How to make a wind power plant with your own hands. How to make a vertical wind generator Wind generator from

Russia occupies a dual position with regard to wind energy resources. On the one hand, due to the huge total area and the abundance of flat areas, there is generally a lot of wind, and it is mostly even. On the other hand, our winds are predominantly low-potential and slow, see Fig. On the third, in sparsely populated areas the winds are violent. Based on this, the task of installing a wind generator on the farm is quite relevant. But in order to decide whether to buy a fairly expensive device or make it yourself, you need to think carefully about which type (and there are a lot of them) to choose for what purpose.

Basic Concepts

1. KIEV – wind energy utilization coefficient. When used to calculate a mechanistic model of flat wind (see below), it is equal to the efficiency of the rotor of a wind power plant (WPU).
2. Efficiency – end-to-end efficiency of the APU, from the oncoming wind to the terminals of the electric generator, or to the amount of water pumped into the tank.
3. Minimum operating wind speed (MRS) is the speed at which the windmill begins to supply current to the load.
4. The maximum permissible wind speed (MAS) is the speed at which energy production stops: the automation either turns off the generator, or puts the rotor in a weather vane, or folds it and hides it, or the rotor itself stops, or the APU is simply destroyed.
5. Starting wind speed (SW) - at this speed, the rotor is able to turn without load, spin up and enter operating mode, after which the generator can be turned on.
6. Negative starting speed (OSS) - this means that the APU (or wind turbine - wind power unit, or WEA, wind power unit) to start at any wind speed requires mandatory spin-up from an external source of energy.
7. Starting (initial) torque is the ability of a rotor, forcibly braked in the air flow, to create torque on the shaft.
8. Wind turbine (WM) is part of the APU from the rotor to the shaft of the generator or pump, or other energy consumer.
9. Rotary wind generator - an APU in which wind energy is converted into torque on the power take-off shaft by rotating the rotor in the air flow.
10. The range of rotor operating speeds is the difference between MMF and MRS when operating at rated load.
11. Low-speed windmill - in it linear speed parts of the rotor in the flow does not significantly exceed the wind speed or is lower than it. The dynamic pressure of the flow is directly converted into blade thrust.
12. High-speed windmill - the linear speed of the blades is significantly (up to 20 or more times) higher than the wind speed, and the rotor forms its own air circulation. The cycle of converting flow energy into thrust is complex.

Notes:

1. Low-speed APUs, as a rule, have a KIEV lower than high-speed ones, but have a starting torque sufficient to spin up the generator without disconnecting the load and zero TAC, i.e. Absolutely self-starting and usable in the lightest winds.
2. Slowness and speed are relative concepts. A household windmill at 300 rpm can be low-speed, but powerful APUs such as EuroWind, from which the fields of wind power plants and wind farms are assembled (see figure) and whose rotors make about 10 rpm, are high-speed, because with such a diameter, the linear speed of the blades and their aerodynamics over most of the span are quite “airplane-like”, see below.

What kind of generator do you need?

Electric generator for windmill household use must generate electricity in a wide range of rotation speeds and have the ability to self-start without automation or external power sources. In the case of using APU with OSS (spin-up wind turbines), which, as a rule, have high KIEV and efficiency, it must also be reversible, i.e. be able to work as an engine. At powers up to 5 kW this condition is satisfied electric cars with permanent magnets based on niobium (supermagnets); on steel or ferrite magnets you can count on no more than 0.5-0.7 kW.

Note: asynchronous alternating current generators or collector ones with a non-magnetized stator are completely unsuitable. When the wind force decreases, they will “go out” long before its speed drops to MPC, and then they will not start themselves.

The excellent “heart” of the APU with a power from 0.3 to 1-2 kW is obtained from an alternating current self-generator with a built-in rectifier; these are the majority now. First, they maintain an output voltage of 11.6-14.7 V over a fairly wide speed range without external electronic stabilizers. Secondly, the silicon valves open when the voltage on the winding reaches approximately 1.4 V, and before that the generator “does not see” the load. To do this, the generator needs to be spun up quite decently.

In most cases, a self-generator can be directly connected, without a gear or belt drive, to the shaft of a high-speed high-pressure engine, selecting the speed by selecting the number of blades, see below. “High-speed trains” have a low or zero starting torque, but the rotor, even without disconnecting the load, will have time to spin sufficiently before the valves open and the generator produces current.

Choosing according to the wind

Before deciding what type of wind generator to make, let’s decide on the local aerology. In gray-greenish(windless) areas of the wind map, only a sailing wind engine will be of any use(We’ll talk about them later). If you need a constant power supply, you will have to add a booster (rectifier with voltage stabilizer), charger, powerful battery, inverter 12/24/36/48 V DC to 220/380 V 50 Hz AC. Such a facility will cost no less than $20,000, and it is unlikely that it will be possible to remove long-term power of more than 3-4 kW. In general, with an unwavering desire for alternative energy, it is better to look for another source.

In yellow-green, low-wind places, if you need electricity up to 2-3 kW, you can use a low-speed vertical wind generator yourself. There are countless of them developed, and there are designs that are almost as good as industrially manufactured “blade blades” in terms of KIEV and efficiency.

If you plan to buy a wind turbine for your home, then it is better to focus on a wind turbine with a sail rotor. There are many controversies, and in theory everything is not yet clear, but they work. In the Russian Federation, “sailboats” are produced in Taganrog with a power of 1-100 kW.

In red, windy regions, the choice depends on the required power. In the range of 0.5-1.5 kW, homemade “verticals” are justified; 1.5-5 kW – purchased “sailboats”. “Vertical” can also be purchased, but will cost more than a horizontal APU. And finally, if you need a wind turbine with a power of 5 kW or more, then you need to choose between horizontal purchased “blades” or “sailboats”.

Note: Many manufacturers, especially the second tier, offer kits of parts from which you can assemble a wind generator with a power of up to 10 kW yourself. Such a kit will cost 20-50% less than a ready-made kit with installation. But before purchasing, you need to carefully study the aerology of the intended installation location, and then select the appropriate type and model according to the specifications.

About security

The parts of a wind turbine for household use in operation can have a linear speed exceeding 120 and even 150 m/s, and a piece of any solid material weighing 20 g, flying at a speed of 100 m/s, with a “successful” hit, will kill a healthy man outright. A steel or hard plastic plate 2 mm thick, moving at a speed of 20 m/s, cuts it in half.

In addition, most wind turbines with a power of more than 100 W are quite noisy. Many generate air pressure fluctuations of ultra-low (less than 16 Hz) frequencies - infrasounds. Infrasounds are inaudible, but are harmful to health and travel very far.

Note: in the late 80s there was a scandal in the United States - the largest wind farm in the country at that time had to be closed. Indians from a reservation 200 km from the field of its wind farm proved in court that their health disorders, which sharply increased after the wind farm was put into operation, were caused by its infrasounds.

Due to the above reasons, installation of APUs is allowed at a distance of at least 5 of their heights from the nearest residential buildings. In the courtyards of private households, it is possible to install industrially manufactured windmills that are appropriately certified. It is generally impossible to install APUs on roofs - during their operation, even low-power ones, alternating mechanical loads arise that can cause resonance building structure and its destruction.

Note: The height of the APU is considered to be the highest point of the swept disk (for bladed rotors) or geometric figure (for vertical APUs with a rotor on the shaft). If the APU mast or the rotor axis protrude even higher, the height is calculated by their top - the top.

Wind, aerodynamics, KIEV

A homemade wind generator obeys the same laws of nature as a factory one, calculated on a computer. And the do-it-yourselfer needs to understand the basics of his work very well - most often he does not have expensive, state-of-the-art materials and technological equipment at his disposal. The aerodynamics of the APU are oh so difficult...

Wind and KIEV

To calculate serial factory APUs, the so-called. flat mechanistic model of wind. It is based on the following assumptions:

• Wind speed and direction are constant within the effective rotor surface.
• Air is a continuous medium.
• The effective surface of the rotor is equal to the swept area.
• The energy of the air flow is purely kinetic.

Under such conditions, the maximum energy per unit volume of air is calculated using the school formula, assuming the air density under normal conditions is 1.29 kg*cubic. m. At a wind speed of 10 m/s, one cube of air carries 65 J, and from one square of the effective surface of the rotor, with 100% efficiency of the entire APU, 650 W can be removed. This is a very simplified approach - everyone knows that the wind is never perfectly even. But this has to be done to ensure repeatability of products - a common thing in technology.

The flat model should not be ignored, it gives a clear minimum of available wind energy. But air, firstly, is compressible, and secondly, it is very fluid (dynamic viscosity is only 17.2 μPa*s). This means that the flow can flow around the swept area, reducing the effective surface and KIEV, which is most often observed. But in principle, the opposite situation is also possible: the wind flows towards the rotor and the effective surface area will then be greater than the swept surface, and the KIEV will be greater than 1 relative to it for a flat wind.

