THE PARTIAL MODEL-MATCHING OR PARTIAL DISTURBANCE REJECTION PROBLEM -GEOMETRIC AND STRUCTURAL SOLUTIONS

The Partial Model Matching Problem (or equivalently, the Partial Distu rbance Rejection Problem) is revisited here. It has been initially int roduced in [2] and amounts to matching the first kappa Markov paramete rs of the plant with those of the model. This obviously finds all its interest when no solution exists to the Exact Problem. We give both ge ometric and structural solutions to these problems. The geometric solu tion is in terms of the steps of the well known supremal output nullin g controlled invariant subspace algorithm. The structural conditions a mount to comparing some list of integers, namely some orders of zeros at infinity.