Pointwise Criterion for Controller Robustness

摘要

A pointwise criterion for controller robustness with respect to stability ispresented. The term 'point' here refers to complex frequency in the right half plane. The proposed test is based on the concept of the minimal angle between subspaces determined by the plant and the compensator. The test leads to separate balls of uncertainty at each frequency, and may therefore help to reduce conservativeness in the analysis of robustness.