Types of wind turbines
Vane
For vane wind turbines, the highest efficiency which is achieved by the action of air flow perpendicular to the plane of rotation requires a device of automatic rotation axis of rotation. For this purpose, use the wing-stabilizer. Rotary wind turbines have the advantage that it can operate at any wind does not change his position. The utilization of wind energy (see Fig.. 9) y vane wind turbine is much higher than the carousel. At the same time, the carousel - a lot more torque.
It is maximum for rotary blade units at zero relative velocity of the wind. Distribution vane wind generators due to the velocity of their rotation. They can be directly connected to the generator of electric current without the multiplier. Speed vane wind turbines are inversely proportional to the number of wings, so the number of units with more than three blades is hardly used.
Rotary
The difference in the aerodynamics of revolving facilities provides an advantage in comparison with traditional windmills. With an increase in wind speed are rapidly increasing their traction, after which the speed is stabilized. Rotary low-speed wind turbines and it allows the use of simple electrical circuits, for example, with asynchronous generator, without risk to suffer an accident with a random gust of wind. Slow-speed makes one limiting requirement - the use of a multipolar generator operating at low engine speeds. Such generators are not widely spread, and the use of multipliers (multiplier [Lat. Multiplicator multiplying] - raising the gear is not effective because of the low efficiency of the latter. Even more important advantage of rotary design was its ability without additional tweaks to ensure "where the wind blows" that is very important for ground-wandering flows. wind turbines of this type are built in the United States , Japan , Britain , Germany and Canada . Rotary blade turbine is the easiest to use. Its design provides maximum torque at startup wind turbine and automatic self-regulation of the maximum rotational speed during operation. With increasing load decreases speed and increases torque up to a full stop.
Orthogonal
Orthogonal wind generators, as believed to hold promise for large energy. Today orthogonal designs are certain difficulties. Among them, in particular, the problem starts. In the orthogonal units use the same airfoil as in subsonic aircraft (see Fig. 8. (6)). Plane, before the "lean" on the lift of the wing, should disperse. The same is true in the case of orthogonal unit. First, her need to take energy - unleashes and brings to certain aerodynamic parameters, and only then she will move from the regime of the engine in the generator regime. PTO begins at a wind speed of about 5 m / s and rated power is achieved at a speed of 14- 16 m / sec. Preliminary calculations of wind envisage their use in a range from 50 to 20 000 kW. In a realistic setting power of 2000 kW diameter of the ring, which move the wings, is about 80 meters . In a strong wind turbine large sizes. However, you can do and small - to take a number, not size. Supply each individual power generator transformer can sum the output power provided by generators. In this case, the reliability and survivability of wind turbines.
Unexpected manifestations and use
Really working wind generators have found a number of negative phenomena. For example, the proliferation of wind farms could interfere with TV reception and create powerful sound vibrations. The emergence of an experimental wind turbine in the Orkney Islands ( United Kingdom ) in 1986 led to numerous complaints from viewers nearest settlements. As a result, some was built television repeater. Thumb wind turbine blades were made of fiberglass, which does not reflect or absorb radio waves. Interference created a steel frame and blades are available on these metal strips, designed to divert lightning strikes. They reflect and scatter a microwave signal. The reflected signal is mixed with the direct running from the transmitter, and created on the screen interference. Built in 1980 in the town of Boone ( USA ), wind power, giving 2 thousand kilowatts, operate smoothly, but also aroused criticism townspeople. While working windmill in the windows rattled and tinkled dishes on the shelves [17]. It was found that screw at a certain speed published infrasound. It is not felt by the human ear, but causes low-frequency oscillations of subjects and is not safe for humans. Revised blades of infrasound vibration were gone. Wind turbines can not only generate energy. The ability to attract the attention of the rotation without the expenditure of energy is used for advertising. The most simple - single-blade turbine carousel is a rectangular plate with curved edges (Figure 4.18). Pinned on the wall, he begins to rotate, even with little wind. A large area of the wings carousel three or four blade turbine can rotate advertising banners and a small generator. Stored in the battery electric power can cover the wings with advertising during the night, and in calm weather and rotate them.