A new sliding mode control with disturbance observer for position control of DC servo motor is presented.
The conventional sliding mode controller changes the control law dependant on the state of switching surface and consequently, the control law is discontinuous and chatters at a theoretically infinite frequency.
To overcome this problem, the disturbance observer is used and compensates the effects of the parameter variations and the load disturbances. We can obtain the performance predetermined by the switching surface with continuous control law while the controlled system remains robust.
The performance of the proposed controller is compared with that of the conventional sliding mode controller through digital computer simulation and experiment.
