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12 volt powerful homemade power supplies. Power Supply

Many electrical devices are powered by constant voltage 12 volts. If such a technique does not particularly need high voltage stability, then the simplest power supply, consisting of a step-down transformer, is quite suitable. diode bridge and an electrolyte filter capacitor. Here the question remains only for the power of such a power source, and therefore it depends on it which functional parts will be in the 12 volt power supply. In this article, let's take a closer look at this topic.

So, the circuit of a simple 12 volt power supply begins with a step-down transformer, the task of which is to lower the mains alternating voltage of 220 volts to a lower one. It is logical to assume that this reduced voltage should in our case be 12 volts. But no. At the exit secondary winding transformer, to get a constant 12 volts as a result, there should be about 10 volts. Why is that? It's just that there is such an effect in electrical engineering - the alternating voltage after the diode bridge has a rectified current, but it is spasmodic. When we connect an electrolyte filter capacitor to the output of the bridge, these DC voltage surges are smoothed out, and the voltage itself increases by about 18%. So it turns out that the alternating 10 volts after the rectifier bridge and the filtering capacitor of the electrolyte will turn into constant 12 volts.

We need to decide, first of all, with the power of our 12 volt power supply. What is the maximum current strength we want it to have. For example, you need to have a maximum current of 5 amperes. In this case, in order to solder a good 12 volt power supply with this current, we need a step-down transformer with a power of about 80 watts. Let me remind you that to find the electric power you need to multiply the current by the voltage. Therefore, we multiply our 12 volts by 5 amperes and get 60 watts. Plus, we add a small margin to this (let it be 20 watts). So we see that we need an 80 watt transformer (this is if we follow the optimal path, although if you put more power on the trance, this will only affect the overall dimensions of the power source).

To obtain a current on the secondary winding of about 5 amperes, the diameter of this very winding must be at least 1.6 mm (copper). To determine the dependence of the diameter of the secondary winding wire and the current strength that it should provide, you need to look at the reference tables (they are easy to find on the Internet using the search).

Now you need to choose a suitable rectifier diode bridge, which will allow us to make a constant voltage from an alternating voltage, albeit in an abrupt form. Again, you need to first determine the current strength that the diode bridge can withstand without negative effects on it. We decided that we need a maximum current of 5 amperes. As in the case of the transformer, let's add some margin to this. As a result, we find a diode bridge (diodes under it) for a current strength of 8-10 amperes. The bridge must be rated at least 12 volts (although diodes with low reverse voltage are rare, they are usually rated for large enough reverse voltages). Either we put a ready-made integral diode bridge, or we solder it ourselves from four diodes with the necessary parameters.

Well, the last important functional element of our homemade 12 volt power supply, which we will solder with our own hands, is the electrolyte capacitor. It performs a filtering role, smoothing out DC voltage surges, making the DC voltage more even (though not ideal). For our power supply, an electrolyte capacitor is quite suitable, designed for a voltage of 16-25 volts and a capacity of about 5,000 - 10,000 microfarads. That's all, it remains only to solder all these components into a single circuit and assemble them in a suitable case.

Video on this topic:

P.S. For convenience, when using such a simple, home-made 12-volt power supply, it would be nice to put a digital voltmeter and ammeter module in it. This will allow you to see the voltage drop and the strength of the current consumed during operation. Such digital indicator modules that measure direct current and voltage are quite cheap (about 3 bucks). I ordered such a module for myself by sending it from China. It is compact, precise and convenient. So I advise.

A rectifier is a device for converting AC voltage to DC. This is one of the most common parts in electrical appliances, ranging from hair dryers to all types of power supplies with output voltage. direct current. There are different schemes of rectifiers, and each of them copes with its task to a certain extent. In this article we will talk about how to make a single-phase rectifier, and why you need it.

Definition

A rectifier is a device that converts AC to DC. The word "constant" is not entirely correct, the fact is that at the output of the rectifier, in the sinusoidal alternating voltage circuit, in any case, there will be an unstabilized pulsating voltage. In simple words: constant in sign but varying in magnitude.

