Electrical circuit of a voltage converter 12-220 volts. High voltage and more
There may be times when you need to use a portable electronic device in a place where there is no mains voltage equal to 220 volts. The easiest way to do this is to use a battery, the voltage of which is usually 12 volts. But not all devices can operate on reduced voltage. To solve this problem, converters from 12 to 220 volts are used. Another name for them is inverters.
Purpose and parameters of inverters
An inverter is a device that is designed to convert the amplitude and shape of a signal. It transforms AC network voltage into DC voltage. Signal converters are often connected to automobile electrical networks, generators or stationary battery packs. This is necessary to receive alternating current used in power supply: household appliances, power tools, radio equipment. The options for using the inverter are varied:
- ensuring continuity of power supply to electrical devices and instruments in the event of an accident in the 220 volt network;
- organization of complete autonomy from power grids;
- during long trips on vehicles that use generators or batteries, for example, a boat, an airplane, a car.
Inverters differ from each other primarily in the shape of the output signal and power. She determines maximum load, which can be connected to the device.
Types and types of devices
Inverters differ in their operating principle. The first devices were produced of the mechanical type. Then, they were replaced by semiconductor ones, and modern circuitry is already built on pulse blocks. There are the following principles for constructing circuits:
- Bridge type (transformerless). Used for power devices with a power of more than 500 VA and above.
- Using a transformer with a zero terminal. Designed for power devices with power up to 500 VA.
- Transformer bridge circuit. It is used for power devices in a wide power range up to tens of kilowatts.
In addition, they are divided, depending on the supply voltage requirements, into single-phase and three-phase devices. By type of output signal there are:
- with a rectangular shape;
- with a stepped shape;
- with a sinusoidal shape.
For equipment and devices that do not require a correct sinusoidal signal, such as heaters, lights, converters with rectangular, trapezoidal, triangular output voltage are used. The main advantage of such converters is their low price.
For equipment that requires reliable power supply, inverters with the correct sine waveform are used. Such equipment is significantly more expensive, but its stability is also higher.
Main characteristics of converters
First of all, the power of the inverter is taken into account when choosing. The required power is calculated in total based on the load planned for connection with the addition of 25% to the result obtained. This allows you to avoid overloading the converter and creates the best operating conditions for it. The most popular are inverters with a power of up to 5000 W, but even 15,000 W may not be enough to connect all household energy consumers. For portable devices, inverters with a load capacity of up to 1 kW are used.
In addition to the rated power, there is its peak value - this is the highest power level that the inverter can withstand for a short time without negative consequences for its operation. In descriptions of device parameters, its value is most often indicated.
It is necessary to understand that the power when turning on a number of devices that use motors or powerful starting capacitors in their design differs from the nominal one. These are devices such as pumps, refrigerators, washing machines, vacuum cleaners that consume peak power when turned on. At the same time, equipment such as a TV, computer, lamp, tape recorder does not exceed the rated value of its power. The power of devices is measured in volt-amperes (VA), but you can often find it indicated in watts (W). The relationship between these units of measurement is described by the relation: 1 W = 1.6 VA.
An important parameter is the shape of the output signal. A regular sinusoid is characterized by the frequency of the voltage and the smoothness of its change. This parameter is important for systems with active power. Such devices include: electric motors, pumps, compressors. In most cases for food household appliances Converters with a modified sine wave are suitable. Also to technical specifications inverters from 12 to 220 volts include:
- Acceptable input voltage range. Indicates the amplitude of the input signal at which stability in the operation of the device is ensured.
- The level of the lowest and highest output voltage. Is no more than 10 volts from the nominal value.
- Coefficient value useful action(efficiency). A range of 85 to 90 percent is considered good.
- Protection class. Must be at least IP54 according to international classification.
- Cooling system. Can be used passive or active using fans.
- Additional features. The most popular functions are protection against short circuit, overload, overheating, and increased amplitude of the input signal. Among the accompanying attributes, attention is drawn to the ease of connection to the terminals, the shape and weight of the device.
When choosing, you will need to decide for what type of device the current converter from 12 to 220 volts will be used. For autonomous operation systems, the possibility is being considered parallel connection inverter to batteries and AC mains. For example, for an autonomous heating system.
Popular manufacturers
When choosing, you should pay attention to the manufacturer of the product. As practice shows, different models may have the same characteristics, which makes it difficult right choice. The most popular companies producing inverters are:
Reputable companies monitor compliance with the technical process at all stages of device manufacturing. Such manufacturers have an extensive network of service centers throughout Europe, which makes it easy to carry out warranty and post-warranty service for their products.
