Publications

On compensation of nonminimum-phase zeros

Ulf Holmberg, Piotr Myszkorowski, Yves Piguet and Roland Longchamp. Automatica, 31(10):1433-1441, Septembre 1995.

Abstract

Nonminimum-phase (NMP) zeros may cause severe transients, like undershoots and oscillations, in a step response. The discrete-time case is studied in which a design of a set-point feedforward by placement of additional zeros is proposed. Optimal placements of zeros are given that minimize the maximal undershoot when the system has one real NMP zero. A system having two complex NMP zeros can be compensated such that a monotonic response is guaranteed, even in presence of model uncertainty.