This paper presents an analytical model for the simulation of traction drive dynamics and control in ratio change processes. The model systematically incorporates the formulations on the kinematics, dynamics and control characteristics of traction drives. In the model, the motion parameters of traction drive components are coupled to CVT inputs and outputs, torque losses, as well as ratio variations. The characteristics of a dual-feedback ratio control system are formulated in Laplace transform and integrated into the overall CVT system. The model is implemented in Matlab/Simulink block diagrams and is capable of predicting traction drive performances under various ratio change conditions. The effectiveness of the model is illustrated in a numerical example by the comparison between the simulation and experimental data on key CVT performance parameters.

Issue Section:
Technical Papers
Keywords:
automobiles, power transmission, traction, feedback, Laplace transforms, mechanical engineering computing, design engineering
Topics:
Dynamics (Mechanics), Rollers, Simulation, Traction, Control systems, Feedback, Modeling, Pistons
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Copyright © 2001
 by ASME
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