Non-linear, hybrid terminal behavioral modeling of a dc-based nanogrid system

Abstract

This paper addresses the two-port network behavioral modeling of the power converters for renewable energy sources that feature non-linear static behavior. Based on the Hammerstein's approach, two models, non-linear dc and linear ac are both run simultaneously in the simulation while the dynamic model is constantly being updated with the operating point values from the static model, in order to include non-linear static behavior. The goal here is to develop a procedure for the terminal identification, so-called black-box modeling approach when engineers do not have an access to the internal structure, control and dynamics of the converters, but through appropriate measurements can extract needed information useful later for the system level simulations and stability analysis. The hybrid models of the source, interface and load converters have been shown in this paper, as well as the system-level verification with an average model. Index Terms-nanogrid system, behavioral model, nonlinear model, electronic power converters.

Blackbox Large-Signal Modeling of Grid-Connected DC-AC Electronic Power Converters

“…This is a block-based approach which includes nonlinear static functions that set the static operating point of the converter and linear dynamic blocks that account for the transient behavior. This strategy can be implemented with linear networks as in [14], or with a G-parameters structure, where the operating point is variable and dependent on the values of the input variables as in [36]. It should be noticed that with this approach the steady-state of the transfer functions should be unitary, as this value is set by the static nonlinear blocks.…”

Design and Implementation of Energy Management System With Fuzzy Control for DC Microgrid Systems

“…Additionally, low voltage (24V) ceiling-grid applications, especially for lighting, were also developed [15]- [19]. There are several research groups [20]- [33] which have extended the high voltage (380V) DC-distribution system to drive home appliances, of which the elegant power application research center (EPARC) has built a demonstration house for testing the overall system operation. In this paper, the system configuration including green power generator, energy storage element, DC appliance and equipment, and energy management system (EMS) with a fuzzy controller will be introduced.…”

The performance of polytopic models in smart DC microgrids

“…From a blackbox perspective, the Wiener-Hammerstein model has been proposed for this purpose. It is comprised of three blocks: one represents the nonlinear static behavior of the converter and the other two represent the dynamic of the input and the output by means of linear models [4], [5]. For converters showing significant dynamic nonlinearities, the polytopic model has been proposed.…”