Weight optimization for maximizing robust performance in ℋ∞ loop-shaping design

Abstract This paper proposes a design framework that maximizes the robust performance of a closed-loop system via weight optimization in ℋ ∞ loop-shaping control. In line with design objectives, frequency-dependent optimization problems are formulated in LMI framework to maximize robust performance at low and high frequencies, and directly improve the robust stability margin at mid frequencies. The philosophy of the work thus gives the best robust performance that can be achieved on a particular problem once a level of robust stability margin is demanded. Loop-shaping weights and controller are simultaneously synthesized from the proposed algorithm.

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