Inertia emulation with incorporating the concept of virtual compounded DC machine and bidirectional DC–DC converter for DC microgrid in islanded mode

Abstract

Abstract Independence in energy generation, attention to environmental issues, limited fossil fuel sources, and easy access to renewable energy sources have led governments, industry, and engineering to use renewable energy sources for decades. Meanwhile, microgrids for residential, commercial, industrial, and military purposes are widely used using these resources. However, the use of these sources in microgrids is associated with the challenges of uncertainty and lack of inertia. Therefore, by using energy storage systems in DC microgrids, the mentioned challenges can be overcome by emulating inertia. The purpose of this paper is to present a virtual compounded DC machine (VCDCM). The governing equations of the compounded DC machine have been accurately studied and the desired characteristics of this machine have been used to emulate inertia through the control of the buck‐boost converter connected to the energy storage systems in the concept of VCDCM. Proposed scheme; in an islanded microgrid with maximum components and standards required; Simulated in the Simulink/MATLAB environment. The results obtained under different scenarios confirm the ability of the proposed scheme to stabilize the DC bus voltage. The magnitude of DC bus voltage deviation from the reference value when an error occurs has resulted in a significant reduction compared to conventional schemes.

Keywords

• Power electronics, supply and supervisory circuits
• Distributed power generation
• Distribution networks
• DC‐DC power convertors
• Other energy storage