Download Identification of Nonlinear Circuits as Port-Hamiltonian Systems This paper addresses identification of nonlinear circuits for
power-balanced virtual analog modeling and simulation. The proposed method combines a port-Hamiltonian system formulation
with kernel-based methods to retrieve model laws from measurements. This combination allows for the estimated model to retain
physical properties that are crucial for the accuracy of simulations,
while representing a variety of nonlinear behaviors. As an illustration, the method is used to identify a nonlinear passive peaking
EQ.
Download A Minimal Passive Model of the Operational Amplifier: Application to Sallen-Key Analog Filters This papers stems from the fact that, whereas there are passive models of transistors and tubes, a minimal passive model of the operational amplifier does not seem to exist. A new behavioural model is presented that is memoryless, fully described by its interaction ports, with a minimal number of equations, for which a passive power balance can be defined. The proposed model handles saturation, asymmetric power supply, and can be used with nonideal voltage references. To illustrate the model in audio applications, the non-inverting voltage amplifier and a saturating Sallen-Key lowpass filter are considered.
Download Fully-Implicit Algebro-Differential Parametrization of Circuits This paper is concerned with the conception of methods tailored
for the numerical simulation of power-balanced systems that are
well-posed but implicitly described. The motivation is threefold:
some electronic components (such as the ideal diode) can only
be implicitly described, arbitrary connection of components can
lead to implicit topological constraints, finally stable discretization
schemes also lead to implicit algebraic equations.
In this paper we start from the representation of circuits using a
power-balanced Kirchhoff-Dirac structure, electronic components
are described by a local state that is observed through a pair of
power-conjugated algebro-differential operators (V, I) to yield the
branch voltages and currents, the arc length is used to parametrize
switching and non-Lipschitz components, and a power balanced
functional time-discretization is proposed. Finally, the method is
illustrated on two simple but non-trivial examples.