Abstract: Smart grid is regarded as the next generation power grid, which provides bi- directional flow electricity and information, with improving the power grid reliability, security, and efficiency of electrical system from generation to transmission and to distribution. This reviews on the current state of technology in physical protection and also focuses on the system reliability analysis and failure in protection mechanism and its connection with renewability and micro grid.

Keywords: smart grid, physical protection, system reliability analysis, renewability mechanism and micro grid.