Variable wind turbine with power dissipation unit; method to operate a power dissipation unit in a wind turbine

摘要

A variable speed wind turbine (1) comprising: a generator (101); a power converter (102) for converting at least a portion of the electrical power generated by the generator (101), the power converter (102) comprising a generator side converter (110), a network side converter ( 111) and a DC link (direct current) (112) between them; a power dissipation unit (105) operatively coupled to the DC link (112); and a controller (120), in which the controller (120) is adapted to: receive a request to reduce the output power of the wind turbine (1); determine an anticipatory control power signal (PFF) from the difference between a reference generator power (Pgenerator) and a desired turbine power (Pred), including the reference generator power (Pgenerator) a power profile of gradual decrease of the generator (101), and including the desired turbine power (Pred) a desired gradual decrease power profile; and operating the power dissipation unit (105) based on the anticipatory control power signal (PFF) so that the output power of the wind turbine (1) is decreased at a desired speed.