2025 Volume 38 Issue 7 Pages 146-154
This note addresses the conversion problem of a priori designed unstructured controllers to observer-structured controllers. Observer-structured controllers have been proposed as a structural extension of Luenberger observer-based controllers to accommodate linear parametric plant systems with unspecified nominal state-space matrices, and the usefulness has been demonstrated in the literature. However, the conversion process in the literature uses only the mathematical models of the plant systems and the a priori designed unstructured controllers, which might degrade the plant state estimation performance of the converted observer-structured controllers due to the possibility of unexpected disturbances, unmodeled dynamics, etc. of the practical operating environment. Therefore, a conversion method which well reflects the practical operating environment has been desired. To this end, this note proposes a conversion method, which is based on the least square method, by using the data of the plant systems controlled by the a priori designed unstructured controllers under practical operating environment, and illustrates the effectiveness of our method.