Large-signal stability analysis of passivity-based droop control of islanded microgrids

• Published in: Energy reports 2024-12, Vol.12, p.2097-2107
• Main Authors: Ortega-Velázquez, Isaac, Avila-Becerril, Sofía, Espinosa-Pérez, Gerardo
• Format: Article
• Language: English
• Subjects: Droop control; Large-signal stability; Microgrids; Passivity–based control
• ISSN: 2352-4847; 2352-4847
• DOI: 10.1016/j.egyr.2024.08.010

In this paper, the large-signal stability properties of a system formed of a single-phase AC Microgrid equipped with a two-level control scheme are analyzed. The aim is to show that it is possible to formally characterize the operative capacities of the controlled system when the nonlinear model that describes its dynamical behavior is considered. Thus, the presented analysis contributes to the formulation of the widely demanded methodology to analyze the large-signal stability properties of Microgrids without invoking small-signal arguments. The analyzed model includes the dynamic of the power converters associated with each distributed energy resource, an inner control law, and a power-sharing mechanism. To better illustrate the scope of the contribution, it is assumed that the Microgrid operates in islanded mode. The inner control schemes are designed using passivity-based ideas, while the power-sharing stage includes the most popular and exhaustively implemented Droop control. The large-signal stability analysis of the Microgrid is carried out by exploiting the Port-controlled Hamiltonian structure of the network and taking advantage of the stability and passivity properties of this class of dynamical systems together with the Input-to-State stability properties of the Droop scheme. •A Large-signal stability analysis of the nonlinear model of a single-phase AC Microgrids is developed.•The nonlinear network model explicitly includes the dynamic behavior of the power converters.•Power balance and generation of grid-forming and grid-following nodes are achieved.•The inner control loop is developed using Passivity-based Control ideas.•The power-sharing mechanism corresponds to the widely implemented Droop control.