Self-production of the device
If for some reason it is not possible to purchase a 12V to 220V voltage converter, then it is easy to make an inverter with your own hands at home. First of all, this applies to analog devices, radio components for which can be taken from old equipment. In addition, with self-assembly, you will be able to understand the nuances of construction, which can be useful for repairing devices of this type.
Simple and reliable inverter
There are a large number of different converter circuits. Their operation is based on the use of a master oscillator that controls the operation of transistor switches. And they, in turn, transmit a pulse signal to a transformer, whose task is to convert the signal to a level of 220 volts. The use of powerful field-effect transistors (mosfets) as switches greatly simplifies the circuit design of devices.
Using a specialized KR1211EU1 microcircuit as a generator, which has two powerful channels for controlling keys, you can assemble a reliable and simple device.
IRL2505 mosfets are connected to the outputs of the microcircuit, direct and inverse. The IRL2505's open channel resistance is only 0.008 ohms. This makes it possible not to use radiators at the required power of up to 100 W.
The generation frequency of the microcircuit is set by the R1-C1 chain and is calculated by the formula: f=70000/(R1*C1). The R2-C2 chain is designed to smoothly start the generator. A 78L08 is used as a linear stabilizer for DA2, with a stabilization voltage of +8 volts. Resistors are used with a power of 0.25 watts. Capacitor C1 is of a film type, and C6 is of any type, but designed for a rated voltage of at least 400 volts. The transformer is used with windings designed for 220 and 12 volts.
Transistor circuit
A generator operating at a frequency of 57 Hz is used as the basis for the manufacture of the structure. The master oscillator controls the operation of power switches, made of powerful field-effect transistors. These transistors can be replaced with IRFZ40, IRF3205, IRF3808, and bipolar ones with KT815/817/819/805.
The power of the inverter depends on the number of complementary field pairs at the output and the characteristics of the transformer. The output voltage is 220–260 volts. When using two pairs of transistors, the power reaches 300 watts. Such a converter does not require adjustment and, with proper assembly and serviceable radio components, works immediately. When operating without load, current consumption is up to 300 mA. For reliable operation, transistors are installed on the heat sink through insulating gaskets. Power tracks, in case of wiring on a printed circuit board, are made with a width of at least 5 mm or with a wire with a cross-section of 0.75 mm2.
The essence of the device’s operation is to convert direct voltage into alternating voltage, after which the signal is supplied to a step-up transformer. The primary winding of a step-up transformer from 12 to 220 volts has fewer turns than the secondary. When current flows in the primary winding, under the influence of alternating magnetic field, an electromotive force (EMF) appears on the secondary winding. When a load is connected to the secondary winding, alternating current begins to flow through it. To calculate the transformer, you can use reference books or online calculators, but it’s easier to take a ready-made one from an unnecessary uninterruptible power supply.
Powerful booster
Such converters are manufactured according to complex schemes and are difficult to repeat even for experienced radio amateurs. For example, a 12 V 220 by 3000 W inverter circuit:
It is almost impossible to carry out such a scheme with your own hands, since it will be necessary not only to correctly calculate the transformers, but also to correctly configure the master oscillator. And such operations are difficult to perform without special equipment.
The generator is made on the TL081 chip. It is powered by a nine-volt stabilizer. The signal in the microcircuit is converted, reduced in frequency and supplied to power switches. The circuit implements output overload protection, and the input is protected fuse from overvoltage.
Thus, it is not difficult to make a power converter up to 500 watts yourself, but if you need to make a more powerful device, then it is more advisable to buy a ready-made one.
The inverter consists of a master oscillator of 50 Hertz (up to 100 Hz), which is built on the basis of the most common multivibrator. Since the publication of the scheme, I have observed that many have successfully repeated the scheme, the reviews are quite good - the project was a success.
This circuit allows you to get almost mains 220 Volts with a frequency of 50 Hz at the output (depending on the frequency of the multivibrator. The output of our inverter is rectangular pulses, but please do not rush to conclusions - such an inverter is suitable for powering almost all household loads, with the exception of those loads that have built-in motor that is sensitive to the shape of the supplied signal.
TV, players, charging device from laptops, laptops, mobile devices, soldering irons, incandescent lamps, LED bulbs, LDS, even a personal computer - all this can be powered without problems from the proposed inverter.
A few words about the power of the inverter. If you use one pair of power switches of the IRFZ44 series with a power of about 150 watts, the output power is indicated below depending on the number of pairs of keys and their type
Transistor Number of pairs Power, W)
IRFZ44/46/48 1/2/3/4/5 250/400/600/800/1000
IRF3205/IRL3705/IRL 2505 1/2/3/4/5 300/500/700/900/1150
IRF1404 1/2/3/4/5 400/650/900/1200/1500Max
But that’s not all, one of those people who assembled this device wrote with pride that he managed to remove up to 2000 watts, of course, and this is real if you use, say, 6 pairs of IRF1404 - really killer keys with a current of 202 Amperes, but of course the maximum the current cannot reach such values, since the terminals would simply melt at such currents.
