How to make an induction heater with your own hands according to the scheme. Induction heating, basic principles and technologies Induction heating module of a high-frequency machine

Induction heaters work on the principle of “generating current from magnetism”. An alternating magnetic field is generated in a special coil high power, which generates eddy electric currents in a closed conductor.

A closed conductor in induction cookers is metal dishes, which is heated by eddy electric currents. In general, the principle of operation of such devices is not complicated, and if you have a little knowledge in physics and electrics, assembling an induction heater with your own hands will not be difficult.

The following devices can be made independently:

1. Devices for heating in a heating boiler.
2. Mini ovens for melting metals.
3. Slabs for cooking food.

An induction cooker with your own hands must be made in compliance with all the rules and regulations for the operation of these devices. If an electromagnetic radiation hazardous to humans is emitted outside the body in lateral directions, then it is strictly prohibited to use such a device.

In addition, a great difficulty in designing a stove is the selection of material for the base of the hob, which must meet the following requirements:

1. Ideally conduct electromagnetic radiation.
2. Not conductive.
3. Withstand high temperature load.

In household induction hobs, expensive ceramics are used, when made at home induction hob, find worthy alternative such material is rather difficult. Therefore, to begin with, you should design something simpler, for example, an induction furnace for hardening metals.

Manufacturing instruction

Blueprints

To make a furnace you will need the following materials and tools:

• solder;
• textolite board.
• mini drill.
• radioelements.
• thermal paste.
• chemical reagents for etching the board.

Additional materials and their features:

1. For making a coil, which will emit the alternating magnetic field necessary for heating, it is necessary to prepare a piece of copper tube with a diameter of 8 mm and a length of 800 mm.
2. Powerful power transistors are the most expensive part of a homemade induction machine. To install the frequency generator circuit, you need to prepare 2 such elements. For these purposes, transistors of the following brands are suitable: IRFP-150; IRFP-260; IRFP-460. In the manufacture of the circuit, 2 identical of the listed field-effect transistors are used.
3. For the manufacture of an oscillatory circuit you will need ceramic capacitors with a capacity of 0.1 mF and an operating voltage of 1600 V. In order for the coil to form alternating current high power, 7 such capacitors are required.
4. When operating such an induction device, field-effect transistors will get very hot and if radiators made of aluminum alloy are not connected to them, then after a few seconds of operation at maximum power, these elements will fail. The transistors should be placed on the heat sinks through a thin layer of thermal paste, otherwise the efficiency of such cooling will be minimal.
5. Diodes that are used in an induction heater must be ultra-fast. Most suitable for this circuit, diodes: MUR-460; UF-4007; HER - 307.
6. Resistors used in circuit 3: 10 kOhm with a power of 0.25 W - 2 pcs. and 440 ohms with a power of 2 watts. Zener Diodes: 2 pcs. with an operating voltage of 15 V. The power of the zener diodes must be at least 2 W. The choke for connection to the power terminals of the coil is used with induction.
7. To power the entire device, you will need a power supply unit with a capacity of up to 500 watts. and voltage 12 - 40 V. You can power this device from a car battery, but you will not be able to get the highest power readings at this voltage.

The process of manufacturing an electronic generator and a coil itself takes a little time and is carried out in the following sequence:

1. From copper pipe a spiral with a diameter of 4 cm is made.To make a spiral, screw a copper tube onto a rod with flat surface with a diameter of 4 cm. The spiral should have 7 turns, which should not touch. Mounting rings are soldered to the 2 ends of the tube for connecting to the radiators of the transistor.
2. The printed circuit board is manufactured according to the scheme. If it is possible to supply polypropylene capacitors, then due to the fact that such elements have minimal losses and stable operation at large amplitudes of voltage fluctuations, the device will work much more stable. The capacitors in the circuit are installed in parallel, forming an oscillatory circuit with the copper coil.
3. Metal heating occurs inside the coil after the circuit is connected to a power supply or battery. When heating the metal, it is necessary to ensure that there is no short circuit of the spring windings. If the heated metal touches 2 turns of the coil at the same time, then the transistors fail instantly.

