Reliable and Robust Automated Synthesis of QFT Controller for Nonlinear Magnetic Levitation System Using Interval Constraint Satisfaction Techniques

  • P. S. V. NatarajEmail author
  • Mukesh D. Patil
Part of the Studies in Computational Intelligence book series (SCI, volume 539)


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 (realpaver) [1]. The method is guaranteed to find all feasible controllers of given structure in the search domain. The controller designed using proposed method is experimentally tested on ECP’s Magnetic Levitation system [2] which has open loop stable and unstable configurations.


Robust Control QFT Automatic Loop Shaping Constraint Propagation Interval Analysis ICSP 


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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  1. 1.Department of Systems and Control EngineeringIndian Institute of Technology, BombayMumbaiIndia

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