There are two types of rectifiers:

half wave. It rectifies only one half-wave of the input voltage. Strong ripples and low relative to the input voltage are characteristic.

full wave. Accordingly, two half-waves are straightened. The ripple is lower, the voltage is higher than at the rectifier input - these are the two main characteristics.

What does stabilized and unstabilized voltage mean?

A stabilized voltage is a voltage that does not change in magnitude regardless of either the load or the input voltage surges. For transformer power supplies, this is especially important, because the output voltage depends on the input voltage and differs from it by Ktransformation times.

Unstabilized voltage - varies depending on surges in the supply network and load characteristics. With such a power supply, due to drawdowns, the connected devices may malfunction or be completely inoperable and fail.

Output voltage

The main values \u200b\u200bof alternating voltage are the amplitude and effective value. When they say "in the 220V network, there are changes" they mean the operating voltage.

If they talk about the amplitude value, then they mean how many volts are from zero to the top point of the half-wave of the sinusoid.

Omitting the theory and a number of formulas, we can say that 1.41 times less than the amplitude. Or:

The amplitude voltage in the 220V network is:

The first scheme is more common. It consists of a diode bridge - interconnected by a "square", and a load is connected to its shoulders. The bridge type rectifier is assembled according to the diagram below:

It can be connected directly to a 220V network, as done in, or to the secondary windings of a mains (50 Hz) transformer. Diode bridges according to this scheme can be assembled from discrete (separate) diodes or you can use a ready-made assembly of a diode bridge in a single package.

The second circuit - a mid-point rectifier cannot be connected directly to the network. Its meaning is to use a transformer with a tap from the middle.

In essence, these are two half-wave rectifiers connected to the ends of the secondary winding, the load is connected with one contact to the junction point of the diodes, and the second - to the tap from the middle of the windings.

Its advantage over the first circuit is a smaller number of semiconductor diodes. And the disadvantage is the use of a transformer with a midpoint or, as they also call it, a tap from the middle. They are less common than conventional non-tapped secondary transformers.

Ripple smoothing

Power supply with pulsating voltage is unacceptable for a number of consumers, for example, light sources and audio equipment. Moreover, the permissible light pulsations are regulated in state and industry regulations.

To smooth out ripples, they use a parallel-mounted capacitor, an LC filter, various P- and G-filters ...

But the most common and simplest option is a capacitor installed in parallel with the load. Its disadvantage is that in order to reduce ripples on a very powerful load, it will be necessary to install capacitors of a very large capacity - tens of thousands of microfarads.

Its principle of operation is that the capacitor is charged, its voltage reaches an amplitude, the supply voltage after the point of maximum amplitude begins to decrease, from that moment the load is powered by the capacitor. The capacitor discharges depending on the resistance of the load (or its equivalent resistance if it is not resistive). The larger the capacitance of the capacitor, the smaller the ripple will be, when compared with a capacitor with a smaller capacitance connected to the same load.

In simple words: the slower the capacitor discharges, the less ripple.

The discharge rate of the capacitor depends on the current drawn by the load. It can be determined by the time constant formula:

where R is the load resistance and C is the capacitance of the smoothing capacitor.

Thus, from a fully charged state to a fully discharged capacitor, it will be discharged in 3-5 t. It charges at the same rate if the charge occurs through a resistor, so in our case it does not matter.

It follows from this that in order to achieve an acceptable level of ripple (it is determined by the requirements of the load on the power source), a capacitance is needed that will be discharged in a time many times greater than t. Since the resistances of most loads are relatively small, a large capacitance is needed, therefore, in order to smooth out ripples at the output of the rectifier, they are used, they are also called polar or polarized.

