Modelling and control of an electro-mechanically actuated pushbelt type continuously variable transmission

For analysis, control design and testing of an electro-mechanically actuated CVT, a simulation model is built. The model incorporates all major driveline components and the proposed actuation system with servo motor actuation. The clamping forces in the variator are calculated using an explicit formulation of a model based on Coulomb friction. Identification of the non-linear model using step response analysis shows resonances between 8-12 [Hz] and between 20-30 [Hz], depending on the ratio. Closed loop bandwidths that can be achieved are typically 5 [Hz] for ratio control and 20 [Hz] for slip control