Phase power regulator for inductive loads. Thyristor voltage regulator for transformer. Is it possible to make a regulator yourself

Transformers, like electric motors, have a steel core. In it, the upper and lower half-waves of the voltage must necessarily be symmetrical. This is what regulators are used for. Thyristors themselves are engaged in phase change. They can be used not only on transformers, but also on incandescent lamps, as well as on heaters.

If we consider the active voltage, then we need circuits that can handle a large load to carry out the inductive process. Some people use triacs in circuits, but they are not suitable for transformers with a power of more than 300 V. In this case, the problem is the spread of positive and negative polarities. Today, rectifier bridges can cope with a high resistive load. Thanks to them, the control pulse eventually reaches the holding current.

Diagram of a simple regulator

A simple regulator circuit includes a blocking-type thyristor directly and a controller for controlling the limit voltage. Transistors are used to stabilize the current at the beginning of the circuit. Capacitors are required before the controller. Some use combined analogues, but this is a controversial issue. In this case, the capacitance of the capacitors is estimated based on the power of the transformer. If we talk about negative polarity, then the inductors are installed only with the primary winding. The connection to the microcontroller in the circuit can be through an amplifier.

Is it possible to make a regulator yourself?

Do-it-yourself thyristor voltage regulator can be made by adhering to standard schemes. If we consider high-voltage modifications, then it is best to use sealed type resistors. They are able to withstand the limiting resistance at the level of 6 ohms. As a rule, vacuum analogues are more stable in operation, but their active parameters are underestimated. Resistors general purpose in this case it is better not to consider at all. On average, they withstand the nominal resistance only at the level of 2 ohms. As a result, the regulator will serious problems with current conversion.

For high power dissipation, PP201 class capacitors are used. They are distinguished by good accuracy, high-resistance wire is ideal for them. Lastly, a microcontroller with a circuit is selected. Low-frequency elements are not considered in this case. Single channel modulators should only be used in conjunction with amplifiers. They are installed at the first, as well as at the second resistors.

DC voltage devices

Thyristor regulators constant voltage well suited for impulse circuits. Capacitors in them, as a rule, are used only of the electrolytic type. However, they can be completely replaced by solid-state counterparts. Good current carrying capacity is provided by the rectifier bridge. Combined type resistors are used for high accuracy of the regulator. They are able to maintain maximum resistance at around 12 ohms. Only aluminum anodes can be present in the circuit. Their conductivity is quite good, the capacitor does not heat up very quickly.

The use of vacuum-type elements in devices is generally not justified. In this situation, thyristor DC voltage regulators will experience a significant reduction in frequency. To configure the device parameters, microcircuits of the CP1145 class are used. As a rule, they are designed for multi-channel and have at least four ports. There are six slots in total. The failure rate in such a circuit can be reduced by using fuses. They should only be connected to the power supply through a resistor.

AC voltage regulators

Thyristor AC voltage regulator output power on average, it has a level of 320 V. This is achieved due to the rapid flow of the inductance process. Rectifier bridges in the standard circuit are used quite rarely. Thyristors for regulators are usually taken four-electrode. They have only three outlets. Due to the high dynamic characteristics, they withstand the limiting resistance at the level of 13 ohms.

The maximum output voltage is 200 V. Due to the high heat transfer, amplifiers are absolutely not needed in the circuit. The thyristor is controlled by a microcontroller, which is connected to the board. Lockable transistors are installed in front of the capacitors. Also, high conductivity is provided by the anode circuit. The electrical signal in this case is quickly transmitted from the microcontroller to the rectifier bridge. Problems with negative polarity are solved by increasing the limiting frequency to 55 Hz. The optical signal is controlled by output electrodes.

Battery Charging Models

The thyristor battery charging voltage regulator (diagram shown below) is distinguished by its compactness. It is able to withstand the maximum resistance in the circuit at the level of 3 ohms. In this case, the current load can be only 4 A. All this indicates the weak characteristics of such regulators. Capacitors in the system are often used in a combined type.

Capacitance in many cases they do not exceed 60 pF. However, much in this situation depends on their series. Transistors in regulators use low-power ones. This is necessary so that the dispersion index is not so large. Ballistic transistors in this case are not suitable. This is due to the fact that they can only pass current in one direction. As a result, the voltage at the input and output will be very different.

