Electrical generators are an additional energy source for home. In case of great remoteness of the main power grid, it may well replace them. Frequent power interruptions are forced to install alternate current generators.
They are not cheap, whether there is no sense to spend more than 10,000 tr. For the device if you can make the generator from the electric motor itself? Of course, for this you will use some electrical skills, and tools. The main thing is not to spend money.
You can collect a simple generator with your own hands, it will be relevant if you need to cover the temporary shortage of electricity. For more serious cases, it is not suitable, since it does not have sufficient functionality and reliability.
Naturally, in the process of manual assembly there are quite a few difficulties. Required parts and tools may be absent. Understanding experience and skills in such work can restart fear. But a strong desire will be the main stimulus, and will help overcome all time-consuming procedures.
Thanks to the electromagnetic induction, an electric current is formed in the generator. This is because the winding moves in an artificially created magnetic field. This is the principle of operation of the electric generator.
The movement of the generator gives the engine internal combustion low power. It can work on gasoline, gas or diesel fuel.
In the electrical generator device there is a rotor and a stator. The magnetic field is created using the rotor. Magnets are attached on it. The stator is a fixed part of the generator, and consists of special steel plates and coils. There is a small gap between the rotor and the stator.
There are two types of electric generator. The first has synchronous rotation of the rotor. He has a complex design, and low efficiency. In the second type, the rotor rotates asynchronously. According to the principle of action - it is simple.
Asynchronous engines lose the minimum of energy, whereas in synchronous generators, the loss rate reaches 11%. Therefore, electric motors with asynchronous rotation of the rotor are very popular in household appliances, and at various factories.
During operation, voltage drops may occur, they destructively affect household appliances. For this, there is a rectifier at the weekend.
Asynchronous generator is simple in maintenance. His body is reliable and sealed. You can not be afraid for household appliances that have an ohmic load, and sensitive to voltage drops. High efficiency, and a long period of operation, make the device in demand, and it can be assembled independently.
What do you need to build a generator? First, you need to pick up a suitable electric motor. It can be taken from the washing machine. Independently do the stator is not worth it, it is better to use ready decisionwhere there are windings.
It is worth immediately stocking sufficient copper wires, and insulating materials. Since any generator will produce voltage jumps, you will need a rectifier.
According to the instructions for the generator, it is necessary to make power calculation. In order for the future device to outreach the required power, it needs to give a speed of slightly more rated power.
We use the tachometer and turn on the engine to the network, so you can find out the rotational speed of the rotor. You need to add 10% to the value, this will allow you to not bring the engine before overheating.
Capacitors will help maintain the required voltage level. They are selected depending on the generator. For example, for power in 2 kW, the capacity of capacitors in 60 μF will be required. Such details need 3pcs with the same capacity. To ensure that the device is safe, it needs to be grounded.
Everything is simple here! Condensers according to the "Triangle" scheme are connected to the electric motor. In the process of work, periodically need to check the temperature of the housing. Its heating can occur due to incorrectly selected capacitor capacitors.
Behind the homemade generator not possessing automation, you need to constantly monitor. Arriving over time, heating will lower the efficiency. Then the device must be given time for cooling. From time to time, voltage, speed, and current strength should be measured.
Incorrectly calculated characteristics are not able to give the equipment required power. Therefore, before the start of the assembly, drawing works should be carried out, and stock schemes.
It is possible that homemade device will accompany frequent breakdowns. It is not worth it to be surprised, since the hermetic installation of all elements of the electric generator at home will almost can not.
So, how to make a generator from the electric motor now I hope it is clear. If there is a desire to construct the device, the power of which should be enough for simultaneous work household appliances and lighting lamps, or a construction tool, then need to be folded their power and choose the desired engine. It is desirable that it was with a small power margin.
If the manual assembly of the electric generator has suffered a failure, should not be desirable. There are many on the market modern modelsnot needed permanent supervision. They can be of different power, and fairly economical. On the Internet there are photos of generators, they will help to evaluate the dimensions of the device. The only minus is their high costs.
For nutrition household devices And industrial equipment requires a source of electricity. Earn electric current is possible in several ways. But the most promising and cost-effective, today, is the generation of current by electric machines. The simplest in the manufacture, cheap and reliable in operation was an asynchronous generator that produces the lion's share of electricity consumed.