Please note that it is highly not recommended to confuse the polarity of an electrolytic capacitor, because this is fraught with its failure and even explosion. Modern capacitors are protected from explosion - they have top cover there is a stamping in the form of a cross, along which the case is simply cracked. But a jet of smoke will come out of the condenser, it will be bad if it gets into your eyes.

The capacitance is calculated based on what ripple factor needs to be provided. To put it plain language, then the ripple coefficient shows by what percentage the voltage sags (pulses).

C=3200*In/Un*Kp,

Where In is the load current, Un is the load voltage, Kn is the ripple factor.

For most types of equipment, the ripple factor is taken as 0.01-0.001. Additionally, it is desirable to install as large a capacitance as possible to filter out high-frequency interference.

How to make a power supply with your own hands?

The simplest DC power supply consists of three elements:

1. Transformer;

3. Capacitor.

This is an unregulated DC power supply with a smoothing capacitor. The voltage at its output is greater than the alternating voltage of the secondary winding. This means that if you have a 220/12 transformer (primary at 220V and secondary at 12V), then you will get 15-17V DC at the output. This value depends on the capacitance of the smoothing capacitor. This circuit can be used to power any load, if it does not matter to it that the voltage can “float” with changes in the mains voltage.

A capacitor has two main characteristics - capacitance and voltage. We figured out how to select the capacitance, but not with the selection of voltage. The voltage of the capacitor must exceed the amplitude voltage at the output of the rectifier by at least half. If the actual voltage on the capacitor plates exceeds the nominal voltage, there is a high probability of its failure.

Old Soviet capacitors were made with a good voltage margin, but now everyone uses cheap electrolytes from China, where at best there is a small margin, and at worst, it will not withstand the specified nominal voltage. So don't skimp on reliability.

A stabilized power supply differs from the previous one only in the presence of a voltage (or current) stabilizer. The simplest option- use L78xx or others, such as domestic ROOL.

So you can get any voltage, the only condition when using such stabilizers is that the voltage to the stabilizer must exceed the stabilized (output) value by at least 1.5V. Consider what is written in the 12V datasheet of the L7812 stabilizer:

The input voltage should not exceed 35V, for stabilizers from 5 to 12V, and 40V for stabilizers at 20-24V.

The input voltage should exceed the output voltage by 2-2.5V.

Those. for a stabilized 12V power supply with an L7812 series stabilizer, it is necessary that the rectified voltage lies within 14.5-35V to avoid drawdowns, it would be an ideal solution to use a transformer with a 12V secondary winding.

But the output current is quite modest - only 1.5A, it can be amplified using a pass transistor. If you have , you can use this scheme:

It shows only the connection of a linear stabilizer. The "left" part of the circuit with a transformer and a rectifier is omitted.

If you have NPN transistors like KT803 / KT805 / KT808, then this one will do:

It is worth noting that in the second circuit, the output voltage will be less than the stabilization voltage by 0.6V - this is a drop at the emitter-base junction, we wrote more about this. To compensate for this drop, a diode D1 was introduced into the circuit.

It is possible to install two linear stabilizers in parallel, but it is not necessary! Due to possible deviations in manufacturing, the load will be unevenly distributed and one of them may burn out because of this.

Install both the transistor and the linear regulator on a heatsink, preferably on separate heatsinks. They get very hot.

Regulated power supplies

The simplest adjustable power supply can be made with an adjustable linear stabilizer LM317, its current is also up to 1.5 A, you can amplify the circuit with a pass transistor, as described above.

Here is a more visual diagram for assembling an adjustable power supply.

With a thyristor regulator in the primary winding, essentially the same regulated power supply.

By the way, a similar scheme regulates the welding current:

Conclusion

A rectifier is used in power supplies to produce direct current from alternating current. Without his participation, it will not be possible to power a DC load, for example led strip or radio.

Also used in a variety of chargers for car batteries, there are a number of circuits using a transformer with a group of taps from primary winding, which are switched by a biscuit switch, and only a diode bridge is installed in the secondary winding. The switch is installed on the high voltage side, since the current is several times lower there and its contacts will not burn from this.

