The basic components of a wind turbine are as follows:
1. Rotor – three blades, mounted on a hub – typical rotor diameters are 80 90m for today’s larger machines. Blades are usually made from Glass Reinforced Plastic (GRP) and incorporate lightning protection measures. The picture below shows a single blade being transported to a wind farm site.
2. Nacelle – the “box” within which the main components are housed and home to the gearbox, generator and transformer as well as some of the control electronics. The picture below shows a nacelle being lifted onto the wind turbine tower (if you look closely you can see the construction team at the top of the tower waiting to fix the nacelle in to place)
3. Gearbox – converts the rotational speed of the rotor (typically 10-20rpm) to 1500rpm for the generator
4. Generator – converts rotational movement to electrical energy
1 Spinner
2 Spinner bracket
3 Blade
4 Pitch bearing
5 Rotor hub
6 Main bearing
7 Main shaft
8 Gearbox
9 Service crane
10 Brake disc
11 Coupling
12 Generator
13 Yaw Gear
14 Tower
15 Yaw Ring
16 Oil Filter
17 Generator Fan
18 Canopy
http://www.powergeneration.siemens.com
5. Transformer – converts electricity from 415V or 690V to 11,000V for transmission down the tower. The picture below shows transformer housing. The transformer can also be housed inside the wind turbine tower itself.
6. Tower – usually steel, a cylinder supporting the nacelle and rotor. Typical tower heights are 60-80m. Cables run down the tower taking the electricity from the generator at the top, into the ground and then onto a connection point to the grid. Lifts or ladders allow maintenance crew to access the nacelle. The picture below shows a 60m wind turbine tower.
7. Base – a concrete base, typically 15m x 15m x 1m which acts as the foundation for the structure.
1. Rotor
2. Nacelle
3. Gearbox
4. Generator
5. Transformer
6. Tower
7. Base
8. Nasty polluting 4×4 (not mine for clarification purposes)
Operation
When the wind blows the turbine hub turns into the wind. When the wind passes over the blade, the shape of the blade means that the air flows more quickly over one side of the blade than the other. This results in the turning of the rotor.
Wind turbines operate when the windspeed is within certain limits. There has to be enough wind for the blades to turn – typically 3-4m/s (or 7-9mph, 6-8 knots). When the windspeeds get to 25m/s (56mph, 49 knots), turbines typically shut down to protect the structure from excessive loads. Wind turbines are certified to specified levels and designed to the highest of these.
Instruments at the top of the nacelle (wind vane and anemometer) measure the wind speed and direction.
Control of the turbine
As windspeeds increase, so the energy generated by the turbine does as well. At some point where windspeeds are around 15m/s (34mph, 29 knots), the maximum (or rated) capacity of the turbine is reached. A limit has to be set to define the sizes of the various components – gearbox, generator, cables, rotor blades).
To control production of wind energy above the rated windspeed, the turbine can use various methods:
• Variable pitch – the blades of the wind turbine are feathered to limit the energy produced as windspeeds increase
• Variable speed – on some wind turbines, the rotor is allowed to speed up and slow down as the windspeed varies
In both cases, changes to the pitch or speed can happen several times a second so the wind turbine is always running in an optimised state for the wind conditions it sees, providing the most efficient extraction of energy from the wind and therefore maximising renewable energy production.
All of the information about the wind turbines are recorded by computers and transmitted to an off-site control centre. Wind turbines are for the majority of the time self sufficient although periodic mechanical checks are usually carried out every few months.
Nigel
January 11th, 2009
Great information thanks heaps
Linear Actuator
February 23rd, 2009
Great illustration.
Michael Hamrogue
March 31st, 2009
Hello
What is the cost of the wind turbine seen above and the installation?
How would you go about testing the speed of the wind on a site where a turbine maybe installed?
Any information is greatly appreciated
Regards
Michael
Vicky Portwain
April 1st, 2009
Hi Michael
The turbine pictured is a 2.5 Megawatt turbine. I am not sure if you are UK or US based. Currently wind turbine costs in the UK are over £1m ($1.44m) per Megawatt installed capacity – so this turbine would be £2.5m ($3.6m). I suspect that they are cheaper in the US due to greater economies of scale on most projects.
In terms of masts – in the UK, a company called Chillwind installs masts. Alternatively you can go to a wind energy development company who will pay all the wind speed monitoring and planning application costs.
Let me know if you need any more info.
Vicky
dawd
June 25th, 2009
Hello
what are the necessary requirements of components of a simple wind turbine and what do think the cost of the whole construction.
P.Saravanan
July 27th, 2009
I need blade information for your rotor
Vicky Portwain
July 27th, 2009
This turbine has 41 metre blades (82 metre rotor diameter)
Justin
October 30th, 2009
The base of the windturbine is quite huge. The turbines I work on have a base depth of 40ft. This depth is because of tower frequency and emergency stop. They are great machines and provide jobs and revenue for the surrounding communities.
Justin
October 30th, 2009
I’m sorry Vicky but you are incorrect. The blade length is not half of the rotor diameter. You are forgetting the hub length. As for cost of construction here’s an example. A 21 unit park producing 63 MW cost $1.2 million when it was completed in 2007. This included a 5 year O&M contract. There’s 3 years left on the contract and they have the option to renew.
Johan van der Hoeven
August 7th, 2010
I live in the Netherlands and we have quite a lot of these wind turbines. They’re even planning to build them in the North Sea.
piyush
October 20th, 2010
I wanna know about he price of the yaw and pitch gear only, not the whole yaw and pitch system, can any one help me
Kevin@wind turbine
October 29th, 2010
Well Turbines have blades that are turned by the wind; blades turn a shaft to which they are connected. The shaft in turn connected to generator, the mechanical energy is transferred into the generator through the shaft and converts it into electricity. This electricity can use in the home for any electrical need. Another benefit of wind turbine is that they can lower your electricity bill by 50-80%.
Thanks for your post i know this much only.
yasser
December 19th, 2010
can you help me to get the dimentions and design for a rotor hub in which we will fix on it three blades of 1 meter long and 1 Kg in weight
pleaze send them to me
yasser_electronics@hotmail.com
James
March 24th, 2011
Just create a couple thousands of these and the power trouble is over.