  The Digital Twins offer promising solutions for smart grid challenges related
to the optimal operation, management, and control of energy assets, for safe
and reliable distribution of energy. These challenges are more pressing
nowadays than ever due to the large-scale adoption of distributed renewable
resources at the edge of the grid. The digital twins are leveraging
technologies such as the Internet of Things, big data analytics, machine
learning, and cloud computing, to analyze data from different energy sensors,
view and verify the status of physical energy assets and extract useful
information to predict and optimize the assets performance. In this paper, we
will provide an overview of the Digital Twins application domains in the smart
grid while analyzing existing the state of the art literature. We have focused
on the following application domains: energy asset modeling, fault and security
diagnosis, operational optimization, and business models. Most of the relevant
literature approaches found are published in the last three years showing that
the domain of Digital Twins application in smart grid is hot and gradually
developing. Anyway, there is no unified view on the Digital Twins
implementation and integration with energy management processes, thus, much
work still needs to be done to understand and automatize the smart grid
management.