Features of regulators for primary transformers

The thyristor voltage regulator for the primary transformer uses resistors of the emitter type. Due to this, the conductivity indicator is quite good. In general, such regulators are distinguished by their stability. The most common stabilizers are installed on them. IR22 class microcontrollers are used for power control. The current amplification factor in this case will be high. Transistors of the same polarity are not suitable for regulators of the specified type. Also, experts advise avoiding insulated gates for connecting elements. In this case, the dynamic characteristics of the controller will be significantly reduced. This is due to the fact that the output from the microcontroller will increase the negative resistance.

The regulator on the thyristor KU 202

The thyristor voltage regulator KU 202 is equipped with a two-channel microcontroller. It has three connectors in total. Diode bridges in the standard circuit are used quite rarely. In some cases, you can find various zener diodes. They are used solely to increase the maximum output power. They are also able to stabilize the operating frequency in regulators. Capacitors in such devices are more appropriate to use a combined type. As a result, the dissipation factor can be significantly reduced. You should also take into account throughput thyristors. Bipolar resistors are best suited for the output anode circuit.

Modification with thyristor KU 202N

The thyristor voltage regulator KU 202N is capable of transmitting a signal quite quickly. Thus, the current limit can be controlled at high speed. Heat transfer in this case will be low. The device should keep the maximum load at around 5 A. All this will allow you to easily cope with interference of various amplitudes. Also, do not forget about the nominal resistance at the input of the circuit. With the use of these thyristors in regulators, the induction process is carried out with the locking mechanisms turned off.

Scheme of the regulator KU 201l

Thyristor voltage regulator KU 201l includes bipolar transistors, as well as a multichannel microcontroller. Capacitors in the system are used only combined type. Electrolytic semiconductors in regulators are quite rare. Ultimately, this strongly affects the conductivity of the cathode.

Solid state resistors are needed only to stabilize the current at the beginning of the circuit. Resistors with dielectrics can be used in pair with rectifier bridges. In general, these thyristors are capable of boasting high accuracy. However, they are quite sensitive and keep the operating temperature low. Due to this, the failure rate can be fatal.

Regulator with thyristor KU 201a

Capacitors are provided by a thyristor voltage regulator of a tuning type. Their nominal capacitance is at the level of 5 pF. In turn, they withstand the ultimate resistance of exactly 30 ohms. High current conductivity is provided due to the interesting construction of transistors. They are located on both sides of the power source. It is important to note that current flows through the resistors in all directions. The microcontroller of the PPR233 series is presented as a closing mechanism. Periodic adjustment of the system can be done with it.

Parameters of the device with thyristor KU 101g

These thyristor voltage regulators are used for connection to high-voltage transformers. Their schemes involve the use of capacitors with a limiting capacitance of 50 pF. Interlinear counterparts are not able to boast of such indicators. Rectifier bridges play an important role in the system.

Bipolar transistors can additionally be used to stabilize the voltage. Microcontrollers in devices must withstand the limiting resistance at the level of 30 ohms. The actual induction process proceeds quite quickly. It is permissible to use amplifiers in regulators. In many ways, this will help to increase the conductivity threshold. The sensitivity of such regulators leaves much to be desired. The limiting temperature of thyristors reaches 40 degrees. Because of this, they need fans to cool the system.

Properties of the regulator with thyristor KU 104a

With transformers whose power exceeds 400 V, these thyristor voltage regulators work. The layout of the main elements they may vary. In this case, the limiting frequency should be at the level of 60 Hz. All this ultimately puts a huge load on the transistors. Here they are used closed.

Due to this, the performance of such devices is significantly improved. At the output, the operating voltage is on average at the level of 250 V. It is not advisable to use ceramic capacitors in this case. Also, a big question for experts is the use of tuning mechanisms to adjust the current level.

A selection of circuits and a description of the operation of the power regulator on triacs and not only. Triac power control circuits are well suited for extending the life of incandescent lamps and for adjusting their brightness. Or for powering non-standard equipment, for example, at 110 volts.

The figure shows a diagram of a triac power controller, which can be changed by changing total network half-cycles skipped by the triac for a certain time interval. On the elements of the DD1.1.DD1.3 chip, the oscillation period of which is about 15-25 network half-cycles.

