Assembling a homemade wind turbine: design options from FORUMHOUSE users. DIY vertical windmill (5 kW) Wind generator

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

Today, a useful job has been found for him again. A wind generator for a private house from the category of technical innovations is becoming a real factor in our life.

Let's take a closer look at wind farms, evaluate the conditions for their cost-effective use and consider the existing varieties. Home craftsmen will receive in our article information for reflection on the topic of self-assembly of a windmill and the devices necessary for its effective operation.

What is a wind generator?

The principle of operation of a household wind farm is simple: the air flow rotates the rotor blades mounted on the generator shaft and creates alternating current in its windings. The resulting electricity is stored in batteries and used as needed by household appliances. Of course, this is a simplified scheme for the operation of a home windmill. In practical terms, it is complemented by devices that convert electricity.

Immediately behind the generator in the energy chain is the controller. It converts three-phase alternating current into direct current and directs it to charge batteries. Most household appliances cannot work on a “permanent” basis, so another device is placed behind the batteries - an inverter. It performs the reverse operation: it turns direct current into household alternating voltage of 220 volts. It is clear that these transformations do not pass without a trace and take a fairly decent part (15-20%) from the initial energy.

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

To obtain maximum power, the wind generator must be located along the wind flow. In simple systems, the principle of a weather vane is implemented. To do this, a vertical blade is fixed at the opposite end of the generator, turning it towards the wind.

In more powerful installations, there is a rotary electric motor controlled by a direction sensor.

The main types of wind turbines and their features

There are two types of wind generators:

With a horizontal arrangement of a rotor.
With vertical rotor.

The first type is the most common. It is characterized by high efficiency (40-50%), but has an increased level of 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 energy efficient (the efficiency is almost 3 times lower than that of horizontal ones).

Their advantages include simple installation and reliable design. Low noise level allows you 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). According to the shape of the impeller (rotor), vertical wind turbines are very diverse.

Rotary wheels of vertical windmills

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

How to calculate and choose a wind generator?

Wind is not natural gas pumped through pipes, nor is it electric power flowing uninterruptedly through wires to our homes. He is capricious and fickle. Today a hurricane tears off roofs and breaks trees, and tomorrow it is replaced by complete calm. Therefore, before buying or self-manufacturing a windmill, you need to assess the potential of air energy in your area. To do this, determine the average annual wind force. This value can be found on the Internet upon request.

Having received just such a table, we find the area of \u200b\u200bour 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 wind turbine. It will not provide the required amount of energy.

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

If we are talking about autonomous power supply at home, then the average statistical consumption of electricity by 1 family is taken into account. It is in the range from 100 to 300 kWh per month. In regions with a low annual wind potential (5-8 m/s), such an amount of electricity can be generated by a 2-3 kW windmill. 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.

The choice of wind generator. Estimated prices

Prices for vertical domestic wind turbines 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, together with 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).

Windmill with your own hands. Fun or real savings?

Let's say right away that it is not easy to make a wind generator with your own hands full-fledged and efficient. Proper calculation of the wind wheel, transmission mechanism, selection of a suitable generator in terms of power and speed is a separate issue. We will give only brief recommendations on the main stages of this process.

Generator

Automotive alternators and electric motors from direct drive washing machines are not suitable for this purpose. They are able to generate energy from the wind wheel, but it will be negligible. For efficient operation, autogenerators need very high speeds that a windmill cannot develop.

Washer motors have a different problem. There are ferrite magnets, and for a wind generator, more productive ones are needed - neodymium. The process of their self-assembly and winding of current-carrying windings requires patience and high accuracy.

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

Recently, motor-wheels for bicycles and scooters have been popular among home-made people. From the standpoint of wind energy, these are powerful neodymium generators, optimally suited for working with vertical wind wheels and charging batteries. Up to 1 kW of wind energy can be removed from such a generator.

Motor-wheel - a ready-made generator for a homemade wind farm

Screw

Sailing and rotary propellers are the easiest to make. The first consists of light, curved tubes mounted on a central plate. Blades made of durable fabric are pulled onto each tube. The large windage of the propeller requires hinged fastening of the blades so that during a hurricane they fold and do not deform.

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

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

In recent years, the topic of green energy has become extremely popular. Some even predict that such energy will completely replace coal, gas, and nuclear power plants in the near future. One of the areas of green energy is wind energy. Generators that convert wind energy into electricity are not only industrial, as part of wind farms, but also small ones that serve private households.

You can even make a wind generator with your own hands - this is what this material is dedicated to.

What is a generator

In a broad sense, a generator is a device that produces any products or converts one type of energy into another. It can be, for example, a steam generator (produces steam), an oxygen generator, a quantum generator (source of electromagnetic radiation).
But within the framework of this topic, we are interested in power generators. This name refers to devices that convert various types of non-electric energy into electricity.