The inverter has a REMOTE function (remote control). The trick is that to start the inverter you need to apply a low-power plus from the battery to the line to which low-power multivibrator resistors are connected. A few words about the resistors themselves - take everything with a power of 0.25 watts - they will not overheat. The transistors in the multivibrator need to be quite powerful if you are going to pump several pairs of power switches. Of ours, KT815/17 or even better KT819 or imported analogues are suitable.
Capacitors are frequency-setting capacitors, their capacity is 4.7 μF; with this arrangement of multivibrator components, the inverter frequency will be around 60 Hz.
I took the transformer from an old uninterruptible power supply, the power of the trance is selected based on the required (calculated) power of the inverter, the primary windings are 2 to 9 Volts (7-12 Volts), the secondary winding is standard - network.
Film capacitors with a rated voltage of 63/160 volts or more, take the one you have on hand.
Well, that's all, I'll just add that the power switches are high power They will heat up like a stove, they need a very good heat dissipation, plus active cooling. Do not forget to isolate the pairs of one arm from the heat sink to avoid short-circuiting of the transistors.
The inverter does not have any protection or stabilization; perhaps the voltage will deviate from 220 Volts.
Download the PCB from the server
Sincerely - AKA KASYAN
A 12 volt to 220 volt converter with a maximum output power of 500 W is assembled on 2 domestic microcircuits (K155LA3 and K155TM2) and 6 transistors, and several radio components. To increase efficiency and prevent strong heating, very powerful devices are used in the output stage of the device. field effect transistors IRLR2905 with minimal resistance. It is possible to replace it with IRF2804, but the power of the converter will drop slightly
On elements DD1.1 - DD1.3, C1, R1, each standard scheme master oscillator assembled rectangular pulses with an approximate frequency of 200 hertz. From the output of the generator, pulses follow to a frequency divider consisting of elements DD2.1 - DD2.2. As a result, at the output of the divider (pin 6 of element DD2.1), the pulse repetition rate is reduced to 100 hertz, and at output 8 of DD2.2. The signal frequency is 50 hertz.
The rectangular signal from pin 8 of the DD1 chip and from pin 6 of the DD2 chip is supplied to the diodes VD1 and VD2, respectively. In order for the field-effect transistors to open completely, it is necessary to increase the amplitude of the signal that comes from the diode VD1 and VD2; for this, transistors VT1 and VT2 are used. With the help of transistors VT3 and VT4 (they act as a driver), the output power transistors are controlled. If no errors were made during the assembly of the inverter, then it starts working immediately after switching on. It is possible that it may be necessary to select the resistance of resistor R1 so that the output is exactly 50 hertz.
Voltage converter (inverter) 12 / 220 50 Hz 500 W DIY circuit
Silicon transistors VT1, VT3 and VT4 - KT315 with any letter. Transistor VT2 can be replaced with KT361. Stabilizer DA1 - domestic analogue KR142EN5A. All resistors in the circuit have a power of 0.25 W. Any diodes KD105, 1N4002. Capacitor C1 with a stable capacitance - type K10-17. It is possible to use TP1 as a transformer power transformer from an old Soviet TV. All windings must be removed, leaving only the network winding. On top of the network winding, wind two windings simultaneously with PEL wire - 2.2 mm. Field-effect power transistors must be installed on an aluminum finned radiator with a total area of 750 sq.cm.It is recommended that the converter (inverter) be started for the first time through household lamp incandescent 220 volts and a power of 100 - 150 watts, connected in series to one of the supply wires, this will protect against damage to radio components in the event of an error.
When working with boost converters or inverters, follow the electrical safety rules since the work is carried out with a voltage dangerous to the body!!! During the commissioning and assembly process, the output secondary winding must be insulated with rubber tube cambrics to avoid accidental contact.
Radio circuits for beginners for self-assembly
Nowadays, the Internet is replete with all sorts of inverter circuits 12-220 Volt, which are built on TL series microcircuits and field-effect transistors and there is not a single circuit that is as simple as possible, based on domestic element base. I decided to fill this gap.
I suggest for repetition very much simple and reliable inverter circuit(converter) voltage from 12V to 220 volts, for energy saving lamp. The circuit is outrageously simple and at the same time very reliable, it starts up without any problems right away, contains only two transistors and three parts in the harness - it couldn’t be simpler.
Rice. 1. Schematic diagram simple inverter voltage 12V - 220V on two transistors.