The duty cycle of the pulses is regulated by the resistor R3. Transistor VT1, together with diodes VD5-VD8, is designed to bind the moment the triac is turned on during the transition of the mains voltage through zero. Basically, this transistor is open, respectively, "1" is supplied to the input DD1.4 and the transistor VT2 with the triac VS1 is closed. At the moment of zero crossing, transistor VT1 closes and opens almost immediately. In this case, if the output of DD1.3 was 1, then the state of the elements DD1.1.DD1.6 will not change, and if the output of DD1.3 was "zero", then the elements DD1.4.DD1.6 will generate a short pulse, which will be amplified by the transistor VT2 and open the triac.

As long as the generator output is a logical zero, the process will go cyclically after each transition of the mains voltage through the zero point.

The basis of the circuit is a foreign triac mac97a8, which allows you to switch high power connected loads, and used an old Soviet variable resistor to adjust it, and used a regular LED as an indication.

The triac power controller uses the principle of phase control. The operation of the power regulator circuit is based on a change in the moment the triac is turned on relative to the transition of the mains voltage through zero. At the initial moment of the positive half-cycle, the triac is in the closed state. With increasing mains voltage, capacitor C1 is charged through the divider.

The increasing voltage on the capacitor is phase shifted from the mains by an amount depending on the total resistance of both resistors and the capacitance of the capacitor. The capacitor is charged until the voltage across it reaches the “breakdown” level of the dinistor, approximately 32 V.

At the moment the dinistor is opened, the triac will also open, a current will flow through the load connected to the output, depending on the total resistance of the open triac and the load. The triac will be open until the end of the half cycle. Resistor VR1 sets the opening voltage of the dinistor and triac, thereby adjusting the power. At the moment of action of the negative half-cycle, the algorithm of the circuit is similar.

Circuit variant with minor modifications for 3.5 kW

The regulator circuit is simple, the load power at the output of the device is 3.5 kW. With this DIY ham radio you can control lights, heating elements and more. The only one significant disadvantage of this circuit, this is that it is impossible to connect an inductive load to it in any case, because the triac will burn out!

Radio components used in the design: Triac T1 - BTB16-600BW or similar (KU 208 il VTA, VT). Dinistor T - type DB3 or DB4. Capacitor 0.1uF ceramic.

Resistance R2 510 ohm limits the maximum volts on the capacitor to 0.1 uF, if you put the regulator slider in the 0 ohm position, then the circuit resistance will be about 510 ohms. The capacitance is charged through resistors R2 510Ω and variable resistance R1 420kΩ, after U on the capacitor reaches the opening level of the DB3 dinistor, the latter will generate a pulse that unlocks the triac, after which, with a further passage of the sinusoid, the triac is locked. The opening-closing frequency T1 depends on the level U on the 0.1 μF capacitor, which depends on the resistance of the variable resistor. That is, by interrupting the current (at a high frequency) the circuit thereby regulates the output power.

With each positive half-wave of the input AC voltage, capacitance C1 is charged through a chain of resistors R3, R4, when the voltage across capacitor C1 becomes equal to the opening voltage of the dinistor VD7, it will breakdown and discharge the capacitance through the diode bridge VD1-VD4, as well as resistance R1 and control electrode VS1. To open the triac, an electrical circuit of diodes VD5, VD6 of capacitor C2 and resistance R5 is used.

It is required to select the value of the resistor R2 so that at both half-waves of the mains voltage, the triac of the regulator operates reliably, and it is also required to select the values ​​of the resistances R3 and R4 so that when the variable resistance knob R4 is rotated, the voltage at the load changes smoothly from minimum to maximum values. Instead of the triac TS 2-80, you can use TS2-50 or TS2-25, although there will be a slight loss in allowable power in the load.

KU208G, TS106-10-4, TS 112-10-4 and their analogues were used as a triac. At that moment in time when the triac is closed, the capacitor C1 is charged through the connected load and resistors R1 and R2. The charge rate is changed by resistor R2, resistor R1 is designed to limit the maximum charge current

When the threshold voltage on the capacitor plates is reached, the key opens, the capacitor C1 quickly discharges to the control electrode and switches the triac from the closed state to the open state, in the open state the triac shunts the circuit R1, R2, C1. At the moment the mains voltage passes through zero, the triac closes, then the capacitor C1 is charged again, but with a negative voltage.

Capacitor C1 from 0.1 ... 1.0 uF. Resistor R2 1.0 ... 0.1 MΩ. The triac is turned on by a positive current pulse to the control electrode at a positive voltage at the conditional anode output and a negative current pulse to the control electrode at a negative voltage of the conditional cathode. So the key element for the regulator is to be bidirectional. You can use a bidirectional dinistor as a key.