Types of generators

Electric generators are classified as:

In addition, electromechanical generators are classified according to the type of engine. The following types are distinguished:

turbogenerators are driven by a steam turbine;
hydro generators use a hydraulic turbine as an engine;
diesel generators or gasoline generators are made on the basis of diesel or gasoline engines;
wind turbines convert the energy of the air masses into electricity using a wind turbine.

Let's take a closer look at wind turbines (they are also called wind turbines). The simplest low-power wind generator usually consists of a mast, usually reinforced with guy wires, on which the wind turbine is mounted.

This wind turbine is spun by a screw that drives the rotor of an electric generator. The structure of the device, in addition to the generator, also includes a battery with a charge controller and an inverter connected to the mains.

Did you know? By 2016, the total capacity of all wind turbines in the world was 432 GW. Thus, wind energy has surpassed nuclear energy in terms of power.

The scheme of operation of this device is quite simple: under the action of the wind, the screw rotates, spinning the rotor, the electric generator generates an alternating electric current, which is converted by the charge controller into direct current.
This current charges the battery. The direct current from the battery is converted by the inverter into alternating current, the parameters of which correspond to the parameters of the mains.

Industrial devices are mounted on towers. They are additionally equipped with a rotary mechanism, an anemometer (a device for measuring wind speed and direction), a device for changing the angle of rotation of the blades, a braking system, a power cabinet with control circuits, fire extinguishing and lightning protection systems, a system for transmitting data on the operation of the installation, etc.

According to the location of the axis of rotation relative to the earth's surface, wind turbines are divided into vertical and horizontal. The simplest vertical model is the Savonius rotor.

It has two or more blades, which are hollow semi-cylinders (cylinders cut in half vertically).
Savonius rotor There are various options for the layout and design of these blades: symmetrically fixed, overlapping edges, with an aerodynamic profile.

The advantage of the Savonius rotor is the simplicity and reliability of the design, in addition, its operation does not depend on the direction of the wind, the disadvantage is low efficiency (no more than 15%).

Did you know? Windmills appeared around 200 BC. e. in Persia (Iran). They were used to make flour from grain. In Europe, such mills appeared only in the XIII century.

Another vertical design is the Darrieus rotor.. Its blades are wings with an aerodynamic profile. They can be arcuate, H-shaped, spiral. Blades can be two or more.
Rotor Daria The advantages of such a wind generator are:

its high efficiency
reduced noise during operation,
relatively simple design.

Among the shortcomings are noted:

high load on the mast (due to the Magnus effect);
the absence of a mathematical model of the operation of this rotor, which makes it difficult to improve;
rapid wear due to centrifugal loads.

Another type of vertical installation is the helicoid rotor.. It is equipped with blades that are twisted along the bearing axis.
Helicoid rotor This ensures the durability of the structure and high efficiency. The disadvantage is the high cost due to the complexity of manufacturing.

The multi-blade type of windmill is a design with two rows of vertical blades - external and internal. This design gives the highest efficiency, but is expensive.

Horizontal models are different:

the number of blades (single-blade and with a large number);
the material from which the blades are made (rigid or flexible sailing);
variable or fixed pitch blades.

Structurally, they are all similar. In general, wind turbines of this type are characterized by high efficiency, but they need constant adjustment to the direction of the wind, which is solved by using a weather vane in the design or by automatically positioning the installation using a rotary mechanism according to the sensor readings.

DIY wind generator

The choice of wind turbine models on the market is the widest, devices of various designs and various capacities are available. But a simple installation can be done by yourself.

As a generator, it is recommended to take a three-phase one with permanent magnets, for example, a tractor one. But you can make it from an electric motor, which will be discussed in more detail below. The choice of blades is important. If the windmill is of a vertical type, variations of the Savonius rotor are usually used.
Tractor generator For the manufacture of blades, a cylindrical container, for example, an old boil-out, is quite suitable. But, as mentioned above, wind turbines of this type have low efficiency, and it is unlikely that it will be possible to make blades of a more complex shape for a vertical windmill. In homemade products, four semi-cylindrical blades are usually used.

As for horizontal wind turbines, a single-bladed design is optimal for a low-power installation, however, for all its apparent simplicity, it will be extremely difficult to make a balanced blade in a handicraft way, and without this, the windmill will often fail.

Important! You should not get carried away with a large number of blades, because during operation they can form a so-called “air cap”, due to which the air will go around the windmill, and not pass through it. For home-made devices of the horizontal type, three vane-type blades are considered optimal.

Two types of blades can be used in horizontal windmills: sail and vane. Sailing is very simple, it's just wide strips that look like windmill blades. The disadvantage of such elements is a very low efficiency. In this regard, winged blades are much more promising. At home, they are usually made from 160 mm PVC pipes according to the pattern.

