Abstract
This paper presents a newly developed steel-belt CVT that adopts a direct pulley pressure control system for speed ratio control. Because the mechanical system has been simplified compared with existing CVTs, the control system must be able to control the speed ratio with high accuracy. In addition, both good response and high robustness are increasingly required today in the speed ratio control design. Therefore, sliding mode control is employed to obtain excellent shift performance with high levels of response and robustness.
KEYWORDS – continuously variable transmission, ratio control, sliding mode control, CVT, tracking