Diodes D5-D6 are used to protect the thyristor from possible reverse voltage breakdown. The transistor operates in the avalanche breakdown mode. Its breakdown voltage is about 18-25 volts. If you do not find P416B, then you can try to find a replacement for it.

The pulse transformer is wound on a ferrite ring with a diameter of 15 mm, grade H2000. The thyristor can be replaced with KU201

The circuit of this power regulator is similar to the circuits described above, only an interference suppression circuit C2, R3 is introduced, and the switch SW makes it possible to break the charging circuit of the control capacitor, which leads to instant blocking of the triac and disconnection of the load.

C1, C2 - 0.1 uF, R1-4k7, R2-2 mOhm, R3-220 Ohm, VR1-500 kOhm, DB3 - dinistor, BTA26-600B - triac, 1N4148/16 V - diode, any LED.

The regulator is used to adjust the load power in circuits up to 2000 W, incandescent lamps, heating appliances, soldering iron, asynchronous motors, charger for cars, and if you replace the triac with a more powerful one, you can use it in the current regulation circuit in welding transformers.

The principle of operation of this power regulator circuit is that the load receives a half-cycle of mains voltage after a selected number of missed half-cycles.

diode bridge rectify AC voltage. Resistor R1 and zener diode VD2, together with the filter capacitor, form a 10 V power supply for powering the K561IE8 chip and the KT315 transistor. The rectified positive voltage half-cycles passing through the capacitor C1 are stabilized by the zener diode VD3 at a level of 10 V. Thus, pulses with a frequency of 100 Hz follow the counting input C of the K561IE8 counter. If switch SA1 is connected to output 2, then the transistor base will always have a logic-one level. Because the reset pulse of the microcircuit is very short and the counter has time to restart from the same pulse.

Pin 3 will be set to logic 1. The thyristor will be open. All power will be allocated to the load. In all subsequent positions of SA1 at pin 3 of the counter, one pulse will pass through 2-9 pulses.

The K561IE8 chip is a decimal counter with a positional decoder at the output, so the logical unit level will be periodically at all outputs. However, if the switch is set to output 5 (pin 1), then the count will only occur up to 5. When the pulse passes output 5, the microcircuit will be reset. The count will start from zero, and a logical one level will appear at pin 3 for the duration of one half-cycle. At this time, the transistor and thyristor open, one half-cycle passes into the load. In order to make it clearer, I give vector diagrams of the operation of the circuit.

If you want to reduce the load power, you can add another counter chip by connecting pin 12 of the previous chip to pin 14 of the next. By installing another switch, it will be possible to adjust the power up to 99 missed pulses. Those. you can get about a hundredth of the total power.

The KR1182PM1 microcircuit has two thyristors and a control unit for them in its internal composition. The maximum input voltage of the KR1182PM1 chip is about 270 volts, and the maximum load can reach 150 watts without using an external triac and up to 2000 watts using, and also taking into account that the triac will be installed on a radiator.

To reduce the level of external interference, capacitor C1 and inductor L1 are used, and capacitance C4 is required to smoothly turn on the load. Adjustment is carried out using the resistance R3.

Compilation Pretty simple circuits regulators for a soldering iron will simplify the life of a radio amateur

Combination is the combination of ease of use digital controller and the flexibility of easy adjustment.

The considered power regulator circuit works on the principle of changing the number of periods of the input alternating voltage going to the load. This means that the device cannot be used to adjust the brightness of incandescent lamps due to the blinking visible to the eye. The circuit makes it possible to adjust the power within eight preset values.

There are a huge number of classic thyristor and triac controller circuits, but this controller is made on a modern element base and, moreover, was a phase one, i.e. it does not pass the entire half-wave of the mains voltage, but only some of it, thereby limiting the power, because the opening of the triac occurs only at the desired phase angle.

POWER REGULATION

Most often, power regulators of devices are made on trinistors, using it as a powerful output key. But the trinistor in the AC circuit is inconvenient in that it requires power through a rectifier bridge, which, with a high load power, must be installed on a radiator. In this regard, a triac is more convenient for a key element. The main difference is the possibility of switching not only direct, but also alternating current, which can flow in any direction - both from the anode to the cathode, and in the opposite direction.