Let's give two examples. The first is a pleasure yacht, quite heavy; the yacht can sail not only against the wind, but also faster than it. Wind means external; the apparent wind must still be faster, otherwise how will it pull the ship?

The second is a classic of aviation history. During tests of the MIG-19, it turned out that the interceptor, which was a ton heavier than the front-line fighter, accelerates faster in speed. With the same engines in the same airframe.

The theorists did not know what to think, and seriously doubted the law of conservation of energy. In the end, it turned out that the problem was the cone of the radar radome protruding from the air intake. From its toe to the shell, an air compaction arose, as if raking it from the sides to the engine compressors. Since then, shock waves have become firmly established in theory as useful, and the fantastic flight performance of modern aircraft is due in no small part to their skillful use.

Aerodynamics

The development of aerodynamics is usually divided into two eras - before N. G. Zhukovsky and after. His report “On attached vortices” dated November 15, 1905 was the beginning new era in aviation.

Before Zhukovsky, they flew with flat sails: it was assumed that the particles of the oncoming flow gave all their momentum to the leading edge of the wing. This made it possible to immediately get rid of the vector quantity - angular momentum - which gave rise to tooth-breaking and most often non-analytical mathematics, move to much more convenient scalar purely energy relations, and ultimately obtain a calculated pressure field on the load-bearing plane, more or less similar to the real one.

This mechanistic approach made it possible to create devices that could, at the very least, take to the air and fly from one place to another, without necessarily crashing to the ground somewhere along the way. But the desire to increase speed, load capacity and other flight qualities increasingly revealed the imperfections of the original aerodynamic theory.

Zhukovsky's idea was this: the air travels a different path along the upper and lower surfaces of the wing. From the condition of continuity of the medium (vacuum bubbles by themselves do not form in the air) it follows that the velocities of the upper and lower flows descending from the trailing edge should be different. Due to the small but finite viscosity of the air, a vortex should form there due to the difference in speeds.

The vortex rotates, and the law of conservation of momentum, just as immutable as the law of conservation of energy, is also valid for vector quantities, i.e. must also take into account the direction of movement. Therefore, right there, on the trailing edge, a counter-rotating vortex with the same torque should form. Due to what? Due to the energy generated by the engine.

For aviation practice, this meant a revolution: by choosing the appropriate wing profile, it was possible to send an attached vortex around the wing in the form of a circulation G, increasing its lift. That is, by spending part, and for high speeds and loads on the wing – most of the motor power, you can create an air flow around the device, allowing you to achieve better flight qualities.

This made aviation aviation, and not part of aeronautics: now aircraft could create for himself the environment necessary for flight and no longer be a toy of air currents. All you need is a more powerful engine, and more and more powerful...

KIEV again

But the windmill does not have a motor. On the contrary, it must take energy from the wind and give it to consumers. And here it turns out - his legs were pulled out, his tail got stuck. We used too little wind energy for the rotor’s own circulation - it will be weak, the thrust of the blades will be low, and the KIEV and power will be low. We will give a lot to the circulation - the rotor will be on idling spinning like crazy, but consumers again get little: they barely applied the load, the rotor slowed down, the wind blew away the circulation, and the rotor stopped.

The law of conservation of energy gives the “golden mean” right in the middle: we give 50% of the energy to the load, and for the remaining 50% we turn up the flow to the optimum. Practice confirms the assumptions: if the efficiency of a good pulling propeller is 75-80%, then the efficiency of a bladed rotor that is also carefully calculated and blown in a wind tunnel reaches 38-40%, i.e. up to half of what can be achieved with excess energy.

Modernity

Nowadays, aerodynamics, armed with modern mathematics and computers, is increasingly moving away from inevitably simplifying models to accurate description behavior of a real body in a real flow. And here, in addition to the general line - power, power, and once again power! – side paths are discovered, but promising precisely when the amount of energy entering the system is limited.

The famous alternative aviator Paul McCready created an airplane back in the 80s with two chainsaw motors with a power of 16 hp. showing 360 km/h. Moreover, its chassis was tricycle, non-retractable, and its wheels were without fairings. None of McCready's devices went online or went on combat duty, but two - one with piston engines and propellers, and the other a jet - flew around for the first time in history globe without landing at one gas station.

The development of the theory also affected the sails that gave birth to the original wing quite significantly. “Live” aerodynamics allowed the yachts to operate in winds of 8 knots. stand on hydrofoils (see figure); to accelerate such a monster to the required speed with a propeller, an engine of at least 100 hp is required. Racing catamarans sail at a speed of about 30 knots in the same wind. (55 km/h).

There are also finds that are completely non-trivial. Fans of the rarest and most extreme sport - base jumping - wearing a special wing suit, wingsuit, fly without a motor, maneuvering at a speed of more than 200 km/h (picture on the right), and then smoothly land in a pre-selected place. In which fairy tale do people fly on their own?

Many mysteries of nature were also resolved; in particular, the flight of a beetle. According to classical aerodynamics, it is not capable of flying. Just like the founder of the stealth aircraft, the F-117, with its diamond-shaped wing, is also unable to take off. And the MIG-29 and Su-27, which can fly tail first for some time, do not fit into any idea at all.

And why then, when working on wind turbines, not just fun and not a tool for destroying their own kind, but a source of a vital resource, do you need to dance away from the theory of weak flows with its flat wind model? Is there really no way to move forward?

What to expect from the classics?

However, one should not abandon the classics under any circumstances. It provides a foundation without which one cannot rise higher without relying on it. Just as set theory does not abolish the multiplication table, and quantum chromodynamics will not make apples fly up from the trees.

So, what can you expect with the classical approach? Let's look at the picture. On the left are types of rotors; they are depicted conditionally. 1 – vertical carousel, 2 – vertical orthogonal ( wind turbine); 2-5 – bladed rotors with different numbers of blades with optimized profiles.

On the right along the horizontal axis is the relative speed of the rotor, i.e., the ratio of the linear speed of the blade to the wind speed. Vertical up - KIEV. And down - again, relative torque. A single (100%) torque is considered to be that which is created by a rotor forcibly braked in the flow with 100% KIEV, i.e. when all the flow energy is converted into rotating force.

This approach allows us to draw far-reaching conclusions. For example, the number of blades must be selected not only and not so much according to the desired rotation speed: 3- and 4-blades immediately lose a lot in terms of KIEV and torque compared to 2- and 6-blades that work well in approximately the same speed range. And the outwardly similar carousel and orthogonal have fundamentally different properties.

In general, preference should be given to bladed rotors, except in cases where extreme low cost, simplicity, maintenance-free self-starting without automation are required, and lifting onto a mast is impossible.

Note: Let's talk about sailing rotors in particular - they don't seem to fit into the classics.

Verticals

APUs with a vertical axis of rotation have an undeniable advantage for everyday life: their components requiring maintenance are concentrated at the bottom and no lifting is required. There remains, and even then not always, a thrust-support self-aligning bearing, but it is strong and durable. Therefore, when designing a simple wind generator, the selection of options should begin with verticals. Their main types are presented in Fig.

Sun

In the first position is the simplest one, most often called the Savonius rotor. In fact, it was invented in 1924 in the USSR by J. A. and A. A. Voronin, and the Finnish industrialist Sigurd Savonius shamelessly appropriated the invention, ignoring the Soviet copyright certificate, and began serial production. But the introduction of an invention in the future means a lot, so in order not to stir up the past and not disturb the ashes of the deceased, we will call this windmill a Voronin-Savonius rotor, or for short, VS.

The aircraft is good for the home-made man, except for the “locomotive” KIEV at 10-18%. However, in the USSR they worked a lot on it, and there are developments. Below we will look at an improved design, not much more complex, but according to KIEV, it gives bladers a head start.

Note: the two-blade aircraft does not spin, but jerks jerkily; The 4-blade is only slightly smoother, but loses a lot in KIEV. To improve, 4-trough blades are most often divided into two floors - a pair of blades below, and another pair, rotated 90 degrees horizontally, above them. KIEV is preserved, and the lateral loads on the mechanics weaken, but the bending loads increase somewhat, and with a wind of more than 25 m/s such an APU is on the shaft, i.e. without a bearing stretched by cables above the rotor, it “tears down the tower.”

Daria

Next is the Daria rotor; KIEV – up to 20%. It is even simpler: the blades are made of a simple elastic tape without any profile. The theory of the Darrieus rotor is not yet sufficiently developed. It is only clear that it begins to unwind due to the difference in the aerodynamic resistance of the hump and the tape pocket, and then it becomes sort of high-speed, forming its own circulation.

The rotational moment is small, and in the starting positions of the rotor parallel and perpendicular to the wind it is completely absent, so self-spin-up is possible only with an odd number of blades (wings?) In any case, the load from the generator must be disconnected during spin-up.

