The aim of this book is to provide insight into the development of an integrated modeling method for wind turbines using various software packages. A Wind Turbine (WT) can be regarded as a Wind Energy Conversion System (WECS) consisting of electrical, mechanical, aerodynamic, power electronic, and control components. Thus a full-scale model of a WT system should incorporate various phenomena such as electrical, mechanical, and aerodynamic effects, especially when the WT is connected to the grid. In this book, after a review of basic WT concepts and software tools, a simulation structure is proposed for studying WTs. It integrates the mechanical and electrical components of a WECS by utilizing commonly used software tools. Based on the simulation structure, a model for a three-bladed WT with a doubly-fed induction generator is developed that is used to investigate the impact of voltage sag on the wind turbine tower vibration. A similar simulation structure is used to model a two-bladed...