You can also use aluminum, but it will cost much more. In addition, a PVC pipe product initially has a bend, which gives it additional aerodynamic properties.
PVC pipe blades The length of the blades is selected according to the following principle: the more powerful the output power of the windmill, the longer they are; the more there are, the shorter they are. For example, for a three-bladed 10 W windmill, the optimal length is 1.6 meters, for a four-bladed windmill - 1.4 m.

If the power is 20 W, then the indicator will change to 2.3 m for a three-blade and 2 m for a four-blade.

The main stages of manufacture

Below is an example of self-manufacturing of a horizontal three-blade installation with conversion into an asynchronous motor generator from a washing machine.

Getting electrical energy with the help of wind is becoming one of the latest fashion trends. A household wind generator, which belongs to the technical means of alternative electric power industry, has gained its popularity quite deservedly, since turning to it provides the owner with a number of advantages:

wind energy refers to environmentally friendly means of generating electricity, no waste generation;
easy to use due to its high reliability and low operating costs;
can be assembled independently with minimal skills in the field of construction and electrics;
its attractiveness will only increase over time due to the inevitable increase in tariffs of power supply companies.

Device and principle of operation

Any wind generator consists of several typical enlarged blocks. The unit necessarily contains a turbine that rotates under the action of an air flow, directly or most often through a step-up gearbox, transmits the generated torque to the shaft of an electric generator. The rotor rotates inside the stator based on neodymium magnets, as a result of which electrical energy is generated.

The design of a small power wind generator is shown in Figure 1.

Rice. 1. The design of a homemade wind generator

The electrical energy generated by the wind generator enters the intermediate storage, the functions of which are usually taken over by the battery. The current supplied by the battery feeds the inverter, from the output of which the normal 220-volt alternating voltage of the household frequency is removed.

The presence of a battery is mandatory, because. it allows you to smooth out fluctuations in the power taken from the turbine. A role in this is played by the fact that a household wind generator operates stably at wind speeds of 6 m/s and higher, while the average annual value of this parameter in most of Russia is about one and a half times lower.

The necessary switching, adjustments and other functions are implemented by the automation unit.

An appropriate level of operational reliability is achieved if the structure has reserves for the output power (usually 10 - 20%).

Types of windmills

The main difference between wind generators is the design of an air turbine, which can have a different design. Usually, the complete set of units according to the orientation of the turbine rotation shaft is divided into two main varieties: vertical and horizontal.

vertical

A distinctive feature and the main advantage of the vertical wind generator unit is the absence of strict requirements for the height of its installation, which greatly simplifies the choice of installation site, the installation process, and the subsequent maintenance of mechanically moving parts. The air turbine belongs to the low-speed variety of this technique, it can be performed as

the simplest classical rotor with a minimum of three vertically oriented blades (an example of such a device is shown in Figure 2);
double-row rotor, the presence of an internal row of adjustable blades provides it with increased efficiency)
rotor Daria;
Savonius rotor;
helical rotor.

The more complex shape of the last three types of turbines provides them with a lower material consumption.

Figure 2. Rotary wind turbine of a vertical wind turbine

It features a minimum of moving parts, the efficiency of the installation depends little on the direction of the wind.

Horizontal

Wind generators with a horizontal orientation of the turbine shaft are driven by a propeller. The propeller can be two-, three- and multi-bladed. The blades of some propellers are sometimes given a rather complex shape to slightly increase the efficiency of the installation. An example of such a unit is shown in Figure 3.

Rice. 3. Horizontal multi-blade wind generator

Due to the large diameter of the propellers, they are usually mounted on a steel tubular or lattice mast at a height of up to several tens of meters. Examples of such masts are shown in Figure 4 and Figure 5. The downside of increasing the height of the installation is the reduction of turbulence in the air flow due to the weakening of the influence of the earth, i.e. increase in efficiency and generated power. Taking into account this feature, it is not recommended to use windmills of this design for cottage settlements due to the strong shielding effect of neighboring buildings.

Figure 4. Truss mast for installation of a horizontal wind turbine

Rice. 5. Mounting unit for tubular mast

To create a torque balance, the generator is closed with a shaft fairing so that it acts as a propeller counterweight. The additionally extended body design facilitates its “downstream” orientation.

Compared to a vertical device, it allows you to remove more power. The price for this is the difficulty in choosing the installation site, the complexity of installation, ongoing maintenance, as well as unpleasant acoustic noise during operation. In addition, due to the high height of the structure, horizontal wind generators necessarily require lightning protection.

Small wind turbines

Small or household wind turbines usually include units with a power of not more than 5 kW. In retail sales, units of various capacities and designs of domestic and foreign production are available, which allows you to choose the right device without overpaying.