The use of electrical machines of this type is dictated by their advantages. Asynchronous electric generators, in contrast, provide:
These and other properties of asynchronous generators are laid in their design.
The main working parts of the asynchronous generator is the rotor (movable part) and the stator (motionless). Figure 1, the rotor is located on the right, and the stator on the left. Pay attention to the rotor device. It does not see the windings from the copper wire. In fact, the windings exist, but they consist of aluminum rods of short-circuited rings located on both sides. On the photo, the rods are visible in the form of oblique lines.
The design of the short-circuited windings is formed, the so-called "waste cell". The space inside of this cell is filled with steel plates. To be accurate, the aluminum rods are included in the grooves done in the Rotor Core.
Fig. 1. Rotor and an asynchronous generator stator
Asynchronous machine, the device of which is described above, is called a generator with a short-circuited rotor. The one who is familiar with the design of an asynchronous electric motor probably noticed the similarity in the structure of these two machines. In essence, they do not differ in any way, since an asynchronous generator and a short-circuit electric motor is almost identical, with the exception of additional excitation capacitors used in the generator mode.
The rotor is located on the shaft, which sits on the bearings clamping on both sides with covers. The whole design is protected by a metal housing. The average and high power generators require cooling, so the fan is additionally installed on the shaft, and the housing itself makes the ribbed (see Fig. 2).
Fig. 2. Asynchronous generator assembly By definition, the generator is a device that converts mechanical energy into an electric current. It does not matter what energy is used to rotate the rotor: the wind, potential energy of water, or internal energy transformed by the turbine or the engine to mechanical.
As a result of rotation of the rotor, magnetic power lines formed by the residual magnetization of steel plates are crossed by the stator winding. EMF is formed in the coils, which, when connecting active loads, leads to the formation of the current in their circuits.
It is important that the synchronous speed of rotation of the shaft slightly (about 2 to 10%) exceeded the synchronous frequency of the AC (set by the number of poles of the stator). In other words, it is necessary to ensure asynchrony (mismatch) of the rotational speed on the magnitude of the sliding of the rotor.
It should be noted that the current thus obtained will be small. To increase the output power, it is necessary to increase the magnetic induction. Protecting the efficiency of the device by connecting capacitors to the conclusions of the stator coils.
Figure 3 shows the scheme of a welding asynchronous alternator with condenser excitation (left part of the circuit). Note that the excitation condensers are connected according to the triangle scheme. The right side of the pattern is the actual scheme of the inverter welding machine itself.
Fig. 3. Scheme of a welding asynchronous generator There are other, more complex excitation schemes, for example, using inductance coils and capacitor batteries. An example of such a schema is shown in Figure 4.
Figure 4. Diagram of the device with inductors The main difference between the synchronous alternator from the asynchronous generator in the rotor design. In the simultaneous machine, the rotor consists of wire windings. To create magnetic induction, an autonomous power supply is used (often an additional low-power DC generator located on a single axis with a rotor).
The advantage of the synchronous generator is that it generates a better current and easily synchronized with other alternators of this type. However, synchronous alternators are more sensitive to overloads and KZ. They are more expensive from their asynchronous fellow and demanding more in service - it is necessary to monitor the condition of the brushes.
The harmonic coefficient or an asynchronous generator clearing is lower than that of synchronous alternator. That is, they produce practically clean electricity. There are more stable on such currents:
Asynchronous generators provide confident launch of electric motors requiring large starting currents. According to this indicator, they are actually not inferior to synchronous machines. They have less jet loads, which has a positive effect on thermal mode, as less energy is spent on reactive power. Asynchronous alternator has the best stability of the output frequency at different speeds of rotation of the rotor.
The short-circuited type generators received the most distribution, due to the simplicity of their design. However, there are other types of asynchronous machines: alternators with a phase rotor and device, using permanent magnetsforming an excitation chain.
Figure 5, for comparison, two types of generators are shown: left on the basis, and on the right - an asynchronous machine based on blood pressure with a phase rotor. Even with a fluid look at schematic images, a complicated phase rotor design is visible. Attracts the presence of contact rings (4) and the mechanism of briefs holders (5). Figure 3 indicates the grooves for the wire winding, which needs to be given a current to excite it.
