Performance of a city bus equipped with a Toroidal Traction Drive

In the paper, a comparison of performances of a city bus when equipped with the traditional automatic driveline consisted of a torque converter followed by epicyclic gear trains and when equipped with a Double Cavity Half Toroidal CVT is carried out. A simulation model is developed for evaluating fuel consumptions of the bus when a certain velocity cycle is followed. In particular, results of the comparison are evaluated referring to the ECE15 urban cycle. The model is built considering the hypothesis that the controlling system of the CVT is designed for obtaining in each situation the speed ratio that minimizes the specific fuel consumption and, hence, that allows the engine operation at the best efficiency value.