(19)
(11)EP 2 685 095 A3

(12)EUROPEAN PATENT APPLICATION

(88)Date of publication A3:
28.06.2017 Bulletin 2017/26

(43)Date of publication A2:
15.01.2014 Bulletin 2014/03

(21)Application number: 13175311.3

(22)Date of filing:  05.07.2013
(51)Int. Cl.: 
F03D 7/02  (2006.01)
(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR
Designated Extension States:
BA ME

(30)Priority: 09.07.2012 DK 201270417

(71)Applicant: Envision Energy (Denmark) ApS
8600 Silkeborg (DK)

(72)Inventor:
  • Grabau, Peter
    6000 Kolding (DK)

(74)Representative: Tellefsen, Jens J. 
Patrade A/S Fredens Torv 3A
8000 Aarhus C
8000 Aarhus C (DK)

  


(54)Method and system to actively pitch to reduce extreme loads on wind turbine


(57) The present invention relates to a method of controlling an idling wind turbine in which wind condition data and wind turbine position data are collected by a sensor system, and a control system computes an optimal pitch angle for at least one rotor blade of the wind turbine, and where at least one pitching system continuously turns the rotor blades in the same direction in any multiples of 360 degrees. The present invention further relates to a wind turbine with a sensor system comprising at least one wind sensor configured to measure wind condition data in the vicinity and preferably up-wind of the wind turbine, and a control system comprising at least one computer with means for executing a control algorithm and configured to process sensor input from the sensor system and to compute an optimal pitch angle value for a rotor blade on the hub. This allows the rotor blade to be pitched into angle in which the mechanical loads of that rotor blade are reduced to a minimum, when the wind turbine is idling.