1995 Volume 8 Issue 3 Pages 106-114
In this paper invariant zeros of distributed parameter systems are analyzed. First it is shown that the invariant zeros of the systems are given by the inverse of the eigenvalues of certain bounded operators. Next in the case where sensors and actuators are collocated in some sense, simple useful conditions are given which assure that the systems (not necessarily stable) have no unstable invariant zeros. Several examples are presented to show the usefulness of the conditions.