Document Type : Review Paper


1 Electrical Engineering,

2 University of Kerbala Electrical and Electronic Engineering Dept

3 Department of Electrical Engineering, University of Technology- Baghdad, Iraq,


Renewable energy sources (RESs), such as solar and wind power, offer new technologies for meeting the world's energy requirements. The distributed generator (DG) based on RESs has no rotational mass and damping effects compared to the traditional power system with synchronous generators (SG). However, the increasing penetration level of DG based on RESs causes low inertia, a dampening effect on the dynamic performance of the grid, and stability. A solution to improve the frequency stability of such a system is to provide virtual inertia by using virtual synchronous generators (VSG), which can be created by using short-term energy storage and a power inverter, and a suitable control mechanism. The VSG control mimics the dynamics of the rotation SG and enhances the power system's stability. This paper presents an overview of various topologies on virtual inertia, VSG concepts, control techniques, and VSG applications. Finally, the VSG challenges and future research will be discussed.

Graphical Abstract


  • RESs connected with the inverter have no physical inertia compared with the synchronous generator.
  • VSG provides the required inertia under sudden disturbances in a microgrid.
  • VSG controller emulates droop controller to decrease the frequency deviation.


Main Subjects

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