Fig. 5. Types of asynchronous generators The presence of excitation windings in the asynchronous generator rotor increases the quality of the generated electric current, however, such advantages are lost as simplicity and reliability. Therefore, such devices are used as a source of autonomous power only in those areas where it is difficult to do without them. Permanent magnets in the rotors are used mainly for the production of low-power generators.
The most commonly applying generator sets with a short-circuited rotor is most common. They are inexpensive, practically do not need maintenance. Devices equipped with trigger capacitors, have decent indicators of the efficiency.
Asynchronous alternators are often used as autonomous or reserve source Nutrition. They work with them, they are used for powerful mobile and.
Three-phase winding alternates confidently start a three-phase electric motor, so often used in industrial power plants. They can also feed equipment in single-phase networks. The two-phase mode allows you to save fuel in the DVS, since unused windings are in idle mode.
The scope of application is quite extensive:
Asynchronous alternators are convenient for the construction of local wind and hydraulic power plants.
Let's notify immediately: it will not be about making a generator from scratch, but about the alternating an asynchronous engine in an alternator. Some craftsmen use the finished stator from the motor and experiment with the rotor. The idea is to make the Rotor Pole with the help of neodymium magnets. Approximately it may look like a blank with glitched magnets (see Fig. 6):
Fig. 6. Blank with glued magnets You stick the magnets on a specially sharpened blank planted on the motor shaft, observing their polarity and the shear angle. This will require at least 128 magnets.
The finished design must be adjusted to the Stator and at the same time provide a minimum gap between the teeth and the magnetic poles of the manufactured rotor. Since the magnets are flat, they will have to grind them or turn it out, while the construction is constantly cooling, since neodymium loses its magnetic properties when high temperatures. If you do everything right - the generator will earn.
The problem is that in handicraft conditions it is very difficult to make an ideal rotor. But if you have a lathe and you are ready to spend a few weeks for fitting and refinement - you can experiment.
I suggest a more practical option - turning an asynchronous engine to the generator (see the video below). To do this, you need an electric motor with a suitable power and an acceptable frequency of rotation of the rotor. The engine power must be at least 50% higher from the required power of the alternator. If such an electric motor is at your disposal - proceed to processing. Otherwise, it is better to buy a ready generator.
For processing, you will need 3 CBG-MN brand condenser, MBGO, MBGT (you can take other brands, but not electrolytic). Capacitors pick up at least 600 V voltage (for a three-phase engine). The reactive power of the generator q associated with the capacitance of the condenser is the following dependence: Q \u003d 0.314 · U 2 · C · 10 -6.
With an increase in the load, reactive power increases, and therefore, to maintain a stable voltage U, it is necessary to increase the capacitors, adding new containers by switching.
Video: Making an asynchronous generator from a single-phase engine - Part 1
Part 2
In practice, usually choose the average value, assuming that the load will not be maximum.
Featuring the parameters of the capacitors, connect them to the conclusions of the stator windings as shown in the diagram (Fig. 7). The generator is ready.
Fig. 7. Constressor connection scheme Asynchronous generator does not require special care. Its service is to control the status of bearings. At nominal modes, the device can work for years without operator intervention.
Weak link - capacitors. They may fail, especially when their rates are incorrectly chosen.
When working, the generator is heated. If you often connect Hypersed loads - follow the device temperature or take care of additional cooling.
The idea has an autonomous source of electrical energy and not depend on the stationary state network concerns the minds of many residents of the countryside.
It is quite simple to implement it: you need a three-phase asynchronous electric motor that can be used even from the old, written off industrial equipment.
The generator from the asynchronous engine is done according to one of the three schemes published in this article. It will be free and securely convert mechanical energy into electricity.
To eliminate errors at the project stage, it is necessary to pay attention to the design of the acquired engine, as well as its electrical characteristics: power consumption, power voltage, number of rotor revolutions.
Asynchronous machines are reversible. They are able to work in mode:
· The electric motor when the external voltage is applied to them;
· Or generator if their rotor rotates a source of mechanical energy, for example, a water or wind wheel, an internal combustion engine.
Pay attention to the factory plate, the design of the rotor and the stator. Consider their features when creating a generator.
He has three isolated windings for nutrition from each voltage phase on the general core of the magnetic pipeline.
