A study on sensorless control that considers the response of BLDC motor inside the oil hydraulic actuator for AWD clutch control

AWD (All Wheel Drive) clutch is a system that allocates the part of entire driving force with the front wheel drive shaft, among the main power delivered to the rear wheel axle through the electric control of clutch system inside the transfer module. It controls the surface pressure using the change (forward and reverse direction) in the oil flow rate of clutch pack depending on the driving condition, and delivers the driving force of main drive shaft to the sub-drive shaft through the difference of surface pressure. An oil hydraulic motor does not need maintenance and repair, and BLDC motor sensorless has been used as it is strong against outside influences such as vibration and heat. This paper proposed the control method of instantaneous forward and reverse direction considering response and stability.