m Delkhosh - Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
m SaadatFoumani - Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran

In the present study, the aim is to optimize full and half-toroidal continuously variable transmission (CVT) in order to minimize the vehicle fuel consumption (FC) in ECE driving cycle. First, a model forboth toroidal CVT efficiency is presented. A simulation model of the considered power train isdescribed. The control strategy of CVT speed ratio based on minimizing the vehicle FC is introduced, and the algorithm of calculating the vehicle FC is shown. Afterwards, both types of CVT are optimized using Particle Swarm Optimization method (PSO) with the aim of minimizing the vehicle FC in ECEdriving cycle, and the optimized geometries are achieved. It is found that a remarkable fuel economy can be achieved through optimization of each type. The effects of the vehicle weight on the optimized geometries are examined. It will be shown that, the optimized geometry of full-toroidal type is notstrongly influenced by the vehicle weight, while the optimized geometry of half-toroidal one varies through variation of the vehicle weight.

Continuously Variable Transmission,Toroidal CVT,Fuel Consumption,Optimization,Vehicle Weight