For reference: triacs with a positive voltage at the anode can be switched on by pulses of any polarity applied to the control electrode relative to the cathode, and with a negative voltage at the anode - by pulses of only negative polarity. Triac control direct current requires a lot of power, and pulse control requires a shaper that provides short pulses at the time the mains voltage passes through zero, which reduces the level of interference compared to regulators that use the phase-pulse control method.

The power control device contains a triac, a time (phase) delay unit, a compensating circuit and a power source. Compensating circuit R8 C2 to the voltage of the zener diode VD3 adds a voltage value proportional to the supply voltage. This amount is the interbase voltage of the unijunction transistor KT117. Reducing the supply voltage reduces the supply voltage of the transistor and causes a decrease in the time delay. From the well-known circuit of a triac power regulator on the BT136-600 and the DB-3 dinistor, this one differs in the stabilization of control pulses and, accordingly, greater accuracy and invariability of the output voltage.

When setting up a power control device, it is necessary to connect it to the network with a load through, and install a voltmeter in parallel with the load. By changing the voltage with a variable resistor R8 at the input of the regulator, we achieve the minimum voltage at the load. The transformer is made on a Sh5x6 core, the primary winding is 40 turns, the secondary is 50 turns PEL-0.2 - 0.3. In my version of the power control device, I installed a transformer on a K20x10x6 ferrite ring with two identical windings of 40 turns each - everything worked fine. For visual control of the voltage (power) at the load, I installed a small AC voltmeter assembled from the recording level indicator of a reel-to-reel Soviet tape recorder. We connect it naturally in parallel with the load. red glow indicates that the power control device is connected to the network and the scale is illuminated.

An active load with a power of up to two kilowatts can be connected to this regulator - electric stoves, electric kettles, electric fireplaces, irons, etc., and when replacing the triac with a more powerful one, for example TS132-50, up to 10 kW. A real use case: a neighbor is constantly knocking out plugs with 16 A automatic machines when operating an electric kettle Tefal 2 kW. Replacing them is impossible, since he does not live in his apartment. The problem was solved by this adjustment device, set at 80% power.

Useful improvements: when working with an inductive load, an RC circuit must be connected in parallel with the triac of the power regulator to limit the rate of rise of the anode voltage. Any triac regulator is a source of radio interference, so it is desirable to equip the power regulator with a radio interference filter. The LC radio noise filter is a conventional G-filter with a coil and a capacitor. As a choke L, a coil of 100 turns of wire wound on a ferrite rod with a diameter of 8 mm and a length of 50 mm is used. A wire diameter of 1 mm corresponds to a maximum load power of approximately 700 W. The fuse for the rated load current protects the triac from short circuit in load. When setting up, observe safety measures, since all elements of the power control device are galvanically connected to a 220 V network.

Questions and comments on the scheme - on

To control some types of household appliances (for example, a power tool or a vacuum cleaner), a triac-based power regulator is used. You can learn more about the principle of operation of this semiconductor element from the materials posted on our website. In this publication, we will consider a number of issues related to triac load power control circuits. As always, let's start with theory.

The principle of operation of the regulator on the triac

Recall that it is customary to call a triac a modification of a thyristor, which plays the role of a semiconductor switch with a non-linear characteristic. Its main difference from the basic device lies in the two-way conduction during the transition to the "open" mode of operation, when current is applied to the control electrode. Due to this property, triacs do not depend on the polarity of the voltage, which allows them to be effectively used in circuits with alternating voltage.

In addition to the acquired feature, these devices have an important property of the base element - the ability to maintain conductivity when the control electrode is turned off. In this case, the "closing" of the semiconductor key occurs at the moment of the absence of a potential difference between the main terminals of the device. That is, when the alternating voltage passes the zero point.

An additional bonus from such a transition to the "closed" state is the reduction in the number of interference in this phase of operation. Note that a non-interference regulator can be built to be driven by transistors.

Due to the properties listed above, it is possible to control the load power by phase control. That is, the triac opens every half cycle and closes when passing through zero. The delay time for turning on the "open" mode, as it were, cuts off part of the half-cycle, as a result, the shape of the output signal will be sawtooth.

In this case, the signal amplitude will remain the same, which is why such devices are incorrectly called voltage regulators.

Regulator circuit options

Here are some examples of circuits that allow you to control the load power using a triac, let's start with the simplest one.

