Design of $H_{\infty}$ Controller with Different Weighting Functions Using Convex Combination

  • Kim Min-Chan (KIMICS) ;
  • Park Seung-Kyu (KIMICS) ;
  • Kwak Gun-Pyong (KIMICS)
  • Published : 2004.03.01


In this paper, a combination problem of controllers which are the same type of $H_{\infty}$ controllers designed with different weighting functions. This approach can remove the difficulty in the selection of the weighting functions. As a sub-controller, the Youla type of $H_{\infty}$ controller is used. In the $H_{\infty}$ controller, Youla parameterization is used to minimize $H_{\infty}$ norm of mixed sensitivity function by using polynomial approach. Computer simulation results show the robustness improvement and the performance improvement.


Convex combination;Robust control;Youla parameterization


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