Design and Development on Lowlevel Drive System of Automotive Continuously Variable Transmission

Abstract:

A lowlevel drive system (LDS) of continuously variable transmission (CVT) which is used to drive stepper motor and highspeed digital onoff valves is developed.The lowlevel drive principle and electronic elements used in the system are given.Drive circuits and controller area network (CAN) protocol between gearbox interface unit (GIU) and engine management system are given.Hardwareintheloop simulation is operated,finally stepper motor and highspeed digital onoff valves succeed to be driven.Ratio control,clamping force control and clutch control are achieved rapidly and accurately,and the lowlevel drive system is validated.

Key words:continuously variable transmission; lowlevel drive system; gearbox interface unit; controller area network protocol; hardwareintheloop simulation