Electronic Control Of Continuously Variable Transmissions

this paper, we present an electronic control strategy for a mechanical CVT that consists of a wet multi-plate clutch and a pushbelt variator. Using a virtual engineering approach, the ultimate powertrain control problem (optimal shifting) is translated in a set of hierarchical control problems. To realize optimal shifting, the concept of variogram control is implemented by two PI-controllers. Next, the characteristics of the variator and the clutch are taken into account, by an explicit static feedforward. PI-controllers are added, to deal with modeling errors and uncertainty. Finally, the behavior of the electro-hydraulic actuator is optimized, by redesigning the valves and by adding actuator contro