，为降低离合器性态变化对起步性能的影响，提出一种基于扩展状态观测器和滑模控制的DCT起步自适应控制方法。首先，建立DCT起步动力学模型、发动机模型和液压控制系统模型；将DCT起步问题转化为参考轨迹跟踪问题，通过工况识别并利用极小值原理获得了不同起步工况的参考轨迹；在DCT起步动力学模型中将与离合器性态变化相关的项定义为不确定项，设计扩展状态观测器对不确定项进行估计，同时结合自适应滑模控制器，获得了起步发动机转矩和离合器油压的自适应控制率；为了跟踪发动机转矩和离合器油压的自适应控制率，设计了发动机转矩跟踪控制器，同时对液压系统采用了PID闭环控制；通过MATLAB/Simulink平台仿真以及台架试验验证所提出的DCT起步控制方法对离合器性态变化的自适应效果。研究结果表明：所提出的起步自适应控制方法能够有效避免由离合器性态变化导致的起步延时，同时1挡缓起步和急起步的仿真冲击分别减小了53.11%和43.42%，试验起步冲击分别减小了35.66%和30.31%。

Adaptive Starting Control of Dual Clutch Transmission Based on Extended State Observer and Sliding-mode Control

The performance of a dual clutch transmission (DCT) changes with the increase in service time, leading to a decrease in starting performance. To reduce the influence of clutch performance change on the starting performance, a DCT start adaptive control method based on an extended state observer and sliding-mode control is proposed. First, the DCT starting dynamics model, engine model, and hydraulic control system model are established. The DCT starting problem is transformed into a reference trajectory tracking problem, and the reference trajectories of different starting conditions are obtained through condition identification and a minimum principle. In the DCT starting dynamics model, the term related to the change of clutch performance is defined as the uncertainty term, and the extended state observer is designed to estimate the uncertainty term. At the same time, the adaptive control rate of the starting engine torque and clutch oil pressure is obtained utilizing the adaptive sliding-mode controller. To track the adaptive control rate of the engine torque and clutch oil pressure, an engine torque tracking controller is designed, and proportional-integral-derivative closed-loop control is adopted for the hydraulic system. The adaptive effect of the proposed DCT starting control method on clutch performance change was verified by MATLAB/Simulink platform simulation and a bench test. The results show that the proposed adaptive control method can effectively avoid the starting delay caused by the change in clutch performance. At the same time, the simulation impact of first-gear slow start and fast start is reduced by 53.11% and 43.42%, respectively, and the experimental starting impact is reduced by 35.66% and 30.31%, respectively.