The Daria rotor has two more bad qualities. Firstly, when rotating, the thrust vector of the blade describes a full rotation relative to its aerodynamic focus, and not smoothly, but jerkily. Therefore, the Darrieus rotor quickly breaks down its mechanics even in a steady wind.

Secondly, Daria not only makes noise, but screams and squeals, to the point that the tape breaks. This happens due to its vibration. And the more blades, the stronger the roar. So, if they make Daria, they have two blades, from expensive, high-strength sound-absorbing materials (carbon, mylar), and a small aircraft is used for spinning in the middle of the mast-pole.

Orthogonal

At pos. 3 – orthogonal vertical rotor with profiled blades. Orthogonal because the wings stick out vertically. The transition from BC to orthogonal is illustrated in Fig. left.

The angle of installation of the blades relative to the tangent to the circle touching the aerodynamic foci of the wings can be either positive (in the figure) or negative, depending on the wind force. Sometimes the blades are made rotating and weather vanes are placed on them, automatically holding the “alpha”, but such structures often break.

The central body (blue in the figure) allows you to increase the KIEV to almost 50%. In a three-bladed orthogonal, it should have the shape of a triangle in cross-section with slightly convex sides and rounded corners, and with a larger number of blades a simple cylinder is sufficient. But the theory for the orthogonal gives an unambiguous optimal number of blades: there should be exactly 3 of them.

Orthogonal refers to high-speed wind turbines with OSS, i.e. necessarily requires promotion during commissioning and after calm. According to the orthogonal scheme, serial maintenance-free APUs with a power of up to 20 kW are produced.

Helicoid

Helicoidal rotor, or Gorlov rotor (item 4) is a type of orthogonal that ensures uniform rotation; an orthogonal with straight wings “tears” only slightly weaker than a two-bladed aircraft. Bending the blades along a helicoid allows one to avoid losses of CIEV due to their curvature. Although the curved blade rejects part of the flow without using it, it also rake part into the zone of the highest linear speed, compensating for losses. Helicoids are used less often than other wind turbines, because Due to the complexity of manufacturing, they are more expensive than their counterparts of equal quality.

Barrel raking

For 5 pos. – BC type rotor surrounded by a guide vane; its diagram is shown in Fig. right. It is rarely found in industrial applications, because expensive land acquisition does not compensate for the increase in capacity, and the material consumption and complexity of production are high. But a do-it-yourselfer who is afraid of work is no longer a master, but a consumer, and if you need no more than 0.5-1.5 kW, then for him a “barrel-raking” is a tidbit:

• A rotor of this type is absolutely safe, silent, does not create vibrations and can be installed anywhere, even on a playground.
• Bending a galvanized “trough” and welding a frame of pipes is nonsense work.
• The rotation is absolutely uniform, the mechanical parts can be taken from the cheapest or from the trash.
• Not afraid of hurricanes - too strong a wind cannot push into the “barrel”; a streamlined vortex cocoon appears around it (we will encounter this effect later).
• And the most important thing is that since the surface of the “barrel” is several times larger than that of the rotor inside, the KIEV can be over-unity, and the rotational moment already at 3 m/s for a “barrel” of three-meter diameter is such that a 1 kW generator with a maximum load of They say it’s better not to twitch.

Video: Lenz wind generator

In the 60s in the USSR, E. S. Biryukov patented a carousel APU with a KIEV of 46%. A little later, V. Blinov achieved 58% KIEV from a design based on the same principle, but there is no data on its tests. And full-scale tests of Biryukov’s APU were carried out by employees of the magazine “Inventor and Innovator”. A two-story rotor with a diameter of 0.75 m and a height of 2 m spun at full power in a fresh wind asynchronous generator 1.2 kW and withstood 30 m/s without breakdown. Drawings of Biryukov's APU are shown in Fig.

1. rotor made of galvanized roofing;
2. self-aligning double row ball bearing;
3. shrouds – 5 mm steel cable;
4. axis-shaft – steel pipe with a wall thickness of 1.5-2.5 mm;
5. aerodynamic speed control levers;
6. speed control blades – 3-4 mm plywood or sheet plastic;
7. speed control rods;
8. speed controller load, its weight determines the rotation speed;
9. drive pulley - a bicycle wheel without a tire with a tube;
10. thrust bearing - thrust bearing;
11. driven pulley – standard generator pulley;
12. generator.

Biryukov received several copyright certificates for his APU. First, pay attention to the cut of the rotor. When accelerating, it works like an aircraft, creating a large starting torque. As it spins, a vortex cushion is created in the outer pockets of the blades. From the wind's point of view, the blades become profiled and the rotor becomes a high-speed orthogonal, with the virtual profile changing according to the wind strength.

Secondly, the profiled channel between the blades acts as a central body in the operating speed range. If the wind intensifies, then a vortex cushion is also created in it, extending beyond the rotor. The same vortex cocoon appears as around the APU with a guide vane. The energy for its creation is taken from the wind, and it is no longer enough to break the windmill.

Thirdly, the speed controller is intended primarily for the turbine. It keeps its speed optimal from the KIEV point of view. And the optimum generator rotation speed is ensured by the choice of mechanical transmission ratio.

Note: after publications in the IR for 1965, the Armed Forces of Ukraine Biryukova sank into oblivion. The author never received a response from the authorities. The fate of many Soviet inventions. They say that some Japanese became a billionaire by regularly reading Soviet popular-technical magazines and patenting everything worthy of attention.

Lopastniki

As stated, according to the classics, a horizontal wind generator with a bladed rotor is the best. But, firstly, it needs a stable wind of at least medium strength. Secondly, the design for a do-it-yourselfer is fraught with many pitfalls, which is why often the fruit of long hard work, at best, illuminates a toilet, hallway or porch, or even turns out to only be able to unwind itself.

According to the diagrams in Fig. Let's take a closer look; positions:

• Fig. A:

1. rotor blades;
2. generator;
3. generator frame;
4. protective weather vane (hurricane shovel);
5. current collector;
6. chassis;
7. swivel unit;
8. working weather vane;
9. mast;
10. clamp for the shrouds.

• Fig. B, top view:

1. protective weather vane;
2. working weather vane;
3. protective weather vane spring tension regulator.

• Fig. G, current collector:

1. collector with copper continuous ring busbars;
2. spring-loaded copper-graphite brushes.

Note: Hurricane protection for a horizontal blade with a diameter of more than 1 m is absolutely necessary, because he is not capable of creating a vortex cocoon around himself. With smaller sizes, it is possible to achieve a rotor endurance of up to 30 m/s with propylene blades.

So, where do we stumble?

Blades

Expect to achieve power on the generator shaft of more than 150-200 W on blades of any size cut from thick-walled plastic pipe, as is often advised, are the hopes of a hopeless amateur. A pipe blade (unless it is so thick that it is simply used as a blank) will have a segmented profile, i.e. its top or both surfaces will be arcs of a circle.

Segmented profiles are suitable for incompressible media, such as hydrofoils or propeller blades. For gases, a blade of variable profile and pitch is needed, for an example, see Fig.; span - 2 m. This will be a complex and labor-intensive product, requiring painstaking calculations based on theory, pipe blowing and full-scale testing.

Generator

If the rotor is mounted directly on its shaft, the standard bearing will soon break - there is no equal load on all the blades in windmills. You need an intermediate shaft with a special support bearing and a mechanical transmission from it to the generator. For large windmills, the support bearing is a self-aligning double-row one; in the best models - three-tiered, Fig. D in Fig. higher. This allows the rotor shaft not only to bend slightly, but also to move slightly from side to side or up and down.

Note: It took about 30 years to develop a support bearing for the EuroWind type APU.

Emergency weather vane

The principle of its operation is shown in Fig. B. The wind, intensifying, puts pressure on the shovel, the spring stretches, the rotor warps, its speed drops and eventually it becomes parallel to the flow. Everything seems to be fine, but it was smooth on paper...

On a windy day, try holding a boiler lid or a large saucepan by the handle parallel to the wind. Just be careful - the fidgety piece of iron can hit you in the face so hard that it will bruise your nose, cut your lip, or even knock out your eye.

Flat wind occurs only in theoretical calculations and, with sufficient accuracy for practice, in wind tunnels. In reality, a hurricane damages windmills with a hurricane shovel more than completely defenseless ones. It’s better to change damaged blades than to do everything again. In industrial installations it is a different matter. There, the pitch of the blades, each individually, is monitored and adjusted by automation under the control of the on-board computer. And they are made from heavy-duty composites, not water pipes.

Current collector

This is a regularly serviced unit. Any power engineer knows that the commutator with brushes needs to be cleaned, lubricated, and adjusted. And the mast is from water pipe. If you can’t climb, once every month or two you’ll have to throw the entire windmill down to the ground and then pick it up again. How long will he last from such “prevention”?

