Position servo control of a DC electromotor using a hybrid method based on model reference adaptive control (MRAC)

This paper dealed with position control problems of a DC motor servo system that had nonlinear friction and was subject to parametric uncertainties, external disturbances, etc.. In order to overcame those unfavourable factors mentioned above, a model reference adaptive control method was proposed to regulate the important and main speed loop in the positioning system which was designed with three closed control loop, where a compensatory measure was given so as to counterbalance the friction torque disturbances. In addition, the other two close loops were built in adjusting the position and the current of the servo system respectively that aimed to achieve the fast and precise positioning and increase dynamic stiffness against load disturbances. Experimental results illustrate satisfactory performances in steady state error, load capability, high rapidity and so on.