Typically, units are supplied in a minimum kit, which:

includes controller;
does not contain a buffer battery;
allows assembly of the unit at the installation site, provided there are no local restrictions.

Due to their technical complexity, the installation project for horizontal devices requires careful study, specialist advice may be required.

The cost of low-power models starts from several tens of thousands of rubles, it strongly depends on the output power.

Automation of wind farms

Modern electric wind turbines are equipped with an advanced automation system, which:

significantly improves performance;
provides equalization of the output power;
makes operation safe.

A typical set of automation includes:

wind wheel speed limiter at high wind speeds;
wheel alignment “downstream” (important for horizontal windmills);
short circuit protection;
shutdown in case of equipment failures, hurricane winds, exceeding the threshold level of vibration.

Models of the middle and senior classes necessarily support remote control and diagnostics. Some of the units additionally control the direction and strength of the air flow to maximize the output power by choosing the appropriate installation angle of the entire device and turbine blades.

braking system

The braking system prevents mechanical destruction of the unit when the wind speed is too high. The essence of this system is that the automation closes the electrical circuits of the magnetic system of the generator, which leads to the appearance of a powerful braking force.

Additionally, the control system operation algorithm provides for a complete shutdown of the air turbine during hurricane-force winds. The stop threshold can be adjusted by the user, typical factory settings of this parameter assume the activation of the stop mode at a speed of 80 km/h.

Manufacturers

Domestic industry has launched serial production of a wide range of domestic wind turbines. Their parameters are shown in the table:

Model	Manufacturer	Type of	Power	Note
VG 0.25	Vetro Svet, Russia	G	250 W	—
VEU-3(4)	SKB Iskra, Russia	AT	3 kW	4-blade model
Series L	Wind power, Russia	AT	0.8 - 10 kW	—
RKraft	Germany	G	0.5 - 5 kW	—
Wind Generator M300	China	AT	100 - 270 W	6-bladed rotor with a diameter of 1 m, weight 11 kg, does not have a controller
Condor Home	EDS Group, Russia	G	500 W	3-bladed fiberglass rotor Maximum wind speed 25 m/s Weight 56 kg

Note: D - horizontal, V - vertical

Pros and cons

The main advantage of wind farms is their autonomy.

The main technical disadvantages of this type of equipment are dependence on the weather (in addition to wind strength, snow and rain also affect) and relatively low power, the value of which on average does not exceed several hundred watts. Require the mandatory use of an intermediate buffer battery, which requires replacement after several years of service.

When compared with diesel generators, they are inferior to them in terms of the duration of operation, but they do not require the delivery of fuel and the implementation of complex and expensive fire safety measures for its storage.

Which in the middle latitudes actually work for a maximum of five months, is noticeably superior to those that function all year round.

At existing electricity tariffs, they do not provide a significant gain in terms of the reduced costs, but they do not turn out to be unprofitable.

Manufacturers of wind farms pay great attention to their external design. So the presence of this unit in a suburban area not only indicates the “technical advancement” of its owner, but can also become an important design element and a clear demonstration of concern for the environment.

The aesthetic parameters can be judged from Figure 6.

Rice. 6. Horizontal wind turbine Condor Home of domestic production

Conclusion.

Wind power plants can be considered a full-fledged alternative source of electrical energy. Taking into account the typical climatic conditions of most areas of our country, it makes sense to combine small wind turbines into a single system with a solar battery and a diesel generator. In this case, they may well become an effective autonomous auxiliary means of generating electricity in a country house or a country house.

Often situations arise when electricity in the nearest transmission line becomes unavailable or unreasonably expensive, and in such cases only a homemade windmill can help out. Let's look at the options for autonomous supply of a country house with electricity.

Wind generators - which model is better?

Very often you want to save on electricity or get it where there are no power transmission towers yet. It is also possible that it is simply not possible to connect to this tower due to the lack of free power. In any of these cases, it becomes necessary to find an affordable source of electricity, preferably renewable, that is, without the use of fuel. Therefore, let's forget for a while about the existence of gasoline and diesel generators and try to use the power of the wind to generate electricity.

Windmills have existed for quite a long time, a couple of centuries ago windmills were actively used. Yes, during a calm, such a device is of little use, and during a storm even the most reliable mechanism can fail (at best). But for all its unreliability, a do-it-yourself wind generator for a home is the easiest to make, it is considered the most effective, especially if there is no access to a fast-flowing river to install the wheel. And it should be remembered that the windmill tower should not interfere with neighbors with noise, vibration, or even a cast shadow, according to the rules for building a residential building on the site.

There are only 2 main types of windmills: with a vertical and horizontal axis of rotation. Mills, once used everywhere, were machines whose blades were mounted on a horizontally oriented axis. Also, most windmills today are made according to this principle, since this option provides the greatest efficiency. However, do-it-yourself vertical axis wind turbines for home use the lightest wind that will not move the blades of the propeller models. Light gusts from 1-2 meters per second are enough for them. As for manufacturing, it is much easier to make a vertical windmill that receives wind from any direction.

