06.11.2024 - 4 pm (CET) - Dorothée Normand-Cyrot (Laboratoire des Signaux et Systèmes, Paris)

Title: About a class of discrete-time and sampled-data Hamiltonian structures

Abstract: Port-Hamiltonian structures have a pervasive impact in numerous applied domains enlarging the more traditional mechanical one. While these structures are unequivocally characterized in the continuous-time domain, several descriptions are proposed in the literature when referring to discrete-time or sampled dynamics. In this talk we discuss a description of port-Hamiltonian structures in discrete time that makes reference to the notion of average passivity, introduced to deal with systems without throughput. Exploiting the average passivity property of these forms, we show how damping feedback and energy-based control strategies can be designed. Then, we investigate the sampled-data case and show how these forms set in discrete-time can be recovered under time-integration through modification of the interconnection and dissipation matrices characterizing the continuous-time dynamics. Some simulations are presented to illustrate analysis and control performances.

04.12.2024 - 4 pm (CET) - Timo Reis (TU Ilmenau) 

Title: Energy-Optimal Control for infinite-dimensional port-Hamiltonian Systems

Abstract: We first present a theory for the optimal control of infinite-dimensional systems described by system nodes. In this context, we focus on minimizing the L^2-norm of the output, combined with an additional weighting of the final state. The input is assumed to lie within a closed and convex set. Next, we address energy-optimal control for infinite-dimensional port-Hamiltonian systems. We show that minimizing the supplied energy can be reformulated as an equivalent output minimization problem. The theory will be illustrated using a boundary control wave equation on a two-dimensional spatial domain.

08.01.2025 - 4 pm (CET) - Claudia Totzeck (BU Wuppertal)