Tianyu Ji and Noriyuki Hori
Digital Signal Processing, Digital Control, Ramp-Tracking, Plant-Input-Mapping
Digital redesign method called the Plant-Input-Mapping (PIM) method is used as bases for the design of a digital controller to track a ramp-type reference input without steady-state errors. This is achieved by modifying a lower order part of the numerator in the pre-filter so that the condition for the controller to have zero steady-state error is satisfied. The Euler operator is used so that the arguments made in the continuous-time domain are carried over to the discrete-time domain with ease. Simulation results are presented to show that the proposed modification made to the PIM digital controller is effective. Comparisons with the digital controller designed using the Tustin discretization method are also shown.