Generators are also distinguished by the type of blades that both of the above species have. For the most part, the main factor in the division into types is the design: rigid or sail. Already, depending on which option is preferable for a particular model, the material for the manufacture of the blades of the wind flow catcher is selected. It can be plywood, tin or thin sheet steel, plastic, composite - for a light rigid structure, and any flexible but durable material will do for a sailboat, including silk, banner fabric or even a thin tarpaulin.

Differences in the shape of the blades of the generators - comparison of efficiency

The simplest version of the horizontal type is the sail structure, that is, simply the arrangement of the propeller planes at a slight angle to the plane of rotation. Rigid blades will require an accurate calculation of the bending of their surfaces, or it will be necessary to achieve maximum performance empirically. Insufficient curvature of the "wing" will result in a decrease in efficiency due to poor capture of the air flow, and too much curvature itself will create resistance to rotation due to friction against the air.

As for vertical axis generators, their wind catchers come in a wide variety of shapes, and development of new contours and curves is ongoing. The simplest option is with blades in the form of troughs, the so-called Savonius design. Their number is usually made even - 2 or 4. Although it happens more when they make home-made 30 kW multi-bladed vertical wind turbines with additional static screens on the outer ring. These screens direct and concentrate the wind to certain areas of the rotor located inside the ring, where the blades are installed directly. They, depending on the diameter of the base disk, can be read from 8 to 16 pieces.

There are also orthogonal propellers, which are located on vertically mounted axes and rotate in a horizontal plane, but their main drawback is their extremely low efficiency. Also, such generators do not work with weak gusts of wind, a speed of at least 4 meters per second is needed. And the least commonly used models of Dorier windmills, including helicoid, with a helical bend of the blades, arcuate wind traps and a design of the "H" type. They are reliable and effective, but they are difficult to make at home.

Pros and cons of various types - analyze and evaluate

As already mentioned, the performance is much higher for models with a horizontal axis of rotation. However, they need a strong wind, this usually happens at a height of more than 10-15 meters, and it is this length that the mast is installed, which is crowned with a rotary gondola with blades. Another positive quality can be considered the absence of a bending load on the shaft, which occurs in windmills with a vertical axis. The disadvantages include the fact that rotary propeller models have 2 shafts, which means more wear parts and a higher probability of breakage.

As for vertical systems, their advantages and disadvantages depend on the model. For example, Savonius windmills are the simplest and can be made for the home with your own hands, both from a tin can and from a metal or plastic barrel. They start up in the presence of 4 blades from the lightest breath of the wind, especially if high-quality parts are installed, then self-unwinding will occur due to inertia even with a gusty wind. But if there are only 2 or 3 blades, independent rotation is impossible, so they put 2 such modules one on top of the other, placing the wind catchers of each at an angle of 90 degrees relative to the other. The windage of this type is large, and therefore the lateral pressure on the axle is very high during a strong storm.

Orthogonal windmills, in addition to their low power, have a number of disadvantages. Firstly, this is a rather strong vibration due to uneven pressure on different parts of the wing-shaped blade. As a result, a bearing mounted on a vertical shaft quickly deteriorates. In addition, such generators emit a rather strong and unpleasant noise during rotation, and therefore can cause dissatisfaction with neighbors in the nearest areas. Helicoid, if purchased ready-made, factory-assembled, are very expensive, as well as multi-blade designs, which have a very large number of parts.

Any wind generator can be installed in a rotating pipe to increase efficiency.

The principle of operation of windmills - how is the system arranged?

Regardless of the type of windmill, it cannot generate energy by itself, it needs a generator, the rotation of the shaft of which will be provided by the blades. If you have a design with a horizontal axis of rotation, you will need a gearbox to transmit movement to the shaft. Next, a controller is connected, which converts the electricity received on the generator coils into direct current, which then enters the batteries. Next, you can connect an LED light bulb, but if you want to charge a device or connect a laptop, you will also need an inverter that converts the charge stored in the battery into alternating current.

It should be borne in mind that each change in current from alternating to direct, and vice versa, reduces the total amount of energy by 10–15%.

A vertical axis installation is convenient in that its shaft can be quite long, and this allows you to place the generator at the bottom of the mast, that is, in the direct access zone. Often, an automatic switch is installed in the circuit, in cases where the windmill works in combination with solar panels or a water wheel. Also, in some models, they put a brake, which is needed in case the battery is fully charged. Hinges can be provided on the blades of windmills with a horizontal axis of rotation, which fold the wind catchers during a storm. A very powerful do-it-yourself 5 kilowatt wind generator is sometimes supplemented by a rotary electric motor, which is triggered by an air flow direction sensor.

