Copper is a vital metal in making wind power possible. The outdoor environment places great demand on cables, connectors, and generator windings used for wind power installations, especially for those situated offshore.
Copper provides the conductivity, corrosion resistance, strength and flexibility to meet all the demands of harsh conditions, where servicing and repair are very expensive.
Copper is used in:
- generator windings
- power cables
- earthing and lightning protection
- control systems
It could be said that all electricity and the modern world that it powers is created using one phenomenon: when a magnet moves near a coil of wire, an electric current will flow in the wire.
This is a generator, and the same thing in reverse is a motor. The generator is at the heart of a wind turbine, as it is what turns the rotation of the blades into electrical energy. A motor and generator look very similar, and many motors are used as generators with little or no modification.
To generate electricity, magnetic field lines must move at right angles to the wire in the coil.
In Figure 1 (right, top), the wind turbine blades rotate the magnetic field, which induces a current in the windings as it passes by them. In a real turbine there will be more rotating magnetic fields, inducing currents in several windings at the same time.
(below) shows the windings on this machine being wound by hand. The coil is a continuous length of copper wire fed from the reels behind the stator. This part of the generator does not move and so is called the stator. Figure 3
(right) shows the rotor, which is turned by the wind turbine blades. Magnets are attached to the outside of this rotor, which induce currents in the stator windings as they pass by. This is a simplified diagram showing how the rotor magnetic field rotates past all the stator wound coils in turn.