Designations:

• Resistors: R1 - 470 kOhm, R2 - 10 kOhm,
• Capacitor C1 - 0.1 uF x 400 V.
• Diodes: D1 - 1N4007, D2 - any indicator LED 2.10-2.40V 20mA.
• Dinistor DN1 - DB3.
• Triac DN2 - KU208G, you can install more powerful analogue BTA16 600.

With the help of the DN1 dinistor, the D1-C1-DN1 circuit is closed, which puts DN2 in the “open” position, in which it remains until the zero point (the end of the half-cycle). The moment of opening is determined by the accumulation time on the capacitor of the threshold charge required to switch DN1 and DN2. The charge rate of C1 is controlled by the R1-R2 chain, the total resistance of which determines the moment of “opening” of the triac. Accordingly, the load power is controlled by means of a variable resistor R1.

Despite the simplicity of the circuit, it is quite effective and can be used as a dimmer for filament lighting fixtures or a soldering iron power regulator.

Unfortunately, this diagram does not feedback therefore, it is not suitable as a stabilized speed controller for a commutator motor.

Feedback Regulator Circuit

Feedback is necessary to stabilize the speed of the electric motor, which can change under the influence of the load. You can do this in two ways:

1. Install a tachometer that measures the number of revolutions. This option allows for fine adjustment, but it increases the cost of implementing the solution.
2. Track voltage changes on the electric motor and, depending on this, increase or decrease the “open” mode of the semiconductor switch.

The latter option is much easier to implement, but requires a little adjustment to the power of the electric machine used. Below is a diagram of such a device.

Designations:

• Resistors: R1 - 18 kOhm (2 W); R2 - 330 kOhm; R3 - 180 Ohm; R4 and R5 - 3.3 kOhm; R6 - it is necessary to select how this is done will be described below; R7 - 7.5 kOhm; R8 - 220 kOhm; R9 - 47 kOhm; R10 - 100 kOhm; R11 - 180 kOhm; R12 - 100 kOhm; R13 - 22 kOhm.
• Capacitors: C1 - 22 uF x 50 V; C2 - 15 nF; C3 - 4.7 uF x 50 V; C4 - 150 nF; C5 - 100 nF; C6 - 1 uF x 50 V ..
• Diodes D1 - 1N4007; D2 - any indicator LED for 20 mA.
• Triac T1 - BTA24-800.
• Chip - U2010B.

This scheme provides a smooth start of the electrical installation and provides its protection against overload. Three operating modes are allowed (set by switch S1):

• A - When overloaded, LED D2 turns on, signaling an overload, after which the engine reduces speed to the minimum. To exit the mode, you must turn off and turn on the device.
• B - In case of overload, LED D2 turns on, the motor is switched to work with a minimum speed. To exit the mode, it is necessary to remove the load from the electric motor.
• C - Overload indication mode.

Setting up the circuit is reduced to the selection of resistance R6, it is calculated, depending on the power, of the electric motor according to following formula: . For example, if we need to drive a 1500 W motor, then the calculation will be as follows: 0.25 / (1500 / 240) = 0.04 ohms.

For the manufacture of this resistance, it is best to use a nichrome wire with a diameter of 0.80 or 1.0 mm. Below is a table that allows you to select the resistance R6 and R11, depending on the engine power.

This device can be used as a speed controller for motors of power tools, vacuum cleaners and other household equipment.

Regulator for inductive load

Those who try to drive an inductive load (such as a transformer welding machine) using the above schemes, disappointment awaits. The devices will not work, and the failure of the triacs is quite possible. This is due to the phase shift, which is why the semiconductor key does not have time to switch to the “open” mode during a short pulse.

There are two options for solving the problem:

1. Submission to the control electrode of a series of pulses of the same type.
2. Apply a constant signal to the control electrode until it passes through zero.

The first option is the most optimal. Here is a diagram where such a solution is used.

As can be seen from the following figure, which shows the oscillograms of the main signals of the power regulator, a burst of pulses is used to open the triac.

This device makes it possible to use semiconductor switch regulators to control an inductive load.

A simple do-it-yourself power regulator on a triac

At the end of the article, we give an example of a simple power regulator. In principle, any of the above schemes can be assembled (the most simplified version was shown in Figure 2). For this device, it is not even necessary to do printed circuit board, the device can be assembled by surface mounting. An example of such an implementation is shown in the figure below.

