Provided by: Iosrjournals
Date Added: May 2015
The type III control loops are advantageous as compared to type I and type II as, if frequency domain modeling of the control loop is followed; type-III control loops are characterized by the presence of three pure integrators in the open-loop transfer function. Therefore, such a control scheme has the advantage of tracking fast reference signals since it exhibits zero steady-state position, velocity and acceleration error. This advantage is considered critical in many industry applications, i.e., control of electrical motor drives and control of power converters, since it allows the output variable, i.e., current or speed, to track perfectly step, ramp and parabolic reference signals.