How a wind turbine works: we explain how a wind generator works for the production of electricity from the wind. Advantages and disadvantages of wind turbines.
L'wind energy has its roots in antiquity. As early as 3000 BC, navigators used the energy of the wind to transport their boats full of sails that unfolded in the wind.
In ancient Babylon, in 2000 BC, the first windmills were born, used to grind grain for the production of flours.
Today, thewind energy, is exploited to produce electricity thanks to the so-calledwind turbines; buthow a wind turbine works? The mechanism of operation of a wind turbine it is very simple to understand, above all because it is closely linked to the structure of the Windmill.
How a wind turbine is made
The wind turbine consists of one rotating shovel which represents the "sail of the system", the blades act as a barrier that opposes the wind so that the power of the wind will force the blades to rotate with the genesis of kinetic energy (energy dictated by the movement of the blades).
The wind turbines are connected to a rotor, in turn connected to the so-called "Tree", The rotor transfers themechanical energy (rotational energy) to the shaft that sends it to electric generator which is positioned on the other end of the shaft.
A generator is a device that uses the properties of electromagnetic induction to produce electrical voltage (a difference in electrical charge).
To better understand, it is possible to compare the "electrical voltage" to the "pressure", which is a force that moves electricity from one point to another. The generator consists of magnets and a conductor (a coiled wire). When you have a conductor surrounded by magnets and there is a part that is holding a rotary movement compared to the others, there is the genesis of a certain voltage in the conductor.
In other words, when the wind turns the rotor blades, the rotor turns the shaft, the shaft in turn turns a structure of the magnets transferring energy once again, at this point voltage will be generated in the coil of wire ( in the conductor) that will produce electric energy.
In a wind turbine we can highlight a large number of components, the main ones are:
it constitutes the beating heart of the machine, in fact it collects the generator, the gearboxes, the brakes, the pitch control and yaw control actuators.
it consists of the group of rotating blades, the hub, the shaft and the pitch control mechanism
- Support tower
plays an obvious structural role by supporting the machine. It has the task of absorbing the vibrations generated by the motion of the blades.
- Measurement systems
they can be more or less at the forefront. They sense the direction of the wind, have anemometers and more. They are mounted on the upper end of the nacelle. On the highest part of the wholewind turbine. Theirsoperationserves to correctly configure the entire machine according to the intensity and direction of the wind.
- Control systems
monitor the correct operation of the machine and act in the event of a breakdown to secure the entire structure of thewind turbine.
- Accessory systems
each developer has its own optional mechanisms. They generally allow you to optimize the use ofwind turbinewith remote control systems (remote control and management of the machine), automatic maintenance, hoists for lifts to allow access to staff ...
From wind to electricity, here's how
Essentially the generator transforms the energy of rotation into electrical energy by means of a game of energy transfer from one structure to another (from wind to blades -> rotor -> shaft -> generator). This just described is the operating mechanism linked to the simplest structures of the wind turbines, progress gave birth wind turbines more complex but all can be traced back to the scheme of energy transfer that goes from the wind to the blades up to the generator.
Wind energy, research
The components described above are the bases that make up a wind generator. It is important to point out that the wind sector is in continuous development. The most advanced aerodynamic knowledge, the search for new materials, the introduction of more sophisticated control systems ... make thewind turbinesdeveloped only a few years ago. The machines designed in recent times have rotors that can even exceed 100 meters in diameter!
How a wind turbine works
As explained above, the principle ofoperationat the base of awind turbineisseemingly simple: the force of the wind sets in motion a series of blades which are connected to a central pivot (hub or rotor). The wind, blowing, makes the blades turn which triggers a rotary movement around the axis of the pivot. Various devices are connected to the hub (brakes, multipliers ...) which transmit the motion generated by the rotating blades to the electric generator located at the base of the shaft.
At the heart of the operation of awind turbinethere is hisgenerator. The generator is the electromechanical organ that allows to produceelectricityaway from the wind. At first, the generators used for the production ofwind turbinesthey were synchronous type. Today only three-phase asynchronous generators are used. How does a wind power generator work? Theelectric generatorof awind blade workslike any other generator in a power plant.
As the wind speed increases, there is a progressive increase in the instantaneous power delivered by the machine, until the rated speed (rated wind speed) which allows the wind generator to reach its maximum power (cut-out wind speed). Once this threshold is exceeded, the wind generator activates a safety mechanism by which it stops working to avoid compromising the machine.
Thewind generator workslike any other generator in a power plant thanks to thespeed reducer. The speed reducer solves the problem of direct communication between rotor and alternator. When the wind blows strongly, the excessively high rotor number of revolutions would continuously trigger a defense mechanism of the generator, interrupting the production of wind energy. The speed reducer modulates the power delivered to the generator.
The development of alternators with a high number of pole pairs made it possible to fine-tune thewind turbineswithout reducer. In this context, the operating mechanism is slightly different due to the adoption of ad hoc alternators and speed multipliers. There are still few wind turbine manufacturers who have renounced the adoption of the gearbox, however research and development of new machines seem to point in this direction.