You can use this regulator as a dimmer, as well as control powerful electric heating devices with it. We recommend choosing a circuit in which a semiconductor switch is used for control with characteristics corresponding to the load current.

Recently, resistor and transistor power controllers have experienced a real renaissance. They are the most economical. You can increase the efficiency of the regulator in the same way as the regulator by turning on the diode (see figure). This achieves a more convenient control limit (50-100%). Semiconductor devices can be placed on a single heatsink. Yu.I.Borodaty, Ivano-Frankivsk region Literature 1. Danilchuk A.A. Regulator power for a soldering iron / /Radioamator-Electric. -2000. -#9. -p.23. 2. Rishtun A Regulator tightness on six details // Radioamator-Electrician. -2000. -#11. -S.15....

For the circuit "POWER REGULATOR WITH FEEDBACK"

The load of this simple regulator can include incandescent lamps, heating devices various types and so on, according to the applied thyristors. The method for setting the regulator is contained in the selection of a variable control resistor. However, it is best to choose such a potentiometer, in series with a constant resistor, so that the voltage at the output of the regulator varies as widely as possible. A.ANDRIENKO, Kostroma....

For the scheme "SIMPLE TEMPERATURE CONTROL OF THE SOLDERING TIP"

Consumer Electronics 3. This circuit is not my own design. I saw her for the first time in Radio magazine. I think it will interest many radio amateurs with its simplicity. The device allows you to adjust the power of the soldering iron from half to maximum. With the elements indicated in the diagram, the power loads should not exceed 50 W, but within an hour the circuit can transfer a load of 100 W without any special consequences. The regulator circuit is shown in the figure. If the VD2 thyristor is replaced by KU201, and the VD1 diode by KD203V, the connected power can be significantly increased. The output power is minimal in the extreme left (according to the diagram) position of the R2 engine. In my version, it is mounted in a table lamp stand using the hinged mounting method. At the same time, one network outlet is saved, which, as you know, is always in short supply. This one has been working for me for 14 years without any complaints. Literature 1. Radio, 1975, N6, C.53....

For the scheme "Simple power regulator"

The inductive load in the regulator circuit imposes strict requirements on the triac management circuits - the synchronization of the management system must be carried out directly from the mains, the signal must have a duration equal to the triac conduction interval. The figure shows a diagram of a regulator that meets these requirements, which uses a combination of a dinistor and a triac. The time constant (R4 + R5) C3 determines the angle of delay in unlocking the dinistor VS1 and hence the triac VS2. Moving the slider of the variable resistor R5 regulates the power consumed by the load. Capacitor C2 and resistor R2 are used to synchronize and maintain the duration of the management signal. Capacitor C3 is recharged from C2 after switching, since at the end of each half-cycle it has a reverse polarity voltage. To protect against interference created by the regulator, two Filters R1C1 are introduced - into the power circuit and R7C4 - into the load circuit. To establish the device, you need to set the resistor R5 to the position of maximum resistance and set the minimum power to the load with resistor R3 Capacitors C1 and C4 of the K40P-2B type for 400 V Capacitors C2 and SZ of the K73-17 type for 250 V Diode bridge VD1 can be replaced by diodes KD105B Switch SA1 designed for a current of at least 5 A. VF Yakovlev, Shostka, Sumy region. ...

For the circuit "Triac power controller"

The proposed device (Fig. 1) is a phase power capable of operating with a load from several watts to units of kilowatts. This design is a reworking of a previously developed device. The use of a different element base made it possible to simplify the power unit of the structure, increase reliability and improve the operational characteristics of the regulator. As in the prototype, this regulator has a smooth and stepwise adjustment of the power supplied to the load. In addition, at any time (without touching the regulator knobs), the device can be switched to the operating mode when almost 100% of the power is supplied to the load. There is virtually no radio interference. The power switch is built on a powerful triac VS2. The minimum power connected can be from 3 to 10 watts. maximum (1.5 kW) is limited by the type of triac used, the conditions for its cooling and the design of noise suppression chokes. Structural diagram of the microcircuit 251 1HT On low-power transistors VT3. VT4 is an analogue of a unijunction transistor, which reinforces short pulses that open a low-power high-voltage thyristor VS1. The power supplied to the load depends on the resistance of the variable resistor R6. The opened low-power thyristor, in turn, opens a powerful triac VS2. Through the opened triac, the supply voltage is supplied to the load. In order to have a chance, for example, it is time to reduce the brightness of the lamp or the temperature of the soldering iron. and then return to the previous set value, a stepped power management node is built on the DD1 chip. The first time you press the SB1 button, the DD1.2 trigger switches, a large logic voltage level ("G") appears at output 1 DD1.2, the transistor VT2 opens and shunts the amplitude limiting circuit of the mains voltage VD2-HL2. Power ...

