Study of DOUBLY-FED Induction Generator For Variable Speed Wind Energy Conversion Systems

In recent years, wind energy has become one of the most important and promising sources of renewable energy, which demands additional transmission capacity and better means of maintaining system reliability. The evolution of technology related to wind systems industry leaded to the development of a generation of variable speed wind turbines that present many advantages compared to the fixed speed wind turbines. For example, grid codes are being revised to ensure that wind turbines would contribute to the control of voltage and frequency and also to stay connected to the host network following a disturbance. In response to the new grid code requirements, several DFIG models have been suggested recently. This paper deals with the introduction of DFIG and AC/DC/AC converter control