Improvement of smart grid reliability considering various cyber network topologies and direct interdependency

The modern smart grid consists of two noticeable and intricate networks, cyber and power. Cyber networks have been employed for controlling, monitoring and protecting different types of physical systems. Nowadays, it is absolutely impossible to have an efficient and reliable operation of power networks without cyber networks. In the conventional methods, it is assumed that the cyber components are failure free. This simplification makes some errors for reliability assessment; specifically in smart grids with advanced cyber network topologies. This paper introduces a novel analytical reliability assessment method which can effectively consider the impact of direct cyber network failures on power networks. The proposed method evaluates the smart grid reliability taking into account both power and cyber (monitoring/control/protection devices) elements failures. In this paper, a new procedure based on the change of structure of cyber topology is proposed. An optimized cyber network structure is obtained to improve the reliability of smart grid. The test results indicate that there is a vital need to consider cyber negative effects as well as power effects on power grid for reliability assessment of smart grid.