Multiple robust H_∞ controller design using the nonsmooth optimization method

Abstract

SUMMARYThis paper proposes a systematic technique to design multiple robust H ∞ controllers. The proposed technique achieves a desired robust performance objective, which is impossible to achieve with a single robust controller, by dividing the uncertainty set into several subsets and by designing a robust controller to each subset. To achieve this goal with a small number of divisions of the uncertainty set, an optimization problem is formulated. Since the cost function of this optimization problem is not a smooth function, a numerical nonsmooth optimization algorithm is proposed to solve this problem. This method avoids the use of Lyapunov variables, and therefore it leads to a moderate size optimization problem. A numerical example shows that the proposed multiple robust control method can improve the closed-loop performance when a single robust controller cannot achieve satisfactory performance.

Smooth switching linear parameter‐varying control for hypersonic vehicles via a parameter set automatic partition method

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Double-loop robust tracking control for micro machine tools

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