According to the diagrams from the article, you can assemble the simplest block nutrition as for permanent job with some kind of device, and for testing their electronic homemade products.

The circuits do not have high efficiency, but they produce a stabilized voltage without much ripple, you should check the capacitance of the capacitors and calculate for a specific load. They are perfect for low-power audio amplifiers, and will not create additional background. An adjustable power supply will be useful for motorists and auto electricians to test the generator voltage regulator relay.

An adjustable power supply is used in all areas of electronics, and if it is improved with short-circuit protection or a current stabilizer on two transistors, then you will get an almost complete laboratory block nutrition.

At present, feeding block systems are the main part of lighting devices. It is the 12-volt power supply that saves electrical energy. Making the device is easy. In our article we will try to answer the question of how to do.

Power supply types

It is customary to divide feeding systems into several types. The first group includes secondary power supplies, which a large number of. In the second - transformer or network. The third group includes impulse sources. Each of the power supplies has its own characteristics, its positive and negative sides.

The main part of lighting devices is the recharge system. It is the 12-volt power supply that saves electrical energy. Making the device is easy. In our article we will try to answer the question of how to make a power supply with your own hands.

The most common is the feed system of the second type, which we will assemble today.

Components of the device

The mechanism we are assembling today consists of three parts:

step-down transformer, which is the most important and integral part;
a capacitor with which the current voltage is stabilized to optimal readings;
diodes, which are necessary for assembling a diode bridge with your own hands.

Each of the parts is very important. If in any of them an error is made during assembly, this will lead to the fact that the assembled unit and the household electrical appliance connected to the system will not work correctly. And also the assembled device may not turn on at all. Let's consider each of the components of the mechanism in more detail.

Transformer selection

The voltage converter is one of the main transformer components. Here, the alternating 220-volt voltage is converted into a similar one, but with a slightly reduced amplitude.

Using simple calculations, we find out how many revolutions the secondary winding made around its axis. Having learned the number of revolutions (usually the voltage indicator in this case is 6.3), you should divide the volt indicator by the number of turns.

An ordinary step-down device, necessary to reduce the voltage from the usual 220 volts to 12 volts, can be used as a transformer-type machine.

It is optimal to take a 470 microfarad capacitor with a 25-volt voltage for the device. Why would it be the best option? This is due to the fact that when the voltage leaves the unit, it becomes higher than the standard voltage of 12V. When the mechanism starts to work, the voltage returns to standard values (12 V).

How to make a rectifier

A device operating on semiconductor diodes is called a rectifier, which is one of the important elements of the power supply circuit. With the help of a rectifier, the values \u200b\u200bof alternating current are converted, bringing them closer to its constant indicators.

It is not difficult to assemble a 12 volt power supply with your own hands. First of all, you should learn that the capacitor has two outputs: one of them is positive, the other is negative.

How to understand where is which one? If the diode has a positive value, then there is a special strip on it, if there is no strip, then the diode has a negative value. The diode components are connected in series:

Schematic connection of 2 elements: the device with a minus must be connected to a diode with a positive value.

In a similar way, the connection of 2 other diodes takes place (the device with a minus must be connected to the diode with a positive value). The connection of paired structures with each other, while it is necessary to connect diodes in pairs (negative with a negative indicator, and positive with a positive one).

It is important to ensure that the connection is correct, otherwise it will lead to problems in the operation of the mechanism.

After creating a diode bridge with 4 connection points:

two with a plus or minus circuit;
one plus-plus;
one minus-minus - you can start assembling the mechanism. It is important to check the quality of the contact between the diode systems.

Assembly of filtration blocks

Before connecting a 12 volt power supply, it is recommended to install special filters that will help the work of those connected to the device. household appliances. To fuel Appliances, the LC chain is usually used. Where a rectifier with a plus value exits the device, a choke must be connected. It must pass through electric current.

