On-line Identification of a Torque Converter Model

Most passenger cars on the road today employ planetary automatic transmissions, which use torque converters for vibration isolation and torque amplification at vehicle launch. Torque converter models have been used primarily for analysis and design, but have seen some use for on-line estimation and control. Since model parameters vary with operating conditions such as temperature as well as the condition of the transmission fluid, there is a need for on-line identification of these parameters for validity of the model across a wide range of operating conditions. In the current study, a novel method to update torque converter model parameters on-line is presented. Importantly, exponential convergence of the model parameter estimates to their respective true values is demonstrated. The proposed method is numerically validated for a vehicle under realistic driving conditions. The simulation results indicate that the proposed method is capable of on-line torque converter model identification under slowly varying operating conditions. (C) 2017, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.