Using preaction with infinite or finite preview for perfect or almost perfect digital tracking

摘要

Perfect digital tracking is approached by using a dual-input controller which processes both the standard reference input and a suitable transient-correcting signal. The latter is generated by convolution of the reference with a pre-computed sequence depending on the controlled system dynamics. The proposed control theme can be used in both cases of infinite or finite (and possibly time-varying) preview time, and gives perfect or almost perfect tracking, respectively, also in the nonminimum-phase case.