Video: bladed wind generator + solar panel for power supply to a dacha

Mini and micro

But as the size of the paddle decreases, the difficulties fall according to the square of the wheel diameter. It is already possible to manufacture a horizontal bladed APU on your own with a power of up to 100 W. A 6-bladed one would be optimal. With more blades, the diameter of the rotor designed for the same power will be smaller, but they will be difficult to firmly attach to the hub. Rotors with less than 6 blades need not be taken into account: a 2-blade 100 W rotor needs a rotor with a diameter of 6.34 m, and a 4-blade of the same power needs 4.5 m. For a 6-blade, the power-diameter relationship is expressed as follows :

• 10 W – 1.16 m.
• 20 W – 1.64 m.
• 30 W – 2 m.
• 40 W – 2.32 m.
• 50 W – 2.6 m.
• 60 W – 2.84 m.
• 70 W – 3.08 m.
• 80 W – 3.28 m.
• 90 W – 3.48 m.
• 100 W – 3.68 m.
• 300 W – 6.34 m.

It would be optimal to count on a power of 10-20 W. Firstly, a plastic blade with a span of more than 0.8 m without additional measures protection will not withstand winds of more than 20 m/s. Secondly, with a blade span of up to the same 0.8 m, the linear speed of its ends will not exceed the wind speed by more than three times, and the requirements for profiling with twist are reduced by orders of magnitude; here a “trough” with a segmented pipe profile, pos. B in Fig. And 10-20 W will provide power to a tablet, recharge a smartphone, or illuminate a house-saving light bulb.

Next, select a generator. Great Chinese will do motor – wheel hub for electric bicycles, pos. 1 in Fig. Its power as a motor is 200-300 W, but in generator mode it will give up to about 100 W. But will it suit us in terms of speed?

The speed index z for 6 blades is 3. The formula for calculating the rotation speed under load is N = v/l*z*60, where N is the rotation speed, 1/min, v is the wind speed, and l is the rotor circumference. With a blade span of 0.8 m and a wind of 5 m/s, we get 72 rpm; at 20 m/s – 288 rpm. A bicycle wheel also rotates at approximately the same speed, so we will take off our 10-20 W from a generator capable of producing 100. You can place the rotor directly on its shaft.

But here the following problem arises: after spending a lot of work and money, at least on a motor, we got... a toy! What is 10-20, well, 50 W? But you can’t make a bladed windmill capable of powering even a TV at home. Is it possible to buy a ready-made mini-wind generator, and wouldn’t it be cheaper? As much as possible, and as cheaply as possible, see pos. 4 and 5. In addition, it will also be mobile. Place it on a stump and use it.

The second option is if it’s lying around somewhere stepper motor from an old 5- or 8-inch floppy drive, or from the paper drive or carriage of an unusable inkjet or dot matrix printer. It can work as a generator, and attach a carousel rotor to it from tin cans(pos. 6) is easier than assembling a structure like the one shown in pos. 3.

In general, the conclusion regarding “blade blades” is clear: homemade ones are more likely for tinkering to your heart’s content, but not for real long-term energy output.

Video: the simplest wind generator for lighting a dacha

Sailboats

The sailing wind generator has been known for a long time, but soft panels on its blades (see figure) began to be made with the advent of high-strength wear-resistant synthetic fabrics and films. Multi-bladed windmills with rigid sails are widely distributed around the world as a drive for low-power automatic water pumps, but their technical specifications are lower even than those of carousels.

However, a soft sail like a windmill wing, it seems, turned out to be not so simple. The point is not about wind resistance (manufacturers do not limit the maximum permissible wind speed): sailboat sailors already know that it is almost impossible for the wind to tear the panel of a Bermuda sail. Most likely, the sheet will be torn out, or the mast will be broken, or the whole vessel will make an “overkill turn.” It's about energy.

Unfortunately, exact test data cannot be found. Based on user reviews, it was possible to create “synthetic” dependencies for the installation of a Taganrog-made wind turbine-4.380/220.50 with a wind wheel diameter of 5 m, a wind head weight of 160 kg and a rotation speed of up to 40 1/min; they are presented in Fig.

Of course, there can be no guarantees for 100% reliability, but it is clear that there is no smell of a flat-mechanistic model here. There is no way a 5-meter wheel in a flat wind of 3 m/s can produce about 1 kW, at 7 m/s reach a plateau in power and then maintain it until a severe storm. Manufacturers, by the way, state that the nominal 4 kW can be obtained at 3 m/s, but when installed by forces based on the results of studies of local aerology.

There is also no quantitative theory to be found; The developers' explanations are unclear. However, since people buy Taganrog wind turbines and they work, we can only assume that the declared conical circulation and propulsive effect are not a fiction. In any case, they are possible.

Then, it turns out, IN FRONT of the rotor, according to the law of conservation of momentum, a conical vortex should also arise, but expanding and slow. And such a funnel will drive the wind towards the rotor, its effective surface will be more swept, and the KIEV will be more than unity.

Field measurements of the pressure field in front of the rotor, even with a household aneroid, could shed light on this issue. If it turns out to be higher than on the sides, then, indeed, the sailing APUs work like a beetle flies.

Homemade generator

From what has been said above, it is clear that it is better for homemade craftsmen to take on either verticals or sailboats. But both are very slow, and transmission to a high-speed generator is extra work, extra costs and losses. Is it possible to make an efficient low-speed electric generator yourself?

Yes, you can, on magnets made of niobium alloy, the so-called. supermagnets. The manufacturing process of the main parts is shown in Fig. Coils - each of 55 turns of 1 mm copper wire in heat-resistant high-strength enamel insulation, PEMM, PETV, etc. The height of the windings is 9 mm.

Pay attention to the grooves for the keys in the rotor halves. They must be positioned so that the magnets (they are glued to the magnetic core with epoxy or acrylic) converge with opposite poles after assembly. “Pancakes” (magnetic cores) must be made of a soft magnetic ferromagnet; Regular structural steel will do. The thickness of the “pancakes” is at least 6 mm.

In general, it is better to buy magnets with an axial hole and tighten them with screws; supermagnets attract with terrible force. For the same reason, a cylindrical spacer 12 mm high is placed on the shaft between the “pancakes”.

The windings that make up the stator sections are connected according to the diagrams also shown in Fig. The soldered ends should not be stretched, but should form loops, otherwise the epoxy with which the stator will be filled may harden and break the wires.

The stator is poured into the mold to a thickness of 10 mm. There is no need to center or balance, the stator does not rotate. The gap between the rotor and stator is 1 mm on each side. The stator in the generator housing must be securely secured not only from displacement along the axis, but also from rotation; a strong magnetic field with current in the load will pull it along with it.

Video: DIY windmill generator

Conclusion

And what do we have in the end? The interest in “blade blades” is explained rather by their spectacular appearance, than actual performance in a home-made version and at low power. A homemade carousel APU will provide “standby” power for charging a car battery or power supply small house.

But with sailing APUs it is worth experimenting with craftsmen with a creative streak, especially in the mini version, with a wheel 1-2 m in diameter. If the developers’ assumptions are correct, then it will be possible to remove all 200-300 W from this one, using the Chinese engine-generator described above.

Andrey said:

Thank you for your free consultation... And the prices “from companies” are not really expensive, and I think that craftsmen from the outback will be able to make generators similar to yours. And Li-po batteries can be ordered from China, inverters in Chelyabinsk make very good ones (with smooth sine). And sails, blades or rotors are another reason for the flight of thought of our handy Russian men.

Ivan said:

question:
For windmills with a vertical axis (position 1) and the “Lenz” option, it is possible to add an additional part - an impeller that points in the direction of the wind, and covers the useless side from it (going towards the wind). That is, the wind will not slow down the blade, but this “screen”. Positioning downwind with the “tail” located behind the windmill itself below and above the blades (ridges). I read the article and an idea was born.

By clicking the “Add comment” button, I agree with the site.

Power homemade wind generator will be enough to charge the batteries of various equipment, provide lighting and generally operate household electrical appliances. By installing a wind generator, you will save yourself from energy costs. If desired, the unit in question can be assembled with your own hands. You just need to decide on the basic parameters of the wind generator and do everything in accordance with the instructions.

The design of a wind generator includes several blades that rotate under the influence of wind currents. As a result of this impact, rotational energy is created. The generated energy is fed through the rotor to the multiplier, which in turn transmits the energy to the electric generator.

There are also designs of wind generators without multipliers. The absence of a multiplier makes it possible to significantly increase the productivity of the installation.

Wind generators can be installed either individually or in groups combined into a wind farm. Wind turbines can also be combined with diesel generators, which will save fuel and ensure the most efficient operation of the home's electrical system.

What do you need to know before starting to assemble a wind generator?

Before you start assembling a wind generator, you need to decide on a number of basic points.

First step. Select the appropriate type of wind turbine design. Installation can be vertical or horizontal. In case self-assembly It’s better to choose vertical models, because they are easier to manufacture and balance.

