Modellbasierte Optimierung des Betriebsverhaltens eines Kegel-Ring-Getriebes in einem Kraftfahrzeug

  • Model based optimization of the driveability of a cone ring transmission in a vehicle

Papakonstantinou, Nikolaos; Gold, Peter Werner (Thesis advisor)

1. Aufl.. - Aachen : Mainz (2008)
Dissertation / PhD Thesis

Page(s)/Article-Nr.: VII, 126 S. : Ill., graph. Darst.

Aachen, Techn. Hochsch., Diss., 2007


This thesis describes the most important processes for the development of a Prototype Control System for vehicle application of the cone ring transmission. Based on a model of the cone ring transmission, it was possible to develop a closed loop control for the ratio adjustment, and also to test the driving strategies prior to the vehicle application. Enormous savings in development time are thus realized. It was possible to predict the driving behavior of the car, especially under dynamic situations, with the usage of this model. For these situations, filter and algorithms were developed for the safe functionality of the cone ring transmission. With the usage of the Rapid Prototype Platform of dSPACE and the model development in Matlab-Simulink, it was possible to implement the developed control algorithms and driving strategies in real time into a vehicle equipped with the cone ring transmission. The data evaluation from the vehicle test showed that the developed model can be used as a pre-calibration tool for vehicle application. Furthermore, this thesis demonstrates model based optimization of the ratio controls concerning the stability, the accuracy, and the response time. Due to the high bandwidth of the controller, the system is sensitive to signal disturbances, and a good sensor quality is demanded. A reduction of the Controller bandwidth without a loss in accuracy, stability, and response time can be achieved by a model based disturbances’ compensation. For this purpose, the model of the Drill torque in the contact area is used. Based on vehicle measurements and test rig data, it was possible to verify the drill torque calculation. This made it possible to simulate the ratio change under dynamic situations more precisely. Using a Drill-Torque-Map developed in the model, it was possible to integrate a feed-forward disturbances’ compensation into the control algorithms. As a result, a controller with reduced bandwidth can be used without a loss in the quality of the control. Additionally, using the model, intelligent control algorithms have been developed, reducing the number of necessary sensors in the cone ring transmission, and consequently also reducing the cost of the transmission. After the optimization of the ratio control, control algorithms for the clamping force have been designed. The clamping force control is possible through a constructive extension and a load relieving through a hydraulic medium. After testing the function of the load relieving, the algorithms of the automatic control of the clamping force during the driving operation have been programmed. The NEDC-Test Cycle measurements have shown that there is enough potential for further enhancement of the consumption of the cone ring transmission.