Abstract
Power grids are rapidly evolving through digital transformation by adopting information and communication technologies. This evolution is creating concerns for electricity transmission and distribution companies to maintain security and reliability of the power grid. To safeguard the power grids, cyber-security risks and their consequences on security measures are required to be analyzed. This paper applies cyber-risk identification methodology with focus on digital substation for recognizing potential cyber-attacks, evaluates the cyber-risks and their impacts, and defines mitigation plans to ensure reliable operation of digital substations and safe and secure delivery of reliable power.