Modern smart grid should efficiently accommodate the renewable resources such as wind energy under different operation conditions. High level of wind energy penetration into SG results in operation constraints to avoid any tripping out of wind generators from the grid during fault conditions. Therefore, following the fault occurrence, the utility has to restore power as quickly as possible. This requires accurate and efficient fault location algorithms to have appropriate action for rabid service restoration. In modern power systems, wind energy shares significant amount in electricity generation. Accordingly, the grid performance could affected due to the natural behavior of the connected wind farms. The main challenge is to fulfill the voltage ride through (FRT) requirements and fast fault detection as well as reactive power coordination using FACTs devices such as STATCOM. This book presents fast and efficient over current and under voltage protections against faults on both grid high voltage line and on medium voltage feeders connecting the wind turbines to the point of common coupling