Nuances

1. When conducting experiments on heating and quenching metals, inside the induction coil, the temperature can be significant and is 100 degrees Celsius. This heating effect can be used to heat domestic water or to heat a home.
2. Heater circuit discussed above (Figure 3), at maximum load is capable of providing radiation of magnetic energy inside the coil equal to 500 W. This power is not enough to heat a large volume of water, and the construction of a high-power induction coil will require the manufacture of a circuit in which it will be necessary to use very expensive radioelements.
3. A budget solution for the organization of induction heating of liquid, is the use of several devices described above, arranged in series. At the same time, the spirals should be on the same line and not have a common metal conductor.
4. Asused pipe made of of stainless steel with a diameter of 20 mm. Several induction coils are "strung" onto the pipe, so that the heat exchanger is in the middle of the coil and does not come into contact with its coils. With the simultaneous switching on of 4 such devices, the heating power will be about 2 kW, which is already enough for instantaneous heating of the liquid with a small circulation of water, up to values ​​that allow the use this design in the supply of warm water to a small house.
5. If you combine such a heating element with well insulated tank, which will be located above the heater, then the result will be a boiler system in which the liquid will be heated inside stainless pipe, heated water will rise up, and a colder liquid will take its place.
6. If the area of ​​the house is significant, then the number of induction coils can be increased to 10 pieces.
7. The power of such a boiler can be easily adjusted. by turning off or turning on the spirals. The more sections that are simultaneously switched on, the more the power of the heating device operating in this way will be.
8. To power such a module, you will need a powerful power supply. If an inverter welding machine is available direct current, then it is possible to make a voltage converter of the required power from it.
9. Due to the fact that the system operates on a constant electric current , which does not exceed 40 V, the operation of such a device is relatively safe, the main thing is to provide a fuse block in the generator power circuit, which, in the event of a short circuit, will de-energize the system, thereby excluding the possibility of a fire.
10. Thus, you can organize "free" heating of the house., provided that it is installed to power induction devices rechargeable batteries, which will be charged by the energy of the sun and wind.
11. Batteries should be combined in sections of 2, connected in series. As a result, the supply voltage with such a connection will be at least 24 V., which will ensure the operation of the boiler at high power. In addition, a series connection will reduce the current in the circuit and increase the battery life.

1. Operation of homemade induction heating devices, does not always allow to exclude the spread of harmful to humans electromagnetic radiation, therefore the induction boiler should be installed in non-residential premises and shielded with galvanized steel.
2. Mandatory when working with electricity the safety regulations must be followed and, especially this applies to AC networks with a voltage of 220 V.
3. As an experiment can be made hob for cooking food according to the scheme indicated in the article, but it is not recommended to operate this device constantly due to imperfections self-made shielding this device, because of this, it is possible for the human body to be exposed to harmful electromagnetic radiation, which can adversely affect health.

Appliances that heat using electricity, not gas, are safe and convenient. These heaters do not produce soot and bad smell but consume a large number of electricity. An excellent solution is to assemble an induction heater with your own hands. This is both cost savings and a contribution to the family's budget. There are many simple circuits by which an inductor can be assembled by yourself.

In order to make it easier to understand the diagrams and correctly assemble the structure, it will be useful to look into the history of electricity. Heating methods metal structures electromagnetic current coils are widely used in industrial production household appliances- boilers, heaters and stoves. It turns out that you can make a working and durable induction heater with your own hands.

How the devices work

How the devices work

The famous British scientist of the 19th century, Faraday, spent 9 years researching to convert magnetic waves into electricity. In 1931, a discovery was finally made, called electromagnetic induction. The wire winding of the coil, in the center of which is a magnetic metal core, creates a magnetic field under an alternating current. The vortex flows heat the core.

An important nuance - heating will occur if the alternating current supplying the coil changes the vector and sign of the field at high frequencies.

Faraday's discovery began to be used both in industry and in the manufacture of home-made motors and electric heaters. The first smelter based on a vortex inductor was opened in 1928 in Sheffield. Later, according to the same principle, the workshops of factories were heated, and for heating water, metal surfaces connoisseurs assembled the inductor with their own hands.

The diagram of the device of that time is still valid today. Classic example- induction boiler, which includes:

• metal core;
• frame;
• thermal insulation.

Lighter weight, size and higher efficiency are achieved by using thin steel pipes serving as the core of the core. V kitchen tiles the inductor is a flattened coil located near the hob.

The features of the circuit for accelerating the current frequency are as follows:

• industrial frequency of 50 Hz is not suitable for homemade devices;
• direct connection of the inductor to the network will lead to hum and weak heating;
• effective heating is carried out at a frequency of 10 kHz.

Assembly according to diagrams

Any person familiar with the laws of physics can assemble an inductive heater with their own hands. The complexity of the device will vary depending on the degree of preparation and experience of the master.

There are many video tutorials that you can follow to create an effective device. It is almost always necessary to use the following basic components:

• steel wire with a diameter of 6-7 mm;
• copper wire for the inductor;
• metal mesh (to hold the wire inside the case);
• adapters;
• pipes for the body (plastic or steel);
• high frequency inverter.

This will be enough to assemble an induction coil with your own hands, and in fact it is she who is at the heart instantaneous water heater... After preparing the required elements you can go directly to the manufacturing process of the device:

• cut the wire into 6-7 cm pieces;
• cover the inside of the pipe with a metal mesh and fill the wire to the top;
• similarly close the pipe opening from the outside;
• wind copper wire on the plastic case at least 90 times for the coil;
• insert the structure into the heating system;
• use an inverter to connect the coil to electricity.

