Optimize Ratio Control Strategy of CVT for Non-steady Working Condition

The vehicles in non-steady working condition often suffer the trade-off between power performance and fuel economy and also the lack of accurate ratio control target in the control strategy. With the analysis of power performance and economic performance and a driveline model with MATLAB/Simulink based on experiment data, the optimum matching datasheet control strategy is proposed. The relationship both fuel consume and the transmission ratio is first obtained through a large numbers of simulations. Then using the results matched with the required power performance a fitting curve is derived and determined the ratio control target. In the simulation of vehicles with CVT in ramp-driving conditions we demonstrated that the best fitting curve can give the accurate control of transmission ratio so that both good power performance and fuel economy is achieved.