| 摘要 |
<p>The present invention comprises a wind turbine design where the preferred layout is a two bladed teetered downwind rotor with fixed pitch and with a smaller secondary rotor coupled to an electric generator mounted at the tip of each main rotor blade for extraction of the power of the main rotor as well as the power of the tip vortices of the main rotor. The functions of tip rotors are two-fold: They constitute the energy conversion system and the safety braking system. Coning of the main rotor in combination with the considerable weight at the blade tips is used to balance the wind loads and thus reducing the flapwise blade root moment. Speed control of the secondary rotors constitutes the main control of the wind turbine and they also act as a safe brake system as their thrust coefficient becomes high when they speed up at a power loss situation.</p> |
