Moment matching for nonlinear differential-algebraic equations

The problem of model reduction by moment matching for nonlinear singular systems is considered. The notion of moment is extended to this class of systems by means of the center manifold theory. The characterization of the moments at infinity and of the moments for nonlinear parametric singular systems is discussed. The problem of model reduction for singular perturbation systems is analyzed. A family of singular reduced order models achieving moment matching is presented. Throughout the paper the results are illustrated by means of examples