Second step. Determine the appropriate power. At this point, everything is individual - focus on your own needs. To obtain more power, you need to increase the diameter and weight of the impeller.

Increasing these characteristics will lead to certain difficulties at the stage of securing and balancing the wind generator wheel. Consider at the moment and objectively assess your capabilities. If you are a beginner, consider installing several medium-power wind generators instead of one very efficient unit.

Third step. Consider whether you can make all the elements of the wind generator yourself. Each part must be accurately calculated and made in full accordance with factory analogues. If you do not have the necessary skills, it is better to buy ready-made elements.

Fourth step. Select suitable batteries. It is better to refuse car batteries, because... they are short-lived, explosive and demanding to care for and maintain.

Sealed batteries are a better option. They cost a couple of times more, but they last several times longer and generally have better performance.

Pay special attention to choosing the appropriate number of blades. The most popular are wind generators with 2 and 3 blades. However, such installations have a number of disadvantages.

When a generator with 2 or 3 blades operates, powerful centrifugal and gyroscopic forces occur. Under the influence of the mentioned forces, the load on the main elements of the wind generator increases significantly. Moreover, at some moments the forces act in opposition to each other.

To level out the incoming loads and maintain the integrity of the wind generator structure, you need to perform competent aerodynamic calculation of the blades and manufacture them in exact accordance with the calculated data. Even minimal errors reduce the efficiency of the installation several times and increase the likelihood of an early breakdown of the wind generator.

When high-speed wind turbines operate, a lot of noise is created, especially when it comes to home-made installations. The larger the blades, the louder the noise will be. This point imposes a number of restrictions. For example, it will no longer be possible to install such a noisy structure on the roof of a house, unless, of course, the owner likes the feeling of living in an airfield.

Keep in mind that as the number of blades increases, the level of vibration generated during operation of the wind generator will increase. Two-blade units are more difficult to balance, especially for an inexperienced user. Consequently, there will be a lot of noise and vibration from windmills with two blades.

Give your choice to a wind generator with 5-6 blades. Practice shows that such models are the most optimal for self-production and use at home.

It is recommended to make the screw with a diameter of about 2 m. Almost anyone can handle the work of assembling and balancing it. Once you gain experience, you can try to assemble and install a wheel with 12 blades. Assembling such a unit will require more effort. Material consumption and time costs will also increase. However, 12 blades will allow you to receive power at the level of 450-500 W even with a light wind of 6-8 m/s.

Keep in mind that with 12 blades the wheel will be quite slow, and this can lead to various problems. For example, you will have to assemble a special gearbox, which is more complex and expensive to manufacture.

Thus, the best option for a novice home craftsman is a wind generator with a 200 cm diameter wheel equipped with blades medium length in the amount of 6 pieces.

Assembly components and tools

Assembling a windmill will require many different components and accessories. Gather and buy everything you need in advance so you don't have to worry about it in the future.

Depending on the conditions of a particular situation, a list necessary tools may vary a little. At this point, you will independently navigate the progress of the work.

Step-by-step guide to assembling a wind generator

The assembly and installation of a homemade wind generator is carried out in several stages.

First stage. Prepare three-point concrete base. Determine the depth and overall thickness of the foundation in accordance with the type of soil and climatic conditions at the construction site. Allow the concrete to harden for 1-2 weeks and install the mast. To do this, bury the support mast approximately 50-60 cm into the ground and secure it with guy wires.

Second stage. Prepare the rotor and pulley. The pulley is a friction wheel. There is a groove or rim around the circumference of such a wheel. When choosing the rotor diameter, you need to focus on the average annual wind speed. So, at an average speed of 6-8 m/s, a rotor with a diameter of 5 m will be more efficient than a rotor with a diameter of 4 m.

Third stage. Make the blades of the future wind generator. To do this, take a barrel and divide it into several equal parts in accordance with the selected number of blades. Mark the blades with a marker and then cut out the elements. A grinder is perfect for cutting; you can also use metal scissors.

Fourth stage. Attach the bottom of the barrel to the generator pulley. Use bolts for fastening. After this, you need to bend the blades on the barrel. Do not overdo it, otherwise the finished installation will be unstable. Set the appropriate rotation speed of the wind generator by changing the bends of the blades.

Fifth stage. Connect the wires to the generator and assemble them into a circuit in a dose. Attach the generator to the mast. Connect the wires to the generator and mast. Assemble the generator into a circuit. Also connect the battery to the circuit. Please note that the maximum permissible wire length for this installation is 100 cm. Connect the load using wires.

It takes an average of 3-6 hours to assemble one generator, depending on the skills available and the overall efficiency of the craftsman.

The wind generator requires regular care and maintenance.

1. 2-3 weeks after installing a new generator you need dismantle the device and make sure that the existing fastenings are secure. For your own safety, check the mounts only in light wind conditions.
2. Lubricate bearings at least once every 6 months. When the first signs of wheel imbalance appear, immediately remove it and eliminate any problems. The most common sign of imbalance is uncharacteristic shaking of the blades.
3. Check the pantograph brushes at least once every 6 months. Every 2-6 years paint metal elements installations. Regular painting will protect the metal from destruction due to corrosion.
4. Monitor the condition of the generator. Regularly check that the generator is not overheating during operation. If the surface of the unit becomes so hot that it becomes very difficult to hold your hand on it, take the generator to a workshop.
5. Monitor the condition of the collector. Any contamination must be as soon as possible delete from contacts, because they significantly reduce the efficiency of the installation. Keep an eye on the mechanical condition of the contacts. Overheating of the unit, burnt windings and other similar defects - all this must be eliminated immediately.

Thus, there is nothing complicated in assembling a wind generator. It is enough just to prepare all the necessary elements, assemble the installation according to the instructions and connect the finished unit to the electrical network. Right assembled wind generator for the home will become a reliable source of free electricity. Follow the instructions you received and everything will work out.

Good luck!

Video - Do-it-yourself wind generators for home

Until recently, wind generators were considered a rarity, but today this area is rapidly developing, and many have gained experience in creating wind turbines to generate electricity. Such devices can be used in the most different areas– for water supply, electrification of private houses, operation of agricultural units (for example, crushers) or heating water for the purpose of heating a home.

U industrial models a lot of advantages, except for the cost. Therefore, today we will find out how to make a wind generator with our own hands and what materials/tools will be needed for this.

Design features and mechanics of a wind generator

The principle of operation of a wind generator is to convert kinetic energy into electricity. The device consists of a number of system elements, each of which has its own function. Let's try to figure this out.

Pay attention! Wind generators can be rotary (vertical) or classic (horizontal). The latter have a higher efficiency, which is why they are made more often than others.

It is worth noting that vertical windmills must be turned towards the wind, because they are simply unable to function with a side flow. Horizontal generators have other advantages. Let's get to know them.

1. Turbines rotary devices will “catch” the wind regardless of which direction it blows from. Which is extremely convenient in case of unstable/variable wind in the region.
2. It is much easier to build a horizontal windmill than a horizontal one.
3. The structure can be located directly on the ground, but provided that there is enough wind there.

As for the disadvantages, a horizontal wind generator has only one - a rather low efficiency.

Calculating the power of the future wind generator

First, you should find out what power a wind generator should have with your own hands, what are the functions and loads that it will face. As a rule, alternative sources electricity are used as auxiliary, that is, intended to assist the main power supply. Therefore, if the system power is even 500 watts or more, this is already quite good.

Pay attention! To heat private house, which is of medium size, you will need about two to three kilowatts.

At the same time, the final power of a wind generator depends on other factors, including:

• wind speed;
• number of blades.

To find out the appropriate ratio for horizontal type devices, we recommend that you familiarize yourself with the table below. The numbers in it at the intersection are the required power (indicated in watts).

Table. Calculation of the required power for horizontal wind generators.

1m	3	8	15	27	42	63	90	122	143
2m	13	31	63	107	168	250	357	490	650
3m	30	71	137	236	376	564	804	1102	1467
4m	53	128	245	423	672	1000	1423	1960	2600
5m	83	166	383	662	1050	1570	2233	3063	4076
6m	120	283	551	953	1513	2258	3215	4410	5866
7m	162	384	750	1300	2060	3070	4310	6000	8000
8m	212	502	980	1693	2689	4014	5715	7840	10435
9m	268	653	1240	2140	3403	5080	7230	9923	13207

For example, if in your region the wind speed is predominantly from 5 to 8 meters per second, and the required wind generator power is 1.5-2 kilowatts, then the diameter of the structure should be approximately 6 meters or more.

What should the blades be like?

The shape of the blades can be:

• sailing;
• winged

As for sail-type blades, they are flat and therefore less efficient. They do not take into account aerodynamics, but spin exclusively under the pressure of the wind flow. As a result, no more than 10 percent of all energy is converted into electrical energy. But for wing blades, the area of ​​the internal and external surfaces is different. It is also worth noting that such blades should be located at an angle of 7-10 degrees relative to the wind.