It is advisable to pre-ground the inverter and prepare antifreeze or water.

Using a similar algorithm, you can easily assemble an induction boiler, for which you should:

• cut blanks from steel pipe 25 by 45 mm with a wall not thicker than 2 mm;
• weld them together, connecting them with smaller diameters to each other;
• weld iron covers to the ends and drill holes for threaded branch pipes;
• make a mount for an induction stove by welding two corners on one side;
• insert hob into the mount from the corners and connect to the mains;
• add coolant to the system and turn on the heating.

Many inductors operate at power no higher than 2 - 2.5 kW. These heaters are designed for a room of 20 - 25 m². If the generator is used in a car service, you can connect it to a welding machine, but it is important to take into account certain nuances:

• AC is required, not DC like an inverter. Welding machine will have to investigate for points where the voltage has no direct direction.
• The number of turns to a wire of a larger cross-section is selected by mathematical calculation.
• Cooling of working elements will be required.

Creation of sophisticated devices

It is more difficult to make a HDTV heating installation with your own hands, but this is subject to radio amateurs, because to collect it, you will need a multivibrator circuit. The principle of operation is similar - eddy currents arising from the interaction of the metal filler in the center of the coil and its own high magnetic field, heat the surface.

Construction of HDTV installations

Since even small size the coils generate a current of about 100 A, together with them it will be necessary to connect a resonating capacitor to balance the induction draft. There are 2 types of working circuits for heating HDTV at 12V:

• connected to the mains supply.

• targeted electric;
• connected to the mains supply.

In the first case, a mini HDTV installation can be assembled in an hour. Even in the absence of a 220 V network, such a generator can be used anywhere, but in the presence of car batteries as power sources. Of course, it is not powerful enough to melt metal, but it is capable of heating up to the high temperatures required for small work, for example, heating knives and screwdrivers to of blue color. To create it, you need to purchase:

• field-effect transistors BUZ11, IRFP460, IRFP240;
• car battery from 70 A / h;
• high voltage capacitors.

The 11 A power supply current drops to 6 A during the heating process due to metal resistance, but the need for thick wires that can withstand a current of 11-12 A is still needed to avoid overheating.

The second circuit for an induction heating installation in a plastic case is more complex, based on the IR2153 driver, but it is more convenient to build a resonance with a 100k regulator using it. It is necessary to control the circuit through a network adapter with a voltage of 12 V. The power section can be connected directly to the main 220 V network using a diode bridge. The resonance frequency is 30 kHz. The following items are required:

• ferrite core 10 mm and choke 20 turns;
• copper tube as an HDTV coil with 25 turns per mandrel 5-8 cm;
• capacitors 250 V.

Vortex heaters

A more powerful installation capable of heating bolts up to yellow color, can be assembled in a simple manner. But during operation, the heat generation will be quite large, so it is recommended to install radiators on transistors. You will also need a choke, which can be borrowed from the power supply of any computer, and the following auxiliary materials:

• steel ferromagnetic wire;
• copper wire 1.5 mm;
• field-effect transistors and diodes for reverse voltage from 500 V;
• Zener diodes with a power of 2-3 W, calculated for 15 V;
• simple resistors.

Depending on the desired result, winding the wire on a copper base is 10 to 30 turns. Next comes the assembly of the circuit and preparation of the base coil of the heater from about 7 turns of 1.5 mm copper wire. It connects to the circuit and then to the electricity.

Craftsmen familiar with welding and operating a three-phase transformer can further increase the efficiency of the device while reducing weight and size. To do this, you need to weld the bases of two pipes, which will serve as both a core and a heater, and after winding, weld two nozzles into the body to carry out the supply and removal of the coolant.

Focusing on the schemes, you can quickly assemble inductors of various capacities for heating water, metals, heating a house, garage and car service. It is also necessary to remember about the safety rules for the effective service of heaters of this type, because the leakage of the coolant from homemade device can end in fire.

There is certain conditions organization of work:

• the distance between the induction boiler, walls, electrical appliances should be at least 40 cm, and it is better to retreat 1 m from the floor and ceiling;
• with the help of a pressure gauge and an air venting device, a safety system is provided behind the outlet pipe;
• use devices, preferably in closed circuits with forced circulation coolant;
• can be used in plastic pipelines.

Self-assembly of induction generators is inexpensive, but not free, because you need enough components good quality... If a person does not have special knowledge and experience in radio engineering and welding, then you should not independently assemble a heater for a large area, because the heating power will not exceed 2.5 kW.

but self-assembly inductor can be considered as self-education and professional development of the owner of the house in practice. You can start with small appliances simple schemes, and since the principle of operation in more complex devices is the same, only additional elements and frequency converters, then it will be easy to master it in stages and quite budget.

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