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.

One of the main crises that the world will face is the over pollution of the environment due to the use of fossil fuels. This problem will be solved by replacing renewable energy sources (RESs). DC microgrids (DCMGs) provide the ability to exploit all the potential of RESs. But, high penetration of these sources reduces the inertia and damping of the DCMGs. Therefore, it makes DCMG vulnerable to fluctuations and disturbances. This challenge can be addressed by using distributed energy storage systems (DESS) in DCMGs and inertial simulations. To improve the inertia as well as to balance the charge/discharge of the DESS, the concept of a virtual supercapacitor based on the state of charge (SOC) is introduced. Under the proposed control strategy, DCMG inertia is provided and the SOC balance is maintained in charge and discharge mode. Due to the bidirectional power transmission capability, symmetrical structure and considering the protection purposes of dual half‐bridge converter (DHB) can be selected. A small signal has also been investigated to analyse the role of virtual inertia in stability. The simulation results in MATLAB/Simulink show the correct performance dynamics and high impact of the proposed scheme compared to conventional schemes.

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