Automated Synthesis of Fixed Structure QFT Controller Using Interval Constraint Satisfaction Techniques

Robust controller synthesis is of great practical interest and its automation is a key concern in control system design. Automatic controller synthesis is still a open problem. In this paper a new, efficient method has been proposed for automated synthesis of a fixed structure quantitative feedback theory (QFT) controller by solving QFT quadratic inequalities of robust stability and performance specifications. The controller synthesis problem is posed as interval constraint satisfying problem (ICSP) and solved with interval constraint solver. The method is guaranteed to find all feasible controllers of given structure in the search domain. The proposed method is tested on two benchmark problems, and simple, low order controllers are successfully obtained in quick time.