Ph.D. Thesis

Ph.D. in international cotutelle: Universidad de Concepción, Chile - Université Claude Bernard Lyon 1, France,

May 2008 - March 2012

Supervisors:

Funding:

  • Chilean CONICYT scholarship.

Defended:

  • 9th March 2012, University Claude Bernard Lyon 1, Villeurbanne, France.

Jury:

  • Prof. Denis Dochain (Catholic University of Louvain, Belgium),
  • Prof. Arjan van der Schaft (University of Groningen, Netherlands),
  • Prof. Witold Respondek (INSA de Rouen, France),
  • Prof. Bernhard Maschke (University Claude Bernard Lyon 1, France),
  • Prof. Daniel Sbarbaro (University of Concepción, Chile).

Thesis title:

Control of irreversible thermodynamic processes using port-Hamiltonian systems defined on pseudo Poisson and contact structures.

Thesis Abstract:

This doctoral thesis presents results on the use of port Hamiltonian systems (PHS) and controlled contact systems for modelling and control of irreversible thermodynamic processes. Firstly, Irreversible PHS (IPHS) has been defined as a class of pseudo-port Hamiltonian system that expresses the first and second principle of Thermodynamics and encompasses models of heat exchangers and chemical reactors. These IPHS have been lifted to the complete Thermodynamic Phase Space endowed with a natural contact structure, thereby defining a class of controlled contact systems, i.e. nonlinear control systems defined by strict contact vector fields. Secondly, it has been shown that only a constant control preserves the canonical contact structure, hence a structure preserving feedback necessarily shapes the closed-loop contact form. The conditions for state feedbacks shaping the contact form have been characterized and have lead to the definition of input-output contact systems. Thirdly, it has been shown that strict contact vector fields are in general unstable at their zeros, hence the condition for the the stability in closed-loop has been characterized as stabilization on some closed-loop invariant Legendre submanifolds.

Keywords: Port Hamiltonian system, contact system, irreversible thermodynamics, nonlinear control.