Robust Stabilization of First-Order Time-Delay Systems with Parametric Uncertainty

This contribution is focused on an approach to robust stabilization of continuous-time single-input single-output first-order time-delay systems with parametric uncertainty. The applied feedback controllers are obtained by means of an algebraic synthesis in the ring of proper and stable rational functions. Subsequent robust stability tests utilize the combination of plotting the value sets of a family of closed-loop characteristic quasi-polynomials with the zero exclusion condition. The illustrative examples cover three successive cases of plants with uncertain gain, uncertain time constant and uncertain time-delay term which are controlled using two differently tuned regulators. Key-Words: Robust Stabilization, Time-Delay Systems, Parametric Uncertainty, Value Set Concept, Zero Exclusion Condition