The Empact CVT: modelling, simulation and experiments

This paper shows the implementation of a simulation model for new electromechanically actuated metal V-belt type Continuously Variable Transmission (CVT), referred to as the Empact CVT. An analysis of the dynamics of the actuation system and of the driveline shows that the eigenfrequencies of the system depend on both the CVT ratio and the slip in the variator. An accurate variator model is required to incorporate all characteristic dynamics. The implemented variator model is an explicit formulation of a model which gives an estimation of the tension forces and compression forces in the pushbelt. The simulation model also includes slip, shifting losses based on transient variator models and friction. Simulations are compared to measurements, showing good results.