Robust Regional Stability: Sufficient and Necessary Conditions

This paper focuses on the regional pole placement problem. The feasibility problem is derived to guarantee the closed loop system D-stable and robustly D-stable using full block S-procedure so that pole place constraints could be directly added to other control objectives. The sufficient and necessary condition is proved in the sense of limit, so the conservatism is avoided theoretically. The "uncertain" part of controller varies with system uncertainty, so the limitation on system uncertainty is released theoretically.