Slip Control of Automatic Transmission Based on Discrete time Sliding Mode Controller

Abstract:

A discretetime sliding mode controller is designed to adjust the slip of torque converter lockup clutch so as to improve vehicle fuel economy and avoid the vibration of vehicle transmission system which is caused by engine torque fluctuation.Control variable is filtered by Filtfilt filter to smoothen vibration phenomenon of sliding mode control system.The simulation model of transmission system is built to verify this control method and to compare with the traditional proportionalintegralderivative (PID) control.For further testing the influence of slip control on vehicle fuel consumption in economic commission for Europe (ECE) cycle condition,actual transmission control unit (TCU) is involved in the hardwareintheloop experiments.The results of the simulation and experiment show that the slip control effectively absorbs transmission system shock and its transmission efficiency is far better than the torque converter working condition,so it can reduce the fuel consumption.In addition,the discretetime sliding controller with filter has a better response speed and trace command signal ability with control law changes smoothly.