Summary: | 碩士 === 國立臺灣大學 === 機械工程學研究所 === 104 === The dual continuously variable transmission(DCVT), which investigated in this study, is assembled by two CVTs. At the primary pulley side, two CVTs are connected by one straight shaft and share the same rotation speed. However, two CVTs transmit power to two wheels independently. Although the DCVT system proposed in this paper is similar to the “Variomatic” system, which was developed by the Dutch car manufacturer DAF more than 50 years ago. With the advanced active CVT control widely used in modern car industry, the DCVT system may be able to achieve better fuel economy than the mechanical controlled Variomatic system. In addition, the active yaw moment control also becomes available to the DCVT system with active CVT control now to improve the driving safety and the vehicle performance. In this study, the dynamic models of the ADCVT system and other conventional differential system including solid-axle, open-differential are built. Split-mu test and J-turn test under different parameter including speed, steer angle, ADCVT gain and ratio-changing speed are carried out to simulate and compare the basic system characteristics of these systems. The simulation results show that the ADCVT system possesses limit-slip function to prevent loss of traction while one driving tire slips. And with proper system control, the system is proved to be able to improve the handling performance of vehicle.
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