**1. Introduction**

Wind energy is playing a critical role in the establishment of an environmentally sustainable low carbon economy. This chapter presents an overview of wind turbine generator technolo‐ gies and compares their advantages and drawbacks used for wind energy utilization. Tradi‐ tionally, DC machines, synchronous machines and squirrel-cage induction machines have been used for small scale power generation. For medium and large wind turbines (WTs), the doubly-fed induction generator (DFIG) is currently the dominant technology while permanentmagnet (PM), switched reluctance (SR) and high temperature superconducting (HTS) gener‐ ators are all extensively researched and developed over the years. In this chapter, the topologies and features of these machines are discussed with special attention given to their practical considerations involved in the design, control and operation. It is hoped that this chapter provides quick reference guidelines for developing wind turbine generation systems.
