Voltage regulators are widely used in everyday life and industry. Many people know such a device as a dimmer, which allows you to steplessly adjust the brightness of the lamps. It is an excellent example of a 220v voltage regulator. It is quite simple to assemble such a device with your own hands. Of course, you can buy it in the store, but the cost of a homemade product will be much lower.
Content
- Purpose and principle of operation
-
Manufacturing recommendations
- Triac based
- Thyristor based
Purpose and principle of operation
With the help of voltage regulators, you can change not only the brightness of the glow of incandescent lamps, but also the rotation speed of the electric motors, the temperature of the soldering iron tip etc. Often these devices are called power regulators, which is not entirely correct. Power control devices are based on PWM (Pulse Width Modulation) circuits.
This makes it possible to obtain at the output a different pulse repetition rate, the amplitude of which remains unchanged. However, if a voltmeter is connected in parallel to the load in such a circuit, then the voltage will also change. The fact is that the device simply does not have time to accurately measure the amplitude of the pulses.
Voltage regulators are most often made on the basis of semiconductor parts - thyristors and triacs. With their help, the duration of the passage of the voltage wave from the network to the load is changed.
It should be noted that voltage regulators will be most effective when working with resistive loads such as incandescent lamps. But using them to connect to an inductive load is impractical. The fact is that the indicator of inductive electric current is much lower in comparison with resistive one.
Manufacturing recommendations
Assembling a homemade dimmer is pretty simple. This will require some basic knowledge of electronics and a few details.
Triac based
Such a device works on the principle of the phase shift of the key opening. Below is the The simplest triac-based dimmer circuit:
Structurally, the device can be divided into two blocks:
- A power switch, in the role of which a triac is used.
- Node for creating control pulses based on a symmetrical dynistor.
A voltage divider is created using resistors R1-R2. Please note that the resistance R1 is variable. This allows you to change the voltage on the line R2-C1. A DB3 dinistor is connected between these elements. As soon as the voltage on the capacitor C1 reaches the value of the opening threshold of the dinistor, a control pulse is applied to the key (triac VS1).
As a result, the power switch turns on, and an electric current begins to pass through it to the load. The position of the regulator determines in which part of the wave phase the power switch should work.
Thyristor based
These partings are also quite effective, and their circuits are not very complex. The role of the key in such a device is performed by a thyristor. If you carefully study the circuit of the device, you can immediately notice the main difference of this circuit from the previous one - for each half-wave, its own key with a control dinistor is used.
The principle of operation of a thyristor device is as follows:
- When a positive half-wave passes through the R5-R4-R3 line, the capacitor C1 is charged.
- After reaching the switching threshold of the V3 dinistor, it is triggered, and the electric current is supplied to the V1 key.
- With the passage of the negative half-wave, a similar situation is observed for the R1-R2-R5 line, the V4 control dinistor and the V2 key.
With the help of phase controllers, you can control not only the brightness of incandescent lamps, but also other types of loads, for example, the number of revolutions of a drill. However, it should be remembered that a thyristor-based device cannot be used to work with LED and fluorescent lamps.
Also, capacitor regulators are used in everyday life. However, unlike semiconductor devices, they do not allow smooth voltage changes. Thus, for DIY making it is best suitable thyristor and triac circuits.
Finding all the parts necessary for making the regulator is not difficult. At the same time, it is not necessary to buy them, but you can drop them out of an old TV or other radio equipment. If desired, based on the selected circuit, you can make a printed circuit board, and then solder all the elements into it. Also, parts can be connected with ordinary wires. The home craftsman can choose the method that seems most attractive to him.
Both devices reviewed are fairly easy to assemble, and you do not need to have serious knowledge of electronics to complete all the work. Even a novice radio amateur will be able to make a 220v voltage regulator circuit with his own hands. At a low cost, they are practically in no way inferior to factory counterparts.