As a transformer I used ferrite cups with the following dimensions: diameter - 35 mm, height - 20 mm. The winding of this transformer has no special features. I attach a photo of the ferrite, coil and assembled transformer for the voltage inverter below.
Rice. 2. Ferrite cups for making a transformer for a voltage inverter.
First, the primary winding is wound; it contains 14 turns of wire with a diameter of 0.5 mm; after winding, it must be wrapped in one layer of electrical tape. The secondary winding of the transformer is wound with a wire with a diameter of 0.2 mm and contains 220 turns; we also wrap it with electrical tape in one layer on top. That's it, the transformer is ready, all that remains is to assemble the halves and place them on the bolt.
Rice. 3. Transformer frame with wound inductors.
Rice. 4. Ready-made transformer for a simple 12V - 220V voltage inverter circuit.
Using trial and error, I selected transistors for the circuit, focusing on the minimum current consumption of the circuit. The result was a pair of KT814 and KT940, then the resistance and capacitance were selected. As a result of my experiments, I got the following circuit with the indicated denominations, it is shown above.
This design of a simple voltage inverter is perfect for powering an energy-saving lamp with a power of 8,9,11 watts. Lamps with a power of 20 watts do not want to work, most likely the secondary is rather weak - I did not redo it. The 9-watt lamp shines as brightly as when powered directly from the 220V AC mains. The current consumption of the voltage converter circuit ranges from 0.5 - 0.54 Amperes.
Rice. 5. Appearance ready assembled device.
Rice. 6. Design dimensions in comparison.
Note: a pack of cigarettes is shown here for one purpose only - to show the comparative dimensions of the device.
Smoking is harmful!!
If you use the KT817 transistor and similar ones instead of the KT940 transistor, then the current consumed by the voltage inverter circuit and the lamp increases to 0.86 Ampere. This design of a simple voltage inverter is available for production by all radio amateurs and beginners. The advantages of this design are obvious: ease of manufacture and reliability in operation.
It should be noted that many radio amateurs live in rural areas and do not have the opportunity to purchase imported parts; moreover, although they are inexpensive, the same field-effect transistors cost money, which can immediately burn out or fail if there is an error, not to mention microcircuits.
Rice. 7. Connecting the voltage inverter to the battery and energy-saving lamp.
Rice. 8. Homemade voltage inverter in operation - the energy-saving lamp is burning brightly.
And most often, a rural radio amateur’s stock of radio components is limited to an old Soviet TV. This is how a simple voltage inverter appeared, assembled from parts obtained from Soviet trash. Having a battery with a capacity of 7 Ampere-Hours, it is not difficult to calculate how long it will last - I checked it personally.
From a Chinese gel battery with a capacity of 7 Ampere-Hours, the lamp burns at full brightness for 6 hours, and burns until the battery is almost completely discharged (voltage drops to 5.5 volts). The circuit starts reliably even when powered by 9 Volts. Everyone will find their own use for this design in everyday life.
We present a push-pull pulse converter assembled on the TL494 PWM controller. This makes the circuit quite simple and easy to repeat for many radio amateurs. At the output there are highly efficient rectifier diodes that double the voltage. You can also use a voltage converter without diodes - getting an alternating voltage. For example for electronic ballasts(when powered by LDS) constant pressure and the switching polarity is not relevant, since the ballast circuit has a diode bridge at the input. The schematic diagram is shown in the figure - click to enlarge.
The 12-220 V converter uses a ready-made high-frequency step-down transformer from the computer's AT or ATX power supply, but in our converter it will become a step-up transformer. Typically, these transformers differ only in size, and the location of the pins is identical. A non-working PC power supply can be found at any computer repair shop.
Operation of the circuit. Resistor R1 sets the pulse width at the output, R2 (together with C1) sets operating frequency. We reduce the resistance R1 - we increase the frequency. We increase the capacitance C1 - we reduce the frequency. We install powerful MOS field-effect transistors in the voltage converter, which are characterized by shorter response times and more simple circuits management. IRFZ44N, IRFZ46N, IRFZ48N work equally well here.
A radiator is not needed, since prolonged operation does not cause noticeable heating of the transistors. And if you still want to put them on a radiator, do not short-circuit the flanges of the transistor housings through the radiator! Use insulating gaskets and bushing washers from a computer power supply. However, for the first start, a radiator will not hurt; at least the transistors will not immediately burn out in the event of installation errors or a short circuit at the output.
Right assembled circuit The converter does not require adjustment. It is advisable to use a non-metallic housing to prevent high voltage breakdown on the housing. Be careful when working with the circuit, as 220 V voltage is dangerous!
Discuss the article CONVERTER 12-220
