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220 volts from the battery at 37 V

In everyday life, we most often encounter power supplies that lower the high voltage in the network to several volts, which are necessary to connect various devices. However, you can do the inverse transformation. Moreover, the scheme is completely uncomplicated.
It can come in handy in two cases:
  • In order to connect equipment and devices that are powered from only 220 volts in the field.
  • In case of power outages.

Well, do not forget that experimenting is always entertaining. For example, I assembled this design simply out of interest, without an aim for practical application.
True, it should be noted that the presented converter is of low power and will not withstand a large load, such as a TV. However, as will be seen in the example, an energy-saving light bulb works from it.

Transducer Fabrication


We need only a few details:
  • Transformer from an old phone charger.
  • Transistor 882P or its domestic analogues KT815, KT817.
  • Diode IN5398, an analogue of KD226 or any other one designed for reverse current up to 10 volts of medium or high power.
  • Resistor (resistance) at 1 kOhm.
  • Small breadboard.

Naturally, you will need a soldering iron with solder and flux, wire cutters, wires and a multimeter (tester). You can, of course, make a printed circuit board, but for a circuit of several details, you should not waste time developing track layouts for their drawing and etching of foil textolite or getinaks. We check the transformer. The board of the old charger.
220 volts from a 3.7 V battery

The soldered transformer.
220 volts from a 3.7 V battery

Next, we need to check the transformer and find the conclusions of its windings. We take a multimeter, switch it to ohmmeter mode. In turn, we check all the conclusions, we find those that are a couple of "call" and record their resistance.
1. The first 0.7 Ohm.
220 volts from a 3.7 V battery

2. The second is 1.3 ohms.
220 volts from a 3.7 V battery

3. The third is 6.2 ohms.
220 volts from a 3.7 V battery

That winding, in which the greatest resistance was primary, 220 V was supplied to it. In our device it will be secondary, that is, an output. The rest was relieved undervoltage. With us, they will serve as the primary (the one with a resistance of 0.7 ohms) and part of the generator (with a resistance of 1.3). The measurement results for different transformers may vary, you need to focus on their relationship between each other.

Device diagram


Converter circuit

As you can see, it is the simplest. For convenience, we marked the resistance of the windings. The transformer cannot convert direct current. Therefore, a generator is assembled on the transistor and one of its windings. It supplies a pulsating voltage from the input (battery) to the primary winding, a voltage of about 220 volts is removed from the secondary.

We assemble the converter


We take a breadboard.
220 volts from a 3.7 V battery

We install a transformer on it. Choose a resistor of 1 kilo-ohm. We insert it into the holes of the board, next to the transformer. We bend the terminals of the resistor so as to connect them with the corresponding contacts of the transformer. Solder it. At the same time, it is convenient to fix the board in any clamp, as in the photo, so that the problem of the missing "third hand" does not arise. Soldered resistor.We bite the extra length of the output. A board with bitten resistor leads. Next we take the transistor. We install it on the board on the other side of the transformer, as in the screenshot (I selected the locations of the parts so that it is more convenient to connect them according to the circuit diagram). We bend the transistor leads. Solder them. Installed transistor. Take a diode. We install it on the board parallel to the transistor. We solder. Our scheme is ready.
220 volts from a 3.7 V battery

220 volts from a 3.7 V battery

Solder the wires to connect a constant voltage (DC input). And wires for pulsating high voltage (AC output).
220 volts from a 3.7 V battery

For convenience, we take 220 volt wires with crocodiles.
220 volts from a 3.7 V battery

Our device is ready.

Testing the converter


In order to apply voltage, we select a 3-4 volt battery. Although you can use any other power source.
220 volts from a 3.7 V battery

Solder the low voltage input wires to it, observing the polarity. We measure the voltage at the output of our device. It turns out 215 volts.
220 volts from the battery at 37 V

Attention. It is not advisable to touch the parts when the power is connected. This is not so dangerous if you have no health problems, especially with your heart (although two hundred volts, but the current is weak), but it can be unpleasant to “pinch”.
We complete the test by connecting a 220 volt fluorescent energy-saving lamp. Thanks to the "crocodiles" this is easy to do without a soldering iron. As you can see, the lamp is on.
220 volts from the battery at 37 V

Our device is ready.
Tip. You can increase the power of the converter by installing a transistor on the radiator.
True battery capacity is not enough for long. If you are going to constantly use the converter, then select a more capacious battery and make a case for it.

Watch the video


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Comments (12)
  1. Guest Michael
    #1 Guest Michael Guests April 8, 2018 08:53
    6
    and the TV \ small \ will work
  2. Guest Vlad
    #2 Guest Vlad Guests April 10, 2018 9:23 p.m.
    0
    no
  3. Alexey
    #3 Alexey Guests April 11, 2018 08:01
    0
    And what kind of power will it have?
  4. name
    #4 name Guests April 11, 2018 12:28
    1
    220v you received, but there is no 50Hz for any other equipment except light bulbs
    1. Alexey
      #5 Alexey Guests April 12, 2018 15:30
      0
      Modern pulse technology does not give a damn about 50Hz. At least feed her constantly. The main thing that 320v was a constant component.
      1. Alexey
        #6 Alexey Guests April 14, 2018 00:25
        2
        A popular fallacy. At the input of almost all switching power supplies are diode bridges, often dialed on 1n4007 diodes. CCL in the picture is no exception. Look at their characteristics: they are not designed for high frequencies, and they can easily make a bang. Do you need it !? If you do not want to ditch your equipment - do not use such homemade products!
        As an option to get out of the situation, I can propose putting a rectifier on fast diodes at the output of the described device, for example, FR106. In this case, the input diode bridge of the powered equipment will not be overloaded.
        Yes, and again: most modern battery chargers for phones are made using the flyback converter circuitry, and if you get a “transformer” from there, it will be a mistake: in such sources a transformer rather than a multi-winding inductor is used. In appearance, it can be impossible to distinguish them, but there are radical differences in use, and your homemade product will either not start, or it will not be able to give out any useful power.
  5. Guest Andrey
    #7 Guest Andrey Guests April 11, 2018 13:53
    4
    the diagram shows a transistor of the n-p-n structure, this is an error. p-n-p is needed for the circuit to work.
    or change the polarity of the power, and the polarity of the diode.
    1. Guest Vadim
      #8 Guest Vadim Guests April 24, 2018 02:11
      0
      also noticed
  6. Colin
    #9 Colin Guests April 14, 2018 10:02 p.m.
    1
    What a primitive!) We did it in the last century! Trans from the charger? So, so the power will be 5 watts.
  7. Placid
    #10 Placid Guests April 16, 2018 13:26
    0
    You can do it, but why? In my opinion, it is only necessary to make craftsmanship that either is not manufactured commercially or that surpasses factory products in terms of parameters. Well, buy a penny Chinese watt inverter for as much as you need. Ask acquaintances to take an interest in a written-off uninterruptible device at work at computer specialists (in many offices they do not change the batteries in them, but simply buy new devices). Threat I have designed or repeated a lot of things.
  8. Max
    #11 Max Guests November 6, 2018 06:51
    0
    I assembled this device on n-p-n as in the diagram, of course, it did not work. Delivered p-n-p B772, the diode 207 works, but 440-450v gives a couple of many. Who can tell what I did wrong?
  9. Guest Pavel
    #12 Guest Pavel Guests December 23, 2018 20:48
    0
    the voltage is so low at the output that it doesn’t even light the LED lamp, and the housekeeper just blinks

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