Discussion on: On Preserving Passivity in Sampled-data Linear Systems

The goal of this paper is to introduce a methodology to preserve the passivity of a continuous time system under discretization. The authors define a new output that allows to preserve the passivity of the continuous system in its discrete counterpart with the same sto-rage function. First the authors give a general definition of the output and then they specialize it for linear systems. The result proposed in the first part of the paper is very interesting and very general.