They are connected in one of two ways:
1. Star when all the ends are collected in one point. On the 3 beginnings and the total output of the ends is supplied voltage in four wires.
2. Triangle - the end of one windows is connected to the beginning of another so that the scheme is collected by the ring and only three wires come out of it.
This information is described in more detail in the article of my site aboutconnecting a three-phase motor into a domestic single-phase network.
It also creates a magnetic circuit and three windings. They are connected in one of two ways:
1. Through contact conclusions from the engine with a phase rotor;
2. Spit close to the aluminum insert into the design of the Belich Wheel - asynchronous machines.
We need a short-circuit rotor. All schemes are designed for it.
The design of the phase rotor can also be used as a generator. But it will have to remake it: simply shunt all the outputs between themselves.
The operation of the generator will affect:
1. The diameter of the winding wire. It directly depends on the heating of the design and the value of the applied power.
2. The estimated rotor speed indicated by the number of revolutions.
3. Method for connecting windings in a star or triangle.
4. The magnitude of the energy loss, determined by the efficiency and cosine φ.
We look at the plate or calculate the indirect methods.
You must perform two actions:
1. Protect the rotor from the source of the outsider mechanical power.
2. Encour the electromagnetic field in the windings.
If everything is clear with the first item, it is enough to connect the capacitors to the windings to the windings by creating a capacitive load of a certain amount.
For this question, several scheme options have been developed.
Capacitors include the windings between each pair.
In this scheme, start-up and working capacitors are connected to their switches.
Capacitors are included in parallel to each winding. On the output terminals, a linear voltage of 220 volts is created.
The easiest way to use paper capacitors with voltage from 500 volts and above. Electrolytic models are better not to apply: they can boil and explode.
The formula for determining the container has the form:C \u003d Q / 2π ∙ F ∙ U2.
In it q - reactive power, F - frequency, u - voltage.
Not always local electrical stars are able to fully provide electricity at home, especially if it concerns country Dacha and mansions. Interruptions with constant power supply or its complete absence causes to look for electricity. One of these is the use - instrument capable of converting and accumulate electricityUsing the most unusual resources (energy, tides and sings). His principle of operation is quite simple, which makes it possible to make the electric generator with your own hands. Perhaps the self-made model will not be able to compete with the analogue of the factory assembly, but this is a great way to save more than 10,000 rubles. If we consider the homemade electrical generator as a temporary alternative source of power supply, then it is quite possible to do the homemade.
How to make an electric generator that it will be necessary for this, as well as what nuances will have to be considered, learn later.
The desire to have an electric generator in its use is overshadowed by one nuisance - this is in the cost of the aggregate. No matter how cool, but the most low-power models have a fairly transcendent cost - from 15,000 rubles and higher. It is this fact that comes to the idea of \u200b\u200bhis own creation of the generator. However, Sam the process can be difficult, if a:
If all this and a huge desire are present, then you can try to collect generator, guided by the assembly instructions and the attached scheme.
It is no secret that the purchase of the electric generator will have a more advanced list of features and functions, while homemade is able to bring and malfunctions to the most inappropriate moments. Therefore, buy or do it yourself - the question is purely individual, requiring a responsible approach.
The principle of operation of the electric generator is based on the physical phenomenon of electromagnetic induction. The conductor passing through an artificially created electromagnetic field creates a pulse that is converted to d.C..
The generator has an engine that is able to produce electricity, burning in its compartments a certain type of fuel:, or. In turn, fuel, falling into the combustion chamber, in the combustion process produces gas, which rotates the crankshaft. The latter transfers the impetus to the slave shaft, which is already able to provide a certain amount of energy at the output.
These works among themselves do not have almost nothing in common, as it is necessary to make different systems of the system in essence and destination. For the manufacture of the other element, approved mechanisms and devices that can be used or remade to the required node are used. One of the options for creating a generator, often used in the manufacture of the wind generator - the manufacture of an asynchronous electric motor, which is most successful and efficiently solving the problem. Consider a question in Read more:
Asynchronous engine is the best "blank" for the manufacture of the generator. He has for this best indicators By sustainability to short circuit, less demanding of dust or dirt. Moreover, asynchronous generators We produce more "clean" energy, the clearing (the presence of higher harmonics) in these devices is only 2% against 15% of synchronous generators. Higher harmonics contribute to the heating of the engine and knock the rotation mode, so their small amount is a large plus design.
