Variable

Wind turbine variable speed constant frequency system

For variable speed wind turbines, one of two types of generators can be used: a (doubly fed ) or an FRC (fully rated converter). A DFIG generator draws from the transmission system; this can increase the vulnerability of a transmission system in the event of a failure. A DFIG configuration will require the generator to be a wound rotor; squirrel cage rotors cannot be used for such a configuration. [PDF Version]