Now a few words about the material from which the blades should be. For vintage windmills Tonic frames made of wood were used, consisting of poles and lintels. Special “wings” made of fabric were stretched onto such frames. If the fabric wore out, it was simply replaced with a new one. Although there is an alternative option - to use dense materials (for example, tarpaulin) for these purposes.

Although you can make blades with your own hands from more modern materials.

1. If the propeller is small, then cut polyvinyl chloride pipes can serve as blades for it.
2. You can also use light metals (for example, duralumin).
3. If you plan to use “sails,” they can be cut from plywood.
4. Finally, for a large unit, the blades can be made from boards (even if they are heavy, it doesn’t matter, they just need to balance each other).

Pay attention! If gusty winds prevail in the region, it is better to give preference to heavy blades - this will ensure more stable operation of the entire system.

As for the diameter of the pipes, it should correspond to 1/5 of their total length. Each of these pipes is cut lengthwise into four pieces, and at the base it is necessary to cut a rectangle measuring 5x5 (the fastenings will be located here), and after that, make an oblique cut, thanks to which each blade will taper from the base. Sandpaper is used to process the torn edge.

Making a vertical wind generator at home

Now let’s find out how to actually make a wind generator with your own hands. The procedure consists of several stages; let’s get acquainted with the features of each of them.

Stage one. We prepare tools and materials

There are no requirements regarding the size of the turbine - the larger it is, the better for the system itself. And in the example given in this article, the diameter of the turbine is 60 centimeters.

To make a vertical turbine yourself, prepare in advance:

• a pipe with a diameter of 60 centimeters made of stainless steel;
• screws, nuts and other fasteners;
• a pair of plastic disks with a diameter of 60 centimeters (it is important that the plastic is durable);
• a hub from a car for the base;
• corners with which the blades will be attached (six pieces for each element; that is, 36 copies in total).

In addition, take care of the following tools in advance:

• keys;
• jigsaw;
• mask;
• protective gloves;
• Bulgarian;
• screwdriver;
• electric drill.

To balance the blades, magnets or small metal plates. If the imbalance is minor, you can simply drill holes in the appropriate places.

Stage two. Makes a drawing

You definitely can’t do without a drawing here. You can use the one below or create your own.

Stage three. Making a vertical windmill

Step 1. First take metal pipe and cut it lengthwise so that you end up with six blades of the same size.

Step 2. Cut a pair of identical circles with a diameter of 60 centimeters from plastic. They will serve as supports for the lower and upper parts of the turbine.

Step 3. You can cut a small hole in the upper support (about 30 centimeters in diameter), which will make the structure somewhat lighter.

Step 4. Mark along the holes on the car hub similar holes in the lower plastic support required for fastenings. Use a drill to make holes.

Step 5. Mark the location of the blades in accordance with the template (you should get a pair of triangles that seem to form a star). Mark the mounting locations for the corners. Everything should be the same on both supports.

Step 6. Trim the blades. You can cut them several at a time using a grinder.

Step 7 Mark the mounting locations on the blades and corners. Make all these holes.

Step 8 Connect the blades to the bases using angles, bolts and nuts.

Pay attention! The power of the device largely depends on the length of the blades, but if the latter are large, it will be much more difficult to balance them. Moreover, the structure can become loose under the influence of strong winds.

Stage four. We make a generator

In this case, the generator must be self-exciting, and necessarily at permanent magnets. If you take a regular generator from a car, then the voltage winding here operates from the battery, in other words, in the absence of voltage there will be no excitation. Consequently, if you use a simple generator in tandem with a battery, and the wind is relatively weak for a long time, the battery will soon simply discharge, and later, when the wind returns, the wind generator will not start again with your own hands.

It is also possible to make a system using neodymium magnets. This kind of device will produce from 1.5 kilowatts (if the wind is weak) to 3.5 kilowatts (if the wind is strong). Step by step instructions to create such a generator is as follows.

Step 1. Make a couple of metal pancakes, each about 50 centimeters long.

Step 2. Using superglue, glue neodymium magnets measuring 2.5x5.0.12 centimeters (twelve pieces for each) to the pancakes around the entire perimeter.

Step 3. Place the pancakes opposite each other, remembering the polarity.

Step 4. Place a home-made stator between them (make 9 coils from wire with a cross-section of 0.3 centimeters, each with 70 turns). Connect the coils with an asterisk (as shown in the image), and then fill them with polymer resin. In this case, it is important that the coils are wound in one direction; you can mark the end/beginning of the winding using a colored isolette - this will be more convenient.

Step 5. The stator should be about 2 centimeters thick. The winding should come out through bolts and nuts. The distance between the rotor and stator should be 2 millimeters.

The magnets will be attracted quite strongly, and for a smooth connection it is necessary to make holes in them and cut threads for the studs. Immediately align the rotors, then use the keys to lower the upper one onto the lower one. Then you can remove the temporary pins.

Pay attention! The generator described above can be used not only for vertical, but also for horizontal windmills.

Stage five. We assemble the entire structure

First, install a special bracket on the mast, through which the stator will be attached (which, in turn, can have either three or six blades). Fix the hub above the bracket using the same nuts. Screw the finished generator onto the four studs located at the hub. After this, connect the stator to the bracket, which is fixedly fixed on the mast. Attach the turbine to the second rotor plate. Connect the stator wires to the voltage regulator using terminals.

Stage six. We install a unit that can turn wind into electricity

To install the entire wind generator with your own hands, you need to follow the steps below in the form of step-by-step instructions.

Step 1. Concrete a reliable and durable foundation in the ground.

Step 2. Pouring there concrete mortar, add the studs necessary to attach the massive hinge (all this can be easily done by hand).

Step 3. When the concrete has completely hardened, place the hinge on the studs and secure with nuts.

Step 4. Install the mast into the moving part of the hinge.

Step 5. Attach 3 or 4 guys to the top of the mast (you can use a flange or welding). You will also need a steel cable.

Step 6. Raise the mast on a hinge using one of the prepared cables (you can pull it using a car).

Step 7 The verticality of the entire mast is strictly fixed by guy wires.

Where can such a wind generator be installed?

The efficiency of its operation largely depends on how correctly you choose the place to install the wind generator. The location should be such that the system blades get as much wind as possible. The site should be open and elevated (for example, the roof of a house, but as far away from trees and other buildings as possible). Typically, the reason for this lies not only in interference, but also in the device making some noise during operation, which may not be liked by neighbors or the owners themselves.

For a more detailed understanding of the problem, we recommend that you watch the thematic video below.

Video - How to make a wind generator using a household fan

Rotary (horizontal) wind generator

Such a device can cope with providing electricity to a small house or several outbuildings. The maximum power of the wind generator will not exceed 1.5 kilowatts.

For work, prepare:

• 12 watt car generator;
• relay, battery indicator light;
• the battery itself is 12 watts;
• current converter;
• a large pan or bucket made of duralumin or stainless steel;
• a pair of clamps for attaching the generator to the mast;
• switch;
• wire, 0.4 and 0.25 centimeters;
• bolts, nuts, washers;
• voltmeter.

The tools you will need are the same as in the previous case. First, take a pan (or bucket) and, using a marker and tape measure, divide it into four equal parts. Cut out the blades, but do not cut all the way (as shown in the picture).

Make holes for the bolts in the bottom, then bend the blades, but not too much. Take into account the fact how the generator will rotate (clockwise or counterclockwise).

Next, attach the pan with the already prepared blades to the pulley, secure with bolts. Install the generator on the pre-fixed mast (use the supplied clamps for this), then connect all the cables and assemble the circuit. Rewrite the entire circuit, fix the wires on the support.

To connect the battery, use a 4mm cable with a maximum length of 1 meter. To connect the load, use a cable with a smaller cross-section. Also install an inverter. Below is an example connection diagram.

As you can see, it is quite possible to build a wind generator with your own hands. The design can be of two types, but if you have the skills and proper zeal, you can handle the work even alone. That's all, good luck!

We have developed a design for a wind generator with a vertical axis of rotation. Below, presented detailed guide on its manufacture, after reading it carefully, you can make a vertical wind generator yourself.

The wind generator turned out to be quite reliable, with low maintenance costs, inexpensive and easy to manufacture. It is not necessary to follow the list of details presented below; you can make some of your own adjustments, improve something, use something of your own, because Not everywhere you can find exactly what is on the list. We tried to use inexpensive and high-quality parts.