Power supply "SOFT" LOAD IN THE MAINS MAINS When connecting and disconnecting loads interference often occurs in the electrical network, which disrupts the normal operation of sensitive electronic devices and electrical systems. The device, the scheme of which is shown in Fig. 1, realizes "soft" connection and disconnection of the load. \u003d SOFT LOAD IN THE ELECTRICAL NETWORKPuc.1 When the contacts of the switch SA1 are closed during the charging of the capacitor C1 (through the resistor R1), the transistor VT1 gradually opens and the collector current gradually increases to a value determined by the ratio of the resistances of the resistors R1 and R2. Accordingly, the current in the load also gradually increases. When turned off, the capacitor discharges through resistor R2 and the base-emitter junction of the transistor. The current gradually decreases to zero. With the values ​​\u200b\u200bof the elements and 200 W indicated on the diagram, the duration of the on-time process is 0.1 s, off - 0.5 s. How to check the k174ps1 microcircuit The voltage losses in this device are relatively small, they are determined by the sum of the forward drop on two diodes and the collector-emitter section of a working transistor, which is approximately: Uce (B) \u003d 0.7 + R1 * In / h21e Depending on the current loads and the current transfer coefficient of the base of the transistor, resistor R should be selected in such a way that the voltage drop across the transistor and the power dissipation on it would be maintained in the on state for acceptable level. =SOFT LOAD IN THE POWER MAINSPuc.2 In the device variant shown in fig. 2, armor is provided ...

For the circuit "SOFT IGNITION OF THE INCANDESCENT LAMP"

Consumer electronicsSOFT IGNITION OF THE INCANDESCENT LAMP The device provides protection of the lighting lamp from current surges at the moment of switching on and smooth heating of its filament, as well as adjustment of the maximum power loads. Its advantage over some similar ones, for example, published in - simplicity, combined with a fairly high reliability. The basis (see diagram) is the method of phase-pulse management of the trinistor, described in [3]. The principle of operation of such a device is well known to readers of "Radio", and therefore we will consider in detail only the work of the still introduced automatic load power management circuit, consisting of a diode VD4, capacitor C1 and resistors R2, R3. Immediately after being connected to the network, capacitor C1 begins to be charged by current pulses flowing through resistor R2, diode VD4 and resistor R3. The peak role of the voltage at point A is still not enough to open the unijunction transistor VT1, so it is closed, and, of course, the trinistor VS1 is also closed. At this hour, no current flows through the load EL1. T160 current regulator circuit As the capacitor C1 charges, the role of the impulse voltage at point A increases. When it reaches the transistor opening threshold, capacitor C1 begins to discharge through its emitter-base junction, as a result of which short pulses opening it are sent to the control electrode of the trinistor. The power dissipated in the load is determined by the phase shift between the control pulse and the beginning of the SCR anode voltage period, as well as the control pulse repetition rate, since at the beginning of the process one pulse is formed over several periods of the mains voltage. These two parameters that determine the operation of the trinistor depend on the charging rate of the capacitor C2, i.e., on the peak voltage at point A and the resistance of the input part of the variable resistor R4. As the capacitor C1 charges (after 1 ... 2 s), the average current flowing through the VD4 diode decreases ...

For the scheme "VOLTAGE CONVERTER PN-32"

Power supply VOLTAGE CONVERTER PN-32(S) RINTELsay Oleg, (RA3XBJ). The converter is designed to power equipment with a rated voltage of 12 V (SV radio stations, radio tape recorders, TVs, etc.) from the on-board network of cars with a voltage of 24 V. Maximum current loads converter up to 3A for a short time and 2-2.5 A for a long time (determined by the area of ​​\u200b\u200bthe radiator of the output transistor). Efficiency 75-90% depending on the load current. The converter circuit does not contain scarce parts. The inductor is wound on a ferrite ring with a diameter of 32 mm and has 50 turns of PETV-0.63 wire. Converter dimensions 65x90x40 mm. Questions on the design can be asked to the author [email protected]...