At the second stage of filtration, work is carried out with an electrolytic capacitor with a large capacity, which should be connected to the inductor from the side that has a positive value.

The connection of the second output goes to a common electrical wire with a minus value. An electrolytic capacitor helps stabilize the electric current. How does it happen? We will consider this issue in a little more detail.

How to stabilize the output voltage

To stabilize the output voltage, you can use a zener diode that has the strength of a 12-volt indicator. Even if you install more powerful stabilizers, then the same 12 volts are obtained at the output.

Where does the rest go? The rest is converted into thermal energy, so this component is usually mounted on the surface of the radiator.

Regulatory process

It is common to use regulated power supplies. When installing the stabilizer, it is necessary to mount a special wire to which a variable resistor should be connected.

The variable resistor and output of the assembly has 220 ohm resistance values. A semiconductor diode is installed at the input and output of the stabilizing device.

The regulator allows you to stabilize the current indicators to optimal values, prevents the mechanism from burning out. To enhance the safety of the assembled unit, you can install an electronic voltmeter at the outlet of the system, which will help monitor the indicators of the current voltage in the system.

Assembling a 12 volt power supply is not difficult even for a person with minimal knowledge in the field of assembling any devices. To do this, you can use the step-by-step instructions with a photo at each stage. With the necessary details and step by step instructions, you can assemble any mechanism.

When connecting to electrical appliances, it is necessary to consult a master electrician who will review the correct assembly, which will prevent problems with the operation of the device.

Photo of power supplies for 12 volts

How to assemble a simple power supply and a powerful voltage source yourself.
Sometimes you have to connect different electronic devices, including home-made ones, to a 12 volt DC source. The power supply is easy to assemble on your own during half a day off. Therefore, there is no need to purchase a ready-made block, when it is more interesting to make the necessary thing for your laboratory yourself.

Anyone who wants to be able to make a 12-volt unit on their own, without much difficulty.
Someone needs a source to power the amplifier, and someone needs to power a small TV or radio ...
Step 1: What parts are needed to assemble the power supply...
To assemble the block, prepare in advance the electronic components, parts and accessories from which the block itself will be assembled....
-Circuit board.
- Four diodes 1N4001, or similar. Diode bridge.
- Voltage stabilizer LM7812.
- Low-power step-down transformer for 220 V, the secondary winding should have 14V - 35V AC voltage, with a load current of 100 mA to 1A, depending on how much power you need to get at the output.
- Electrolytic capacitor with a capacity of 1000uF - 4700uF.
- 1uF capacitor.
-Two 100nF capacitors.
- Cut wires.
- Radiator, if needed.
If you need to get the maximum power from the power supply, you need to prepare the appropriate transformer, diodes and heatsink for the chip.
Step 2: Tools....
For the manufacture of the block, tools for installation are required:
-Soldering iron or Soldering Station
-Nippers
- Mounting tweezers
-Wire strippers
- Solder suction device.
-Screwdriver.
And other tools that you might find useful.
Step 3: Schematic and more...

To get a 5 volt stabilized power supply, you can replace the LM7812 stabilizer with the LM7805.
To increase the load capacity of more than 0.5 amperes, you need a heatsink for the microcircuit, in otherwise it will fail from overheating.
However, if you need to get a few hundred milliamps (less than 500 mA) from the source, then you can do without a heatsink, heating will be negligible.
In addition, an LED is added to the circuit to visually verify that the power supply is working, but you can do without it.

