Choose the Best Wind Turbine Rotor System |
|
Rotor is the most important part of a . The rotor recives the kinetic energy from the wind stream and transforms it into mechanical shaft power. Components of a wind turbine rotor are blades, hub, shaft, bearings and other internals. Blades of the wind turbine have airfoil sections and through it is possible to design the rotor with a single blade, balancing of such rotors would be a real engineering challenge.Rotors with a single blade run faster and thus create undue vibration and noise. Further, such rotors are not visually acceptable.
Two bladed rotors also suffer from these problems of balancing and visual acceptability. Hence, almost all commercial designs have three bladed rotors. Some of the , used for battery charging, have more number of blades (four, five or six) as they are designed to be self starting even at low wind speeds. Size of the
rotor depends on the power rating of the turbine. The turbine cost, in terms of $ per rated kW, decreases with the increase in turbine size. Hence, MW sized designs are getting popular in the industry. Such turbines are installed already in Danemark( a 4.5 MW NEG Micon prototype).The rotor of this turbine is built with massive 54 m blades. Some manufacturers are planing even longer blades for their future projects.
Blades are fabricated with a variety of materials ranging from wood to carbon composites. Use of wood and metal are limited to small scale units. Most of the large scale commercial wind system are made with multi layered fiberglass blades.Attempts are being made to improve the blade behavior by varying the matrix of materials, reinforcement structures, ply terminations and manufacturing methods.Most of have up-wind rotors. During wind loading, the blades of these rotors may be pushed towards the tower. This reduces the effective blade length and thus the rotor area. This back bending may also cause fatigue to the blades in due course. To avoid this problem, modern rotors have prebend geometries. The pre-bend blades stretch to its total lengths under wind loading, and thus exploit the full potential of the rotor.
| Subscribe By Email / RSS >>> Get Free Updates >>> |
You might also like:
Tags: kinetic energy from the wind, modern rotors, modern wind turbines, multi layered fiberglass, small wind turbines, turbine cost, turbine size, Two bladed rotors, up-wind rotors, wind loading, wind power, Wind Powered, wind stream, wind turbine, wind turbine rotor