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9. Tower
Seite 26
| Owners Manual SkyWind NG, Version 5.1
9.4 Structural stability
Due to the low size of the SkyWind NG the tower is not a part of the wind turbine as defined by
DIN EN 61400
-
2. This greatly reduces cost as SkyWind Energy can manufacture, sell and ship
the SkyWind NG without a mandatory tower system. The owner can use whichever tower is
suitable to the turbines requirements and is available locally. The patented two bladed rotor is
as tiny as 0.08 m² in area each
-
very much limiting its thrust forces. Still the forces under full
power operation in a storm can be substantial:
The wind turbines amount of torque to be withstood by the tower mounting is depending on
the tower height:
1 m:
250 Nm
2 m:
500 Nm
3 m:
750 Nm
5 m:
1.250 Nm
The thrust generated by the tower and its accessories have to be added to this value. This
forces would also greatly increase if the turbine is not shut
-
off by the storm control at the right
time. Always plan the tower with a proper safety margin.
Every structural analysis is required to
provide a safety factor of at least 3x times the max. load calculated for the system!
Keep in mind that the wind turbines operation must be stopped once 45 V DC operating voltage
(70 kph wind speed) is reached! Although the automatic storm control is very effective you can
extend your turbine opertional life by switching it off manually prior to a heavy storm.
SkyWind NG
Max. Thrust Force
:
250 N
Rotor Area Covered:
0,16 m²
Operating Frequency:
10
-
50 Hz
In regions where Hurricane (SSHS scale) force wind speeds (119+ kph) are possible
the rotor has to be dismounted before such an extreme wind event! Alternatively
the turbine can be mounted to a tiltable mast which is tilted prior to the hurricane.
