A condition for full zero assignment in linear control systems

Not only 2
n
poles but also
n
zeros can be assigned in linear control systems when state estimation is used to effect the feedback. It is shown here that the equations for assigning these
n
zeros using this scheme are similar in structure to those found for pole assignment in the observer, but, in certain circumstances despite plant minimality, complete freedom in their selection is not available. Identification of these conditions and their interpretation as a requirement on controller minimality is presented with an illustrative example.