History of the former windenergy converter

The Grosse Windkraftanlage, (this means huge windenergy converter) "GROWIAN"
was earlier worldwide the largest windenergy converter.

Technical data:

Power output data:
Elektric rated power 3000kW, spezific output 380 Watt per squaremeter,
windvelocity at hub: start- 5,4 m/s, rated- 12,0 m/s, shut off- 24 m/s, max. survival- 60,0 m/s.
Energy output/annum at 9,3 m/s windvelocity, roughly 12 GWh.
Number of rotorblades 2, diameter 100,4 meter, rpm 18,5 at operating point. Rotor turns leewards, tip speed ratio 8 at rated windvelocity ,
airfoilsection chordline at bladetip 1,3 meter, depth at root 4,93 meter, wash out (blade twist) 18 Grad (not linear), area rotorblade (each) 105 squaremeter, taper 0,26 , aspect ratio 15,4
airfoil section at radiusposition R=0,3 FX-77-W343, at R=0,6 FX-77-W-258,
at R=1,0 FX-79-W-151.
Blademass 23 tons each.
Material of rotorblades: inner steel beam with outer glassfiber reinforced shell, pitch control mechanic-elektric, hubconstruction as pendulum hub (halfcardanic).
conctruction: 2 planetary-steps, 1 spur-wheel-step, gear ratio total 1:81.
Machinery house: Construction: steel-shell. Winddirection control, automatic, with small electric motor.
Mass machinery house, incl. rotor, 375 tons
Construction: steel cylindrical, single-acting rigging, height of tower 100 meter, mass 350 tons
Control mechanism:
Prinziple: combined rotational speed/power control via pitch control (actual blade angle) and direct acting inverter.
Construction: asynchronous, doubel-feded, nominal output 3443kVA at operating point (18,5 rpm). Nominal-cos-phi: asynchron 0,88 , with inverter 0,95 , rated voltage 6,3 kV, number of revolutions 1500 U/min.,
frequency 50 Hz, type of construction: D5 with 10 degrees line-shaft inclination.

Sectional view of machinery house and halfcardanic pendulum hub, GROWIAN

The GROWIAN-output-characteristica was calculated with the Hütter-theory at the IFB. The following diagrams show the "hilly terrain" of the powercoefficient (cP), plotted against the tip speed ratio (lambda). Parameter is the blade angle of adjustment(angle Theta) for the whole blade. Since 24th of mars 1997