Today, many devices are made with the ability to adjust the current. Thus, the user has the ability to control the power of the device. These devices can work in a network with alternating current, as well as direct current. In their design, the regulators are quite different. The main part of the device can be called thyristors.
Resistors and capacitors are also integral elements of regulators. Magnetic amplifiers are used only in high voltage devices. The smoothness of adjustment in the device is ensured by the modulator. Most often you can find just their rotary modifications. Additionally, the system has filters that help smooth out noise in the circuit. Due to this, the current at the output is more stable than at the input.
Scheme of a simple regulator
The current regulator circuit of the conventional type of thyristors involves the use of diode ones. Today, they are characterized by increased stability and are able to serve for many years. In turn, the triodeanalogues can boast of their efficiency, however, they have little potential. For good current conductivity, field-type transistors are used. A wide variety of boards can be used in the system.
In order to make a 15 V current regulator, you can safely choose a model marked KU202. The blocking voltage is supplied by capacitors that are installed at the beginning of the circuit. Modulators in regulators, as a rule, are of rotary type. By their design, they are quite simple and allow you to change the current level very smoothly. In order to stabilize the voltage at the end of the circuit, special filters are used. Their high-frequency analogues can only be installed in regulators over 50 V. They cope with electromagnetic interference quite well and do not give a large load on thyristors.
DC Devices
The constant current regulator circuit is characterized by high conductivity. At the same time, heat losses in the device are minimal. To make a DC regulator, a thyristor requires a diode type. The impulse supply in this case will be high due to the fast voltage conversion process. The resistors in the circuit must be able to handle a maximum resistance of 8 ohms. In this case, this will minimize heat loss. Ultimately, the modulator will not overheat quickly.
Modern analogues are designed for approximately a maximum temperature of 40 degrees, and this should be taken into account. fieldTransistors can only carry current in a circuit in one direction. Given this, they must be located in the device behind the thyristor. As a result, the level of negative resistance will not exceed 8 ohms. High-pass filters are rarely installed on a DC regulator.
AC models
The alternating current regulator is different in that the thyristors in it are used only of the triode type. In turn, transistors are commonly used field-type. Capacitors in the circuit are used only for stabilization. It is possible, but rare, to meet high-frequency filters in devices of this type. High temperature problems in models are solved by a pulse converter. It is installed in the system behind the modulator. Low-pass filters are used in regulators with power up to 5 V. Cathode control in the device is carried out by suppressing the input voltage.
Stabilization of the current in the network occurs smoothly. In order to cope with high loads, reverse zener diodes are used in some cases. They are connected by transistors using a choke. In this case, the current regulator must be able to withstand a maximum load of 7 A. In this case, the limiting resistance level in the system must not exceed 9 ohms. In this case, you can hope for a fast conversion process.
How to make a regulator for a soldering iron?
You can make a do-it-yourself current regulator for a soldering iron using a triode-type thyristor. Additionally, bipolar transistors and a low-pass filter are required. Capacitors in the device are used in an amount of no more than two units. The decrease in the anode current in this case should occur quickly. To solve the problem with negative polarity, switching converters are installed.
For sinusoidal voltage they are perfect. Directly control the current can be due to the rotary type regulator. However, push-button counterparts are also found in our time. To protect the device, the case is heat-resistant. Resonant transducers in models can also be found. They differ, in comparison with conventional counterparts, in their cheapness. On the market they can often be found with the marking PP200. The current conductivity in this case will be low, but the control electrode should cope with its duties.
Battery Chargers
To make a current regulator for a charger, thyristors are needed only triode type. The locking mechanism in this case will control the control electrode in the circuit. Field-effect transistors in devices are used quite often. The maximum load for them is 9 A. Low-pass filters for such regulators are not uniquely suitable. This is due to the fact that the amplitude of electromagnetic interference is quite high. This problem can be solved simply by using resonant filters. In this case, they will not interfere with the signal conductivity. Heat losses in the regulators should also be negligible.
Application of triac regulators
Triac controllers, as a rule, are used in devices whose power does not exceed 15 V. In this case, they can withstand the maximum voltage at 14 A. If we talk about lighting devices, then not all of them can be used. They are also not suitable for high voltage transformers. However, various radio equipment with them is able to work stably and without any problems.
Regulators for resistive load
The current regulator circuit for an active load of thyristors involves the use of a triode type. They are able to pass the signal in both directions. The decrease in the anode current in the circuit occurs due to a decrease in the limiting frequency of the device. On average, this parameter fluctuates around 5 Hz. The maximum output voltage should be 5 V. For this purpose, only field-type resistors are used. Additionally, ordinary capacitors are used, which on average are able to withstand a resistance of 9 ohms.
Pulse zener diodes in such regulators are not uncommon. This is due to the fact that the amplitude of electromagnetic oscillations is quite large and it is necessary to deal with it. Otherwise, the temperature of the transistors rises rapidly, and they become unusable. A variety of converters are used to solve the falling pulse problem. In this case, specialists can also use switches. They are installed in the regulators behind the field effect transistors. At the same time, they should not come into contact with capacitors.
How to make a phase controller model?
You can make a phase current regulator with your own hands using a thyristor marked KU202. In this case, the supply of blocking voltage will pass unhindered. Additionally, you should take care of the presence of capacitors with a limiting resistance of more than 8 ohms. The fee for this case can be taken by PP12. The control electrode in this case will provide good conductivity. Pulse converters in regulators of this type are quite rare. This is due to the fact that the average frequency level in the system exceeds 4 Hz.
As a result, a strong voltage is applied to the thyristor, which provokes an increase in negative resistance. To solve this problem, some suggest using push-pull converters. The principle of their operation is based on voltage inversion. It is rather difficult to make a current regulator of this type at home. As a rule, everything depends on finding the necessary converter.
Switching regulator device
To make a switching current regulator, a thyristor will need a triode type. The control voltage is supplied at high speed. Problems with reverse conductivity in the device are solved by bipolar type transistors. Capacitors in the system are installed only in pairs. The anode current in the circuit is reduced by changing the position of the thyristor.
Locking mechanism in regulators of this typeinstalled behind the resistors. A wide variety of filters can be used to stabilize the limiting frequency. Subsequently, the negative resistance in the regulator should not exceed 9 ohms. In this case, this will allow you to withstand a large current load.
Soft start models
In order to design a thyristor current regulator with a soft start, you need to take care of the modulator. Rotary analogs are considered to be the most popular today. However, they are quite different from each other. In this case, much depends on the board that is used in the device.
If we talk about modifications of the KU series, they work on the simplest regulators. They are not particularly reliable and still give certain failures. The situation is different with regulators for transformers. There, as a rule, digital modifications are applied. As a result, signal distortion is greatly reduced.