Materials and equipment used:

Name	Qty	Note
List of parts and materials used for the rotor:
Pre-cut sheet metal	1	Cut from 1/4" thick steel using waterjet, laser, etc. cutting
Auto hub (Hub)	1	Should contain 4 holes, about 4 inches in diameter
2" x 1" x 1/2" neodymium magnet	26	Very fragile, it is better to order additionally
1/2"-13tpi x 3" stud	1	TPI - number of threads per inch
1/2" nut	16
1/2" washer	16
1/2" grower	16
1/2".-13tpi cap nut	16
1" washer	4	In order to maintain the gap between the rotors
List of parts and materials used for the turbine:
3" x 60" Galvanized Pipe	6
ABS plastic 3/8" (1.2x1.2m)	1
Magnets for balancing	If needed	If the blades are not balanced, then magnets are attached to balance them
1/4" screw	48
1/4" washer	48
1/4" grower	48
1/4" nut	48
2" x 5/8" corners	24
1" corners	12 (optional)	If the blades do not hold their shape, you can add additional. corners
screws, nuts, washers and groovers for 1" angle	12 (optional)
List of parts and materials used for the stator:
Epoxy with hardener	2 l
1/4" stainless steel screw	3
1/4" stainless steel washer	3
1/4" stainless steel nut	3
1/4" ring tip	3	For email connections
1/2"-13tpi x 3" stainless steel stud.	1	Stainless steel steel is not ferromagnetic, so it will not “slow down” the rotor
1/2" nut	6
Fiberglass	If needed
0.51mm enamel. wire		24AWG
List of parts and materials used for installation:
1/4" x 3/4" bolt	6
1-1/4" pipe flange	1
1-1/4" galvanized pipe L-18"	1
Tools and equipment:
1/2"-13tpi x 36" stud	2	Used for jacking
1/2" bolt	8
Anemometer	If needed
1" aluminum sheet	1	For making spacers, if needed
Green paint	1	For painting plastic holders. Color is not important
Blue paint ball.	1	For painting the rotor and other parts. Color is not important
Multimeter	1
Soldering iron and solder	1
Drill	1
Hacksaw	1
Kern	1
Mask	1
Safety glasses	1
Gloves	1

Wind generators with a vertical axis of rotation are not as efficient as their horizontal counterparts, but vertical wind generators are less demanding on their installation location.

Turbine manufacturing

1. Connecting element - designed to connect the rotor to the wind generator blades.
2. The arrangement of the blades is two opposing equilateral triangles. Using this drawing, it will then be easier to position the mounting angles for the blades.

If you are not sure about something, cardboard templates will help you avoid mistakes and further rework.

The sequence of actions for manufacturing a turbine:

1. Manufacturing of the lower and upper supports (bases) of the blades. Mark and use a jigsaw to cut out a circle from ABS plastic. Then trace it and cut out the second support. You should end up with two absolutely identical circles.
2. In the center of one support, cut a hole with a diameter of 30 cm. This will be the upper support of the blades.
3. Take the hub (car hub) and mark and drill four holes on the lower support to mount the hub.
4. Make a template for the location of the blades (Fig. above) and mark on the lower support the attachment points for the corners that will connect the support and the blades.
5. Stack the blades, tie them tightly and cut them to the required length. In this design, the blades are 116 cm long. The longer the blades, the more wind energy they receive, but reverse side is unstable in strong winds.
6. Mark the blades for attaching the corners. Punch and then drill holes in them.
7. Using the blade location template shown in the picture above, attach the blades to the support using corners.

Rotor manufacturing

Sequence of actions for manufacturing a rotor:

1. Place the two rotor bases on top of each other, line up the holes and use a file or marker to make a small mark on the sides. In the future, this will help to correctly orient them relative to each other.
2. Make two paper magnet placement templates and glue them to the bases.
3. Mark the polarity of all magnets with a marker. Can be used as a "polarity tester" small magnet, wrapped in a rag or tape. By passing it over a large magnet, it will be clearly visible whether it is repelled or attracted.
4. Prepare epoxy resin(adding hardener to it). And apply it evenly from the bottom of the magnet.
5. Very carefully, bring the magnet to the edge of the rotor base and move it to your position. If a magnet is installed on top of the rotor, then the high power of the magnet can sharply magnetize it and it can break. And never put your fingers or other body parts between two magnets or a magnet and an iron. Neodymium magnets are very powerful!
6. Continue gluing the magnets to the rotor (don't forget to lubricate them with epoxy), alternating their poles. If the magnets move under the influence of magnetic force, then use a piece of wood, placing it between them for insurance.
7. Once one rotor is finished, move on to the second. Using the mark you made earlier, position the magnets exactly opposite the first rotor, but in a different polarity.
8. Place the rotors away from each other (so that they do not become magnetized, otherwise you will not be able to remove them later).

Manufacturing a stator is a very labor-intensive process. You can, of course, buy a ready-made stator (try to find them here) or a generator, but it is not a fact that they will be suitable for a specific windmill with its own individual characteristics

The wind generator stator is an electrical component consisting of 9 coils. The stator coil is shown in the photo above. The coils are divided into 3 groups, 3 coils in each group. Each coil is wound with 24AWG (0.51mm) wire and contains 320 turns. A larger number of turns, but with a thinner wire, will give a higher voltage, but lower current. Therefore, the parameters of the coils can be changed, depending on what voltage you require at the output of the wind generator. The following table will help you decide:
320 turns, 0.51 mm (24AWG) = 100V @ 120 rpm.
160 turns, 0.0508 mm (16AWG) = 48V @ 140 rpm.
60 turns, 0.0571 mm (15AWG) = 24V @ 120 rpm.

Winding reels by hand is a boring and difficult task. Therefore, to facilitate the winding process, I would advise you to make a simple device - a winding machine. Moreover, its design is quite simple and can be made from scrap materials.

The turns of all coils must be wound the same way, in the same direction, and pay attention or mark where the beginning and end of the coil are. To prevent the coils from unwinding, they are wrapped with electrical tape and coated with epoxy.

The jig is made from two pieces of plywood, a bent dowel, a piece of PVC pipe and nails. Before bending the hairpin, heat it with a torch.

A small piece of pipe between the planks provides the desired thickness, and four nails provide the required dimensions for the coils.

You can come up with your own design for a winding machine, or maybe you already have a ready-made one.
After all the coils are wound, they must be checked for identity to each other. This can be done using scales, and you also need to measure the resistance of the coils with a multimeter.

Do not connect household consumers directly from the wind generator! Also follow safety precautions when handling electricity!

Coil connection process:

1. Sand the ends of the terminals of each coil with sandpaper.
2. Connect the coils as shown in the picture above. There should be 3 groups, 3 coils in each group. With this connection diagram, three-phase alternating current will be obtained. Solder the ends of the coils or use clamps.
3. Select one of the following configurations:
   A. Configuration star". In order to obtain a large output voltage, connect terminals X,Y and Z to each other.
   B. Triangle configuration. To get a large current, connect X to B, Y to C, Z to A.
   C. To make it possible to change the configuration in the future, extend all six conductors and bring them out.
4. On a large sheet of paper, draw a diagram of the location and connection of the coils. All coils must be evenly distributed and match the location of the rotor magnets.
5. Attach the spools to the paper with tape. Prepare epoxy resin with hardener to fill the stator.
6. Use a paint brush to apply epoxy to fiberglass. If necessary, add small pieces of fiberglass. Do not fill the center of the coils to ensure sufficient cooling during operation. Try to avoid the formation of bubbles. The purpose of this operation is to secure the coils in place and flatten the stator, which will be located between the two rotors. The stator will not be a loaded unit and will not rotate.

To make it more clear, let's look at the whole process in pictures:

The finished coils are placed on wax paper with the layout diagram drawn. The three small circles in the corners in the photo above are the locations of the holes for attaching the stator bracket. The ring in the center prevents epoxy from getting into the center circle.

The coils are fixed in place. Fiberglass, in small pieces, is placed around the coils. The coil leads can be brought inside or outside the stator. Don't forget to leave enough lead length. Be sure to double-check all connections and test with a multimeter.

The stator is almost ready. Holes for mounting the bracket are drilled into the stator. When drilling holes, be careful not to hit the coil terminals. After completing the operation, trim off the excess fiberglass and, if necessary, sand the surface of the stator.

Stator bracket

The pipe for attaching the hub axle was cut to fit right size. Holes were drilled and threaded in it. In the future, bolts will be screwed into them that will hold the axle.

The figure above shows the bracket to which the stator will be attached, located between the two rotors.

The photo above shows the stud with nuts and bushing. Four of these studs provide the necessary clearance between the rotors. You can use nuts instead of a bushing larger size, or cut the washers out of aluminum yourself.

Generator. Final assembly

A small clarification: a small air gap between the rotor-stator-rotor linkage (which is set by a pin with a bushing) provides higher power output, but the risk of damage to the stator or rotor increases when the axis is misaligned, which can occur in strong winds.

The left picture below shows a rotor with 4 clearance studs and two aluminum plates (which will be removed later).
The right picture shows the assembled and painted green stator installed in place.

