COMPARISON OF MULTIPLE TIME-SCALE ANALYSIS AND OVERLAPPING DECOMPOSITION.

Two-level hierarchical systems are considered. A comparison of two different design methodologies, namely, multiple time-scale analysis and overlapping decompositions, is presented. The comparison is based on quadratic performance indices. It is demonstrated that the multiple time-scale approach, in general, produces better results whenever the time-scale parameter is small. However, the overlapping decompositions approach usually yields better controller designs as the time-scale parameter get larger. An example of a mass-spring system is presented to illustrate the practical application of the theory.