Double-Loop Control for Torque Tracking of Dry Clutch

Abstract

Torque tracking is an important control target of a dry clutch. At present, the torque tracking control method of a dry clutch generally uses the relationship between the clutch torque and release bearing position obtained via experiment to convert the torque tracking control of the clutch into the position tracking control of the release bearing. However, due to the nonlinearity and time-varying parameters of the dry clutch, it is difficult to obtain an accurate and fixed relationship between torque and position. At the same time, there are also the nonlinearity and interference problems in the position tracking control process. In order to solve the above problems, this paper takes the torque tracking control process of the dry clutch in a three-speed automatic mechanical transmission of an electric vehicle as an example and proposes a double-loop control controller including torque loop and position loop. Firstly, the drive system dynamic model of electric vehicles and clutch actuator dynamic models is established. Secondly, the torque loop controller is established with the adaptive feedforward-feedback control method. The time-varying parameters are adaptively adjusted with adaptive feedforward control to solve the problem of the time-varying relationship between torque and position. In addition, the feedback control loop is added to improve the robustness of the controller. Thirdly, the position loop controller is established with the backstepping-based active disturbance rejection control method to solve the nonlinear and disturbance problems of the position tracking control. In the end, the torque loop and position loop are cascaded to form a double-loop controller, and the torque tracking control simulations of the dry clutch are carried out. The simulation results show that the double-loop controller has good control performance, and the effectiveness of the controller has been preliminarily verified.

Optimal Torque Control of the Launching Process with AMT Clutch for Heavy-Duty Vehicles

“…Feng et al [14] propose a dual clutch transmission launching control strategy based on pseudo-spectral optimization and data-driven control to respond to time-varying launching intentions, reduce friction and jerk, and improve launching quality. To accurately control the torque of the vehicle, positional closed-loop control [15,16] is generally used via an actuator, or torque control can be used directly [17,18]. Guo et al [19] propose a combined pressure feedback controller based on a PID algorithm to control the clutch torque to follow a reference torque trajectory.…”

“…Ding et al [22] propose an observer-based adaptive dynamic sliding mode control strategy to overcome the clutch position external perturbations during tracking to improve clutch torque control accuracy. Differences in clutch system parameters, vehicle states, and road conditions all affect clutch launching torque control for vehicles equipped with AMT [17]. In the process of optimizing clutch launching torque, some researchers consider vehicle information and the external environment as disturbances and reduce their uncertainty by designing an optimization controller that improves clutch engagement performance [23].…”