Search Results

For a new concept of a hybrid drive line developed at the Swiss Federal Institute of Technology (ETH), a torque pedal interpretation for the accelerator pedal is investigated. For this purpose, based on a simple nonlinear model of the drive line, a robust nonlinear controller is developed. The controller consists of a nonlinear feedforward controller supported by a nonlinear estimator and a simple linear feedback controller. The robust performance of the control system developed is confirmed by simulations.

In order to achieve maximum fuel efficiency, the SI engine of the new CVT-equipped hybrid car developed at the Swiss Federal Institute of Technology (ETH) is operated in a high power regime (such as highway driving at speeds above 120 km/h) with its throttle in its 100-percent open position. Whenever an engine power which exceeds 11 kWs is demanded, there exists an equilibrium point between the engine torque and the torque induced by the drag. Any regulation of the vehicle speed has to be performed by altering the gear ratio of the CVT. If any acceleration is required, it is necessary to increase the engine speed. This requires that the vehicle has to be slowed down for a certain short period of time. If this characteristic behaviour of the car (which is typical for a non-minimum-phase system) is not accepted by a driver who demands and expects immediate acceleration, it might lead to critical situations.