Prof. Arjan van der Schaft gave a talk on July 11th, 2022 in our group about “Energy conversion in multi-physics systems” 

Biography (简介)

Prof. Arjan van der Schaft (IEEE Fellow, IFAC Fellow) received the undergraduate (1976, 1979) and PhD (1983) degrees in mathematics from the University of Groningen, the Netherlands. In 1982 he joined the Department of Applied Mathematics, University of Twente. In 2005 he returned to his Alma Mater as professor in Mathematics. Arjan van der Schaft was the 2013 recipient of the 3- yearly awarded Certificate of Excellent Achievements of the IFAC Technical Committee on Nonlinear Systems. He was Invited Speaker at the International Congress of Mathematicians, Madrid, 2006. Books authored by him include Variational and Hamiltonian Control Systems (1987, with P.E. Crouch), Nonlinear Dynamical Control Systems (1990, 2016, with H. Nijmeijer), L2-Gain and Passivity Techniques in Nonlinear Control (1996, 2000, 2017), An Introduction to Hybrid Dynamical Systems (2000, with J.M. Schumacher), and Port- Hamiltonian Systems: An Introductory Overview (2014, with D. Jeltsema).

Abstract

Consider a general physical system with two Arjan van der Schaft power ports: how to transfer energy from one port to the other? This problem is present in many technological applications, from the classical steam engine (how to convert heat into mechanical work) to motors, generators, fuel cells, and energy harvesting. Can we set up a general theory that is delineating the possible limitations in energy transfer, and guides us towards the most efficient (optimal?) control strategies? In this talk I will present some partial answers (which naturally lead to further questions), based on the port- Hamiltonian formulation of physical systems. In particular, I will show how the ‘isothermals’ and ‘adiabatics’ in the classical Carnot cycle for heat engines can be directly generalized to port-Hamiltonian systems endowed with a specific form of internal interconnection structure (such as shared by thermodynamic systems). The talk will be illustrated by a series of characteristic examples; from the gas-piston- damper system of thermodynamics to synchronous generators, DC motors and electromechanical actuators.