Build process:
1. Drill 4 holes in the upper rotor plate and tap threads for the stud. This is necessary to smoothly lower the rotor into place. Place the 4 studs against the aluminum plates glued earlier and install the upper rotor on the studs.
The rotors will be attracted to each other with very great force, which is why such a device is needed. Immediately align the rotors relative to each other according to the previously placed marks on the ends.
2-4. Alternately turning the studs with a wrench, lower the rotor evenly.
5. After the rotor rests against the bushing (providing clearance), unscrew the studs and remove the aluminum plates.
6. Install the hub (hub) and screw it on.

The generator is ready!

After installing the studs (1) and flange (2), your generator should look something like this (see picture above)

Stainless steel bolts are used to ensure electrical contact. It is convenient to use ring lugs on wires.

Cap nuts and washers are used to secure the connections. boards and blade supports for the generator. So, the wind generator is completely assembled and ready for testing.

To begin with, it is best to spin the windmill by hand and measure the parameters. If all three output terminals are short-circuited, the windmill should rotate very slowly. This can be used to stop a wind generator for service or for security reasons.

A wind generator can be used not only to provide electricity to your home. For example, this instance is made so that the stator generates a high voltage, which is then used for heating.
The generator discussed above produces 3-phase voltage with different frequencies (depending on the wind strength), and for example in Russia a single-phase network of 220-230V is used, with a fixed network frequency of 50 Hz. This does not mean that this generator is not suitable for powering household appliances. Alternating current from this generator can be converted into D.C., with fixed voltage. And direct current can already be used to power lamps, heat water, charge batteries, or a converter can be supplied to convert direct current into alternating current. But this is beyond the scope of this article.

In the picture above simple circuit bridge rectifier consisting of 6 diodes. It converts alternating current to direct current.

Wind generator installation location

The wind generator described here is mounted on a 4-meter pole on the edge of a mountain. The pipe flange, which is installed at the bottom of the generator, ensures easy and quick installation wind generator - just screw 4 bolts. Although for reliability, it is better to weld it.

Typically, horizontal wind generators “love” when the wind blows from one direction, unlike vertical wind turbines, where, due to the weather vane, they can turn and do not care about the direction of the wind. Because This wind turbine is installed on the shore of a cliff, then the wind there creates turbulent flows with different directions, which is not very effective for this design.

Another factor to consider when choosing a location is the wind strength. An archive of data on wind strength for your area can be found on the Internet, although it will be very approximate, because it all depends on the specific location.
Also, an anemometer (a device for measuring wind force) will help in choosing the location for installing a wind generator.

A little about the mechanics of a wind generator

As you know, wind arises due to the difference in temperature of the earth's surface. When the wind rotates the turbines of a wind generator, it creates three forces: lifting, braking and impulse. Lift usually occurs over a convex surface and is a consequence of pressure differences. The wind braking force arises behind the blades of the wind generator; it is undesirable and slows down the windmill. The impulse force comes from the curved shape of the blades. When air molecules push the blades from behind, they then have nowhere to go and collect behind them. As a result, they push the blades in the direction of the wind. The greater the lift and impulse forces and the less the braking force, the faster the blades will rotate. The rotor rotates accordingly, which creates a magnetic field on the stator. As a result, electrical energy is generated.

Download the magnet layout diagram.

The inexhaustible energy that air masses carry with them has always attracted the attention of people. Our great-grandfathers learned to harness the wind to the sails and wheels of windmills, after which it rushed aimlessly across the vast expanses of the Earth for two centuries.

Today I found it for him again useful work. A wind generator for a private home goes from being a technical innovation to becoming a real factor in our everyday life.

Let's take a closer look at wind power plants, evaluate the conditions for their profitable use and consider existing varieties. In our article, home craftsmen will receive information to think about on the topic of self-assembly of a windmill and the devices necessary for its efficient operation.

What is a wind generator?

The operating principle of a domestic wind power plant is simple: the air flow rotates the rotor blades mounted on the generator shaft and creates alternating current in its windings. The generated electricity is stored in batteries and used by household appliances as needed. Of course, this is a simplified diagram of how a home windmill works. In practical terms, it is complemented by devices that convert electricity.

Immediately behind the generator in the energy chain there is a controller. It converts three-phase alternating current into direct current and directs it to charge the batteries. Most household appliances cannot operate on constant power, so another device is installed behind the batteries - an inverter. It performs the reverse operation: it converts direct current into household alternating current with a voltage of 220 Volts. It is clear that these transformations do not take place without leaving a trace and take away quite a decent portion of the original energy (15-20%).

If the windmill is paired with solar battery or another electricity generator (petrol, diesel), then the circuit is supplemented with an automatic switch (ATS). When the main current source is turned off, it activates the backup one.

For maximum power wind generator should be located along the wind flow. IN simple systems The weather vane principle is implemented. To do this, a vertical blade is attached to the opposite end of the generator, turning it towards the wind.

More powerful installations have a rotating electric motor controlled by a direction sensor.

Main types of wind generators and their features

There are two types of wind generators:

1. With a horizontal rotor.
2. With vertical rotor.

The first type is the most common. It is characterized high efficiency(40-50%), but has increased level noise and vibration. In addition, its installation requires a large free space (100 meters) or a high mast (from 6 meters).

Generators with a vertical rotor are less energetically efficient (the efficiency is almost 3 times lower than that of horizontal ones).

Their advantages include simple installation and reliable design. Low noise makes it possible to install vertical generators on the roofs of houses and even at ground level. These installations are not afraid of icing and hurricanes. They are launched from a weak wind (from 1.0-2.0 m/s) while a horizontal windmill needs an air flow of medium strength (3.5 m/s and above). Vertical wind generators are very diverse in the shape of the impeller (rotor).

Rotor wheels of vertical wind turbines

Due to the low rotor speed (up to 200 rpm), the mechanical life of such installations significantly exceeds those of horizontal wind generators.

How to calculate and select a wind generator?

The wind is not natural gas, pumped through pipes and not electricity, uninterruptedly supplied through wires to our house. He is capricious and fickle. Today a hurricane tears off roofs and breaks trees, and tomorrow it gives way to complete calm. Therefore, before purchasing or self-production wind turbine, you need to assess the potential of air energy in your area. To do this, the average annual wind force must be determined. This value can be found on the Internet by request.

Having received such a table, we find the area of ​​​​our residence and look at the intensity of its color, comparing it with the rating scale. If the average annual wind speed is less than 4.0 meters per second, then there is no point in installing a windmill. It will not provide the required amount of energy.

If the wind strength is sufficient to install a wind power plant, then you can proceed to the next step: selecting the generator power.

If we are talking about autonomous energy supply at home, then the average statistical electricity consumption of 1 family is taken into account. It ranges from 100 to 300 kWh per month. In regions with low annual wind potential (5-8 m/sec), a wind turbine with a power of 2-3 kW can generate this amount of electricity. It should be taken into account that in winter the average wind speed is higher, so energy production during this period will be greater than in summer.

Selecting a wind generator. Approximate prices

Prices for vertical domestic wind generators with a capacity of 1.5-2.0 kW are in the range from 90 to 110 thousand rubles. The package at this price includes only a generator with blades, without a mast and additional equipment (controller, inverter, cable, batteries). A complete power plant including installation will cost 40-60% more.

The cost of more powerful wind turbines (3-5 kW) ranges from 350 to 450 thousand rubles (with additional equipment and installation work).

DIY windmill. Fun or real savings?

Let’s say right away that making a wind generator with your own hands that is complete and effective is not easy. Proper calculation of the wind wheel, transmission mechanism, selection of a generator suitable for power and speed is a separate topic. We will give only brief recommendations on the main stages of this process.

Generator

Automotive generators and electric motors from washing machines with direct drive are not suitable for this purpose. They are capable of generating energy from the wind wheel, but it will be insignificant. To operate efficiently, self-generators need very high speeds, which a windmill cannot develop.

Motors for washing machines have another problem. There are ferrite magnets there, but the wind generator needs more efficient ones - neodymium ones. Process them self-installation and winding current-carrying windings requires patience and high precision.

The power of a device assembled by yourself, as a rule, does not exceed 100-200 watts.

Recently, motor-wheels for bicycles and scooters have become popular among DIYers. From a wind energy standpoint, these are powerful neodymium generators, optimally suited for working with vertical wind wheels and charging batteries. From such a generator you can extract up to 1 kW of wind energy.

Motor-wheel - a ready-made generator for a homemade wind power plant

Screw

The easiest to manufacture are sail and rotor propellers. The first consists of lightweight curved tubes mounted on a central plate. Blades made of durable fabric are pulled over each tube. The large windage of the propeller requires hinged fastening of the blades so that during a hurricane they fold and do not become deformed.

The rotary wind wheel design is used for vertical generators. It is easy to manufacture and reliable in operation.

Homemade wind generators with a horizontal axis of rotation are powered by a propeller. Home craftsmen collect it from PVC pipes diameter 160-250 mm. The blades are mounted on a round steel plate with a mounting hole for the generator shaft.