Power supply circuit 12v 30A.
When using one 7812 stabilizer as a voltage regulator and several powerful transistors, this block power supply is capable of providing an output load current of up to 30 amperes.
Perhaps the most expensive part of this circuit is the power step-down transformer. The voltage of the secondary winding of the transformer must be a few volts more than the stabilized voltage of 12V in order to ensure the operation of the microcircuit. It must be borne in mind that one should not strive for a larger difference between the input and output voltage values, since at such a current the heat sink of the output transistors increases significantly in size.
In the transformer circuit, the diodes used must be designed for a large maximum forward current, approximately 100A. The maximum current flowing through the 7812 chip in the circuit will not exceed 1A.
Six composite Darlington type TIP2955 transistors connected in parallel provide a load current of 30A (each transistor is rated for a current of 5A), such a large current requires an appropriate size of the radiator, each transistor passes through itself one sixth of the load current.
A small fan can be used to cool the radiator.
Checking the power supply
When you first turn it on, it is not recommended to connect the load. We check the operation of the circuit: we connect a voltmeter to the output terminals and measure the voltage, it should be 12 volts, or the value is very close to it. Next, we connect a load resistor of 100 ohms, with a dissipation power of 3 W, or a similar load - such as an incandescent lamp from a car. In this case, the voltmeter reading should not change. If there is no 12 volt voltage at the output, turn off the power and check the correct installation and serviceability of the elements.
Before installation, check the serviceability of the power transistors, since with a broken transistor, the voltage from the rectifier goes directly to the output of the circuit. To avoid this, check the power transistors for a short circuit, to do this, measure the resistance between the collector and emitter of the transistors separately with a multimeter. This check must be carried out before installing them in the circuit.

Power supply 3 - 24v

The power supply circuit produces an adjustable voltage in the range from 3 to 25 volts, with a maximum load current of up to 2A, if you reduce the current-limiting resistor of 0.3 ohms, the current can be increased to 3 amperes or more.
Transistors 2N3055 and 2N3053 are installed on the corresponding heatsinks, the power of the limiting resistor must be at least 3 watts. Voltage regulation is controlled by the LM1558 or 1458 op amp. When using the 1458 op amp, it is necessary to replace the stabilizer elements that supply voltage from pin 8 to 3 op amps from a divider with 5.1 K resistors.
The maximum constant voltage for supplying the op-amps 1458 and 1558 is 36 V and 44 V, respectively. The power transformer must deliver at least 4 volts more than the stabilized output voltage. The power transformer in the circuit has an output voltage of 25.2 volts AC with a tap in the middle. When switching the windings, the output voltage decreases to 15 volts.

1.5 V power supply circuit

The power supply circuit for obtaining a voltage of 1.5 volts uses a step-down transformer, a bridge rectifier with a smoothing filter and an LM317 chip.

Regulated power supply circuit from 1.5 to 12.5 V

A power supply circuit with output voltage regulation to obtain a voltage from 1.5 volts to 12.5 volts, the LM317 microcircuit is used as a regulatory element. It must be installed on the radiator, on an insulating gasket to prevent a short circuit to the case.

Fixed Output Voltage Power Supply Diagram

Power supply circuit with a fixed output voltage of 5 volts or 12 volts. As active element the LM 7805, LM7812 microcircuit is used; it is installed on a radiator to cool the heating of the case. The choice of transformer is shown on the left side of the plate. By analogy, you can make a power supply for other output voltages.

20 watt power supply circuit with protection

The circuit is for a small homemade transceiver by DL6GL. When developing the unit, the task was to have an efficiency of at least 50%, a nominal supply voltage of 13.8V, a maximum of 15V, for a load current of 2.7A.
According to what scheme: switching power supply or linear?
Switching power supplies turn out to be small-sized and the efficiency is good, but it is not known how it will behave in a critical situation, output voltage surges ...
Despite the shortcomings, a linear control scheme was chosen: a sufficiently large transformer, not high efficiency, cooling is necessary, etc.
Used parts from a homemade power supply from the 1980s: a heatsink with two 2N3055s. The only thing missing was the µA723/LM723 voltage regulator and a few small parts.
The voltage regulator is assembled on a µA723 / LM723 chip in standard inclusion. Output transistors T2, T3 type 2N3055 are mounted on radiators for cooling. Using the potentiometer R1, the output voltage is set within 12-15V. Using the variable resistor R2, the maximum voltage drop across the resistor R7 is set, which is 0.7V (between pins 2 and 3 of the microcircuit).
A toroidal transformer is used for the power supply (it can be any at your discretion).
On the MC3423 chip, a circuit is assembled that is triggered when the voltage (emissions) at the output of the power supply is exceeded, by adjusting R3, the voltage threshold on pin 2 is set from the divider R3 / R8 / R9 (2.6V reference voltage), voltage is supplied from output 8 to open the thyristor BT145, causing a short circuit leading to the operation of the fuse 6.3a.

