Robustness properties of the optimal regulator for systems with delays in the state are characterized. A Nyquist stability criterion is developed and the circle condition of the optimal regulator is derived. On the basis of these results, the stability margin of the optimal regulator is evaluated as by Lehtomaki et al. (1981), and it is shown that the stability margin is equal to that in the finite-dimensional case.
|ジャーナル||International Journal of Control|
|出版ステータス||Published - 1987 10|
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