Abstract
It has often been believed that inH ∞-optimal synthesis methods, the resulting controllers have order much greater than the order of the plant. Recently, Limebeer and Hung [9] have shown that inH ∞-optimal synthesis problems of the “first kind” both optimal as well as suboptimal controllers have order which is no greater than the order of the plant. However, those authors do not provide any explicit algorithm for computing these controllers. In this paper we derive an explicit procedure for computing suboptimal controllers in problems of the first kind. These controllers have order no greater than the order of the plant and can be computed by solving only two Riccati and two Lyapunov equations.
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This research was supported by the National Science Foundation under Grant No. ECS-8810-578.
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Verma, M.S., Romig, J.C. Reduced-order controllers inH ∞-Optimal synthesis methods of the first kind. Math. Systems Theory 22, 109–148 (1989). https://doi.org/10.1007/BF02088294
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DOI: https://doi.org/10.1007/BF02088294