To prepare the power supply for operation (fuse 6.3a is not involved yet), set the output voltage, for example, 12.0V. Load the block with a load, for this you can connect halogen lamp 12V/20W. Set R2 so that the voltage drop is 0.7V (the current must be within 3.8A 0.7 = 0.185Ωx3.8).
We configure the operation of overvoltage protection, for this we smoothly set the output voltage to 16V and adjust R3 to actuate the protection. Next, we set the output voltage to normal and install the fuse (before that, we put a jumper).
The described power supply can be reconstructed for more powerful loads, for this, install a more powerful transformer, additional transistors, strapping elements, a rectifier at your discretion.

Homemade 3.3v power supply

If you need a powerful power supply, 3.3 volts, then it can be made by redoing old block power supply from a PC or using the above diagrams. For example, in a 1.5 V power supply circuit, replace a 47 ohm resistor of a higher rating, or put a potentiometer for convenience, adjusting it to the desired voltage.

Transformer power supply on KT808

Many radio amateurs still have old Soviet radio components that are lying around idle, but which can be successfully applied and they will serve you faithfully for a long time, one of the well-known UA1ZH circuits that walks around the Internet. Many spears and arrows have been broken on the forums when discussing what is better than a field-effect transistor or an ordinary silicon or germanium one, what temperature of crystal heating they can withstand and which one is more reliable?
Each side has its own arguments, but you can get the parts and make another simple and reliable power supply. The circuit is very simple, it is protected from overcurrent and, when three KT808s are connected in parallel, it can deliver a current of 20A, the author used such a block with 7 parallel transistors and gave 50A to the load, while the capacitance of the filter capacitor was 120,000 microfarads, the voltage of the secondary winding was 19v. It must be taken into account that the relay contacts must switch such a large current.

With proper installation, the output voltage drawdown does not exceed 0.1 volts

Power supply for 1000v, 2000v, 3000v

If we need to have a high voltage constant voltage source to power the lamp of the transmitter output stage, what should we use for this? There are many different power supply circuits for 600v, 1000v, 2000v, 3000v on the Internet.
First: for high voltage, circuits are used from transformers for both one phase and three phases (if there is a three-phase voltage source in the house).
Second: to reduce the size and weight, a transformerless power supply circuit is used, directly a 220 volt network with voltage multiplication. The biggest drawback of this circuit is that there is no galvanic isolation between the network and the load, as the output is connected to this voltage source, observing the phase and zero.

The circuit has a step-up anode transformer T1 (for the required power, for example, 2500 VA, 2400V, current 0.8 A) and a step-down incandescent transformer T2 - TN-46, TN-36, etc. To eliminate current surges when switching on and protecting diodes when charging capacitors, switching on through quenching resistors R21 and R22 is used.
The diodes in the high-voltage circuit are shunted by resistors in order to evenly distribute Uobr. Calculation of the nominal value according to the formula R (Ohm) \u003d PIVx500. C1-C20 to eliminate white noise and reduce surges. Bridges of the KBU-810 type can also be used as diodes by connecting them according to the indicated scheme and, accordingly, taking the required amount, not forgetting about shunting.
R23-R26 for discharging capacitors after a power outage. To equalize the voltage on series-connected capacitors, equalizing resistors are placed in parallel, which are calculated from the ratio for every 1 volt there are 100 ohms, but with high voltage the resistors are obtained with a sufficiently large power and here you have to maneuver, taking into account that the open circuit voltage is 1.41 more.