  The goal of this paper is the experimental validation of a gray-box
equivalent modeling approach applied to microgrids. The main objective of the
equivalent modeling is to represent the dynamic response of a microgrid with a
simplified model. The main contribution of this work is the experimental
validation of a two-step process, composed by the definition of a nonlinear
equivalent model with operational constraints, adapted to the microgrid
environment, and the identification procedure used to define the model
parameters. Once the parameters are identified, the simplified model is ready
to reproduce the microgrid behavior to voltage and frequency variations, in
terms of active and reactive power exchanges at the point of common coupling.
To validate the proposed approach, a set of experimental tests have been
carried out on a real LV microgrid considering different configurations,
including both grid-connected and islanded operating conditions. Results show
the effectiveness of the proposed technique and the applicability of the model
to perform dynamic simulations.