Asynchronous devices do not have rotating windings, which largely removes the possibility of their failure or damage from friction or closure.
Also important factor is the presence of 220V voltage windings or 380 V, which allows you to connect consumption devices directly to the generator, bypassing the current stabilization system. That is, while there is a wind, the devices will work in the same way as from the network.
The only difference from the work of the full complex in the termination of the work immediately after the odd scenery, while the batteries included in the kit, for some time they feed the consuming devices using its container.
The only change that is entered into the design of the asynchronous engine when it is reworked into the generator, is the installation on the rotor of permanent magnets. To obtain a larger current of the current sometimes rewind windings with a thicker wire having less resistance and giving the best results, but this procedure is not critical, you can do without it - the generator will work.
Rotor asynchronous engine There is no windings or other elements, being, in fact, the usual flywheel. Rotor processing is made in turning machine In terms of metal, it is impossible to do without it. Therefore, when creating a project, it is necessary to immediately resolve the issue of technical support, find a familiar turner or organization engaged in such works. The rotor must be reduced in diameter on the thickness of the magnets that will be installed on it.
There are two ways to install magnets:
Installation of magnets is made by the rutor design lines, i.e. Not equal axis, but somewhat shifted in the direction of rotation (these lines are clearly visible on the rotor). Magnets are placed on alternating poles and fixed on the rotor with glue (epoxy resin is recommended). After drying it, it is possible to assemble the generator, in which our engine has turned around, and move to test procedures.
This procedure allows us to find out the degree of the operation of the generator, experimentally determine the rotation speed necessary to obtain the desired voltage. Usually resort to the help of another engine, for example, the electric drill with the adjustable rotation frequency of the cartridge. Rotating a generator rotor with a voltmeter connected to it or a light bulb is checked which speeds are required for a minimum and what the maximum generator power limit to obtain data on which the windmill will be created.
You can connect any device to test for test purposes (for example, a heater or lighting device) and ensure that it is working. This will help remove all the questions that arise and make any changes if such a need arises. For example, sometimes there are situations with a "sticking" of the rotor that is not starting at weak winds. This occurs during the uneven distribution of magnets and is eliminated by disassembling the generator, disconnecting magnets and reinstalling them in a more uniform configuration.
Upon completion of all the work, a fully working generator appears at the disposal, which from now on needs to be the source of rotation.
To create a windmill, you will need to choose any of the design options that there is a lot. So, there are horizontal or vertical designs of the rotor (in this case, the term "rotor" denotes a rotating part of the wind generator - shaft with blades, driven by the strength of the wind). Have higher efficiency and stability in the production of energy, but need a system of pointing to a stream, which, in turn, needs ease of rotation on the shaft.
The more powerful the generator, the harder it is to rotate and the greater effort should be developed by the windmill, which requires its large sizes. At the same time, the larger the windmill, the more heavier and has a greater inertia of rest, which forms a vicious circle. Usually use the average values \u200b\u200band values \u200b\u200bthat make it possible to form a compromise between the size and ease of rotation.
It is easier to manufacture and are not demanding towards the direction of the wind. At the same time, they have less efficiency, since the wind with the same force affects both sides of the blade, it makes it difficult to rotate. In order to avoid this disadvantage, a variety different designs Rotor, such as:
Known orthogonal structures (separated relative to the axis of rotation) or helicoid (blades that have a complex shape resembling spiral coils). All these designs have their advantages and disadvantages, the main of which is the lack of mathematical model Rotation of this or that type of blades making calculations is extremely complex and approximate. Therefore, they act by the method of trial and errors - the experimental model is created, its disadvantages are found, with which the working rotor is manufactured.
The most simple and common design is the rotor, but in recent times there are many descriptions of other wind generators created on the basis of other types.
The rotor device is easy - the shaft on the bearings, on the upper part of which the blades are strengthened, which are rotating under the action of wind and transmit torque to the generator. The manufacture of the rotor is carried out of the available materials, the installation does not require an excessive height (usually raised by 3-7 m), it depends on the strength of winds in the region. Vertical designs almost do not require care or maintenance, which facilitates the operation of the wind generator.