Product on neodymium magnets - brief instructions

It is better to entrust the assembly of the rotor and stator for a windmill to a specialist, but if you decide to make a windmill for a private house from scratch with your own hands, you need to know how the generator is made. You should start with the base, for which it is best to use the hub of the car, since it already has bearings. Neodymium magnets are glued onto the disk at regular intervals, the poles of which, facing you, must alternate. Moreover, in a single-phase model, the number of opposite-pole sides must match. As for three-phase generators, it is recommended to observe proportions of 2:3 or 3:4.

Next, you should start winding the coils for the stator. It is also better to entrust this task to a specialist or use special devices that will help to cope with the task more accurately than if everything is done manually. In order to successfully charge a 12 watt battery, you need a total number of turns in all coils equal to 1000. In general, the simplest formula can be used to calculate the turns ω=44/(T*S), where 44 is a constant factor, T is the Tesla induction, and S is the cross section of the wire in square centimeters. Tesla induction is determined from the table for various types of conductors:

Wound coils (it is better to give them a rectangular or trapezoidal shape for ease of arrangement in a circle) are fixed with glue on a fixed base of the stator. In this case, the shape and dimensions of the internal space of the coil must correspond to the contours of the magnet. The same goes for thickness. We bring out all the ends of the conductors and connect them so that we get two common bundles "+" and "-". We fill the cores of the coils with the same glue that was used for fixing, it is also possible to completely isolate the wires laid on the stator disk with it. Now, if the magnets are combined with the coils during the rotation of the rotor, the potential difference between the poles will create conditions for generating electricity.

Making a windmill based on a finished electric motor

Usually, home craftsmen try to use car generators, but not all are suitable, but only self-excited ones, for example, those used in some tractor models. Most require the presence of a connected battery for the current to appear. However, a motor-wheel for a scooter or scooter can also be used as the basis for a windmill. This will make it possible to make low-noise vertical wind turbines of 5 kW, which will have a very high resource due to the simplest design with a minimum of parts.

You can also use almost any electric motor from household machines as a generator, the main thing is that there are no brushes in the base, as, for example, in or electric drills - such generators will not suit you. A cooler from a computer is also suitable for a low-power version, but only for charging small electronic devices. If you want to get a do-it-yourself vertical wind generator, at least 2 kW, it is better to take the motor from a powerful fan as a basis.

One of the most affordable renewable energy options is the use of wind energy. For information on how to independently calculate, assemble and install a windmill, read this article.

Classification of wind generators

Installations are classified based on the following wind turbine criteria:

location of the axis of rotation;
number of blades;
element material;
screw pitch.

Wind turbines, as a rule, have a design with a horizontal and vertical axis of rotation.

Execution with a horizontal axis - a propeller design with one, two, three or more blades. This is the most common version of air power plants due to its high efficiency.

Vertical axis design - orthogonal and carousel designs on the example of Darrieus and Savonius rotors. The last two concepts should be clarified, since both have a certain significance in the design of wind generators.

The Darrieus rotor is an orthogonal design of a wind turbine, where aerodynamic blades (two or more) are located symmetrically to each other at a certain distance and are mounted on radial beams. A fairly complex version of a wind turbine that requires careful aerodynamic design of the blades.

The Savonius rotor is a carousel-type wind turbine design, where two semi-cylindrical blades are located one against the other, forming a sinusoidal shape as a whole. The efficiency of the structures is low (about 15%), but can be almost doubled if the blades are placed in the direction of the wave not horizontally, but vertically and a multi-tiered version is used with an angular displacement of each pair of blades relative to other pairs.

Advantages and disadvantages of "windmills"

The advantages of these devices are obvious, especially in relation to domestic operating conditions. Users of "windmills" actually get the opportunity to reproduce free electrical energy, except for small costs for construction and maintenance. However, the disadvantages of wind turbines are also obvious.

So, in order to achieve efficient operation of the installation, it is required to fulfill the conditions for the stability of wind flows. Man cannot create such conditions. This is purely the prerogative of nature. Another, but already a technical drawback, is the low quality of the generated electricity, as a result of which it is necessary to supplement the system with expensive electrical modules (multipliers, chargers, batteries, converters, stabilizers).

Advantages and disadvantages in terms of the features of each of the modifications of wind turbines, perhaps, balance at zero. If horizontal-axis modifications are characterized by a high efficiency value, then for stable operation they require the use of wind flow direction controllers and hurricane wind protection devices. Vertical-axis modifications have low efficiency, but work stably without a wind direction tracking mechanism. At the same time, such wind turbines are distinguished by a low level of noise, eliminate the effect of "spreading" in conditions of strong winds, and are quite compact.

Homemade wind generators

Making a "windmill" with your own hands is a completely solvable task. Moreover, a constructive and rational approach to business will help to minimize the inevitable financial costs. First of all, it is worth sketching out the project, carrying out the necessary calculations of balancing and power. These actions will not only be the key to the successful construction of a wind farm, but also the key to maintaining the integrity of all purchased equipment.

It is recommended to start with the construction of a micro-windmill with a power of several tens of watts. In the future, the experience gained will help create a more powerful design. When creating a home wind generator, you should not focus on obtaining high-quality electricity (220 V, 50 Hz), since this option will require significant financial investments. It is wiser to limit ourselves to using the initially received electricity, which can be successfully used without conversion for other purposes, for example, to support heating and hot water systems built on electric heaters (heaters) - such devices do not require a stable voltage and frequency. This makes it possible to create a simple circuit that runs directly from the generator.

Most likely, no one will argue that heating and hot water supply in the house are inferior in importance to household appliances and lighting fixtures, for which power is often sought to install home windmills. The device of a wind turbine specifically for the purpose of providing the house with heat and hot water is the minimum cost and simplicity of design.

Generalized project of a home wind turbine

Structurally, a home project largely repeats an industrial installation. True, household solutions are often based on vertical-axis wind turbines and are equipped with low-voltage DC generators. The composition of household wind turbine modules, subject to the receipt of high-quality electricity (220 V, 50 Hz):

wind turbine;
wind orientation device;
multiplier;
DC generator (12 V, 24 V);
battery charge module;
rechargeable batteries (lithium-ion, lithium-polymer, lead-acid);
DC voltage converter 12 V (24 V) to AC voltage 220 V.

Wind turbine PIC 8-6/2.5

How it works? Just. The wind turns the windmill. The torque is transmitted through the multiplier to the shaft of the DC generator. The energy received at the output of the generator through the charging module is accumulated in the batteries. From the battery terminals, a constant voltage of 12 V (24 V, 48 V) is supplied to the converter, where it is transformed into a voltage suitable for powering household electrical networks.

About generators for home "windmills"

Most residential wind turbine designs are typically constructed using low-speed DC motors. This is the simplest version of the generator that does not require modernization. Optimally - electric motors with permanent magnets, designed for a supply voltage of the order of 60-100 volts. There is a practice of using car generators, but for such a case, the introduction of a multiplier is required, since autogenerators produce the required voltage only at high (1800-2500) revolutions. One of the possible options is the reconstruction of an AC induction motor, but it is also quite complicated, requiring precise calculations, turning, installation of neodymium magnets in the rotor area. There is an option for a three-phase asynchronous motor with the connection of capacitors of the same capacity between the phases. Finally, there is the possibility of making a generator from scratch with your own hands. There are a lot of instructions for this.

Vertical-axis homemade "windmill"

A fairly efficient and, most importantly, inexpensive wind generator can be built on the basis of the Savonius rotor. Here, as an example, a micro-power plant is considered, the power of which does not exceed 20 W. However, this device is quite sufficient, for example, to provide electrical energy to some household appliances operating on a voltage of 12 volts.

Parts set:

Aluminum sheet 1.5-2 mm thick.
Plastic pipe: diameter 125 mm, length 3000 mm.
Aluminum pipe: diameter 32 mm, length 500 mm.
DC motor (potential generator), 30-60V, 360-450 rpm, for example, PIK8-6/2.5 electric motor.
Voltage controller.
Battery.

Making a Savonius rotor

Three "pancakes" with a diameter of 285 mm are cut out of an aluminum sheet. Holes are drilled in the center of each for a 32 mm aluminum pipe. It turns out something similar to CDs. Two pieces 150 mm long are cut from the plastic pipe and cut in half lengthwise. The result is four semicircular blades 125x150 mm. All three aluminum "CDs" are put on a 32 mm pipe and fixed at a distance of 320, 170, 20 mm from the top point strictly horizontally, forming two tiers. Blades are inserted between the discs, two per tier and fixed strictly one against the other, forming a sinusoid. In this case, the blades of the upper tier are displaced relative to the blades of the lower tier by an angle of 90 degrees. The result is a four-bladed Savonius rotor. For fastening elements, you can use rivets, self-tapping screws, corners, or use other methods.

Connecting to the engine and mounting on the mast

The shaft of DC motors with the above parameters usually has a diameter of no more than 10-12 mm. In order to connect the motor shaft to the wind turbine pipe, a brass bushing is pressed into the lower part of the pipe, having the required inner diameter. A hole is drilled through the wall of the pipe and the sleeve, a thread is cut to screw in the locking screw. Next, the wind turbine pipe is put on the generator shaft, after which the connection is rigidly fixed with a locking screw.

The rest of the plastic pipe (2800 mm) is the mast of the wind turbine. The generator assembly with the Savonius wheel is mounted at the top of the mast - it is simply inserted into the pipe until it stops. As a stop, a metal disk cover is used, fixed on the front end of the motor, having a diameter slightly larger than the diameter of the mast. Holes are drilled on the periphery of the lid for attaching braces. Since the diameter of the motor housing is smaller than the inner diameter of the pipe, gaskets or stops are used to align the generator in the center. The cable from the generator is passed inside the pipe and out through the window at the bottom. During installation, it is necessary to take into account the design of the generator protection against moisture, using sealing gaskets for this. Again, in order to protect against precipitation, an umbrella cap can be installed above the connection of the wind turbine pipe with the generator shaft.

Installation of the entire structure is carried out in an open, well-ventilated area. A hole 0.5 meters deep is dug under the mast, the lower part of the pipe is lowered into the hole, the structure is leveled with stretch marks, after which the hole is filled with concrete.

Voltage controller (simple charger)

A manufactured wind generator, as a rule, is not capable of delivering a voltage of 12 volts due to the low speed. The maximum frequency of rotation of the wind turbine at a wind speed of 6-8 m / s. reaches a value of 200-250 rpm. At the output, it is possible to obtain a voltage of the order of 5-7 volts. To charge the battery, a voltage of 13.5-15 volts is required. The way out is to use a simple switching voltage converter, assembled, for example, based on the LM2577ADJ voltage regulator. By applying 5 volts DC to the input of the converter, 12-15 volts are obtained at the output, which is quite enough to charge a car battery.

Ready voltage converter on LM2577

This micro-wind generator can certainly be improved. Increase the power of the turbine, change the material and height of the mast, add a DC-to-AC mains voltage converter, etc.

Horizontal-axial wind power plant

Parts set:

A plastic pipe with a diameter of 150 mm, an aluminum sheet 1.5-2.5 mm thick, a wooden block 80x40 1 m long, plumbing: flange - 3, corner - 2, tee - 1.
DC motor (generator) 30-60 V, 300-470 rpm.
Wheel-pulley for an engine with a diameter of 130-150 mm (aluminum, brass, textolite, etc.).
Steel pipes with a diameter of 25 mm and 32 mm and a length of 35 mm and 3000 mm, respectively.
Charging module for batteries.
Batteries.
Voltage converter 12 V - 120 V (220 V).

Production of a horizontal-axial "windmill"

Plastic pipe is necessary for the manufacture of wind turbine blades. A segment of such a pipe, 600 mm long, is cut lengthwise into four identical segments. The windmill requires three blades, which are made from the obtained segments by cutting off a piece of material diagonally for the entire length, but not exactly from corner to corner, but from the lower corner to the upper corner, with a slight indent from the latter. The processing of the lower part of the segments is reduced to the formation of a fastening petal on each of the three segments. To do this, a square about 50x50 mm in size is cut along one edge, and the remaining part serves as a mounting petal.

The blades of the wind turbine are fixed on the wheel-pulley with the help of bolted connections. The pulley is mounted directly on the shaft of the DC motor - generator. A simple wooden block with a section of 80x40 mm and a length of 1 m is used as the chassis of the wind turbine. The generator is installed at one end of the wooden block. At the other end of the bar, a "tail" is mounted, made of aluminum sheet. At the bottom of the bar, a 25 mm metal pipe is attached, designed to act as the shaft of the rotary mechanism. A three-meter metal pipe 32 mm is used as a mast. The upper part of the mast is a swivel sleeve where the wind turbine pipe is inserted. The mast support is made from a sheet of thick plywood. On this support, in the form of a disk with a diameter of 600 mm, a construction of sanitary parts is assembled, thanks to which the mast can be easily raised or lowered, or mounted or dismantled. Stretch marks are used to fasten the mast.

All electronics of the wind turbine is mounted as a separate module, the interface of which provides for the connection of batteries and consumer loads. The module includes a battery charge controller and a voltage converter. Such devices can be assembled independently with the appropriate experience, or purchased on the market. There are many different solutions on the market that allow you to get the desired output values \u200b\u200bof voltages and currents.

Combined wind turbines

Combined wind turbines are a serious option for a home energy module. Actually, the combination involves combining in a single system a wind generator, a solar battery, a diesel or gasoline power plant. You can combine in every possible way, based on the possibilities and needs. Naturally, when there is a three-in-one option, this is the most effective and reliable solution.

Also, under the combination of wind turbines, it is supposed to create wind power plants that have two different modifications at once. For example, when the Savonius rotor and the traditional three-bladed machine work in the same bundle. The first turbine operates at low wind flow speeds, and the second only at nominal ones. Thus, the efficiency of the installation is maintained, unjustified energy losses are excluded, and in the case of asynchronous generators, reactive currents are compensated.

Combined systems are technically complex and costly options for home practice.