Powerful 12V PWM speed controller with your own hands. Speed ​​controller for commutator motor: device and do-it-yourself manufacturing

On simple mechanisms it is convenient to install analog current regulators. For example, they can change the speed of rotation of the motor shaft. From the technical side, implementing such a regulator is simple (you will need to install one transistor). Suitable for adjusting independent speed of motors in robotics and power supplies. The most common types of regulators are single-channel and two-channel.

Video No. 1. Single-channel regulator in operation. Changes the rotation speed of the motor shaft by rotating the variable resistor knob.

Video No. 2.

Increasing the rotation speed of the motor shaft when operating a single-channel regulator. An increase in the number of revolutions from the minimum to the maximum value when rotating the variable resistor knob. Video No. 3.

Two-channel regulator in operation. Independent setting of the torsion speed of motor shafts based on trimming resistors.

Video No. 4.

The voltage at the output of the regulator was measured with a digital multimeter. The resulting value is equal to the battery voltage, from which 0.6 volts have been subtracted (the difference arises due to the voltage drop across the transistor junction). When using a 9.55 volt battery, a change from 0 to 8.9 volts is recorded.

Functions and main characteristics

The load current of single-channel (photo 1) and two-channel (photo 2) regulators does not exceed 1.5 A. Therefore, to increase the load capacity, the KT815A transistor is replaced with KT972A. The numbering of the pins for these transistors is the same (e-k-b). But the KT972A model is operational with currents up to 4A.

  1. Single channel motor controller

The device controls one motor, powered by voltage in the range from 2 to 12 volts.

Device design The main design elements of the regulator are shown in the photo. 3. The device consists of five components: two variable resistance resistors with a resistance of 10 kOhm (No. 1) and 1 kOhm (No. 2), a transistor model KT815A (No. 3), a pair of two-section screw terminal blocks for the output for connecting a motor (No. 4) and input for connecting a battery (No. 5).

  1. Note 1.

The operating procedure of the motor controller is described in the electrical diagram (Fig. 1). Taking into account the polarity, a constant voltage is supplied to the XT1 connector. The light bulb or motor is connected to the XT2 connector. A variable resistor R1 is turned on at the input; rotating its knob changes the potential at the middle output as opposed to the minus of the battery. Through current limiter R2, the middle output is connected to the base terminal of transistor VT1. In this case, the transistor is switched on according to a regular current circuit. The positive potential at the base output increases as the middle output moves upward from the smooth rotation of the variable resistor knob. There is an increase in current, which is due to a decrease in the resistance of the collector-emitter junction in transistor VT1. The potential will decrease if the situation is reversed.


Electrical circuit diagram
  1. Materials and details

A printed circuit board measuring 20x30 mm is required, made of a fiberglass sheet foiled on one side (permissible thickness 1-1.5 mm). Table 1 provides a list of radio components.

Note 2. The variable resistor required for the device can be of any manufacture; it is important to observe the current resistance values ​​​​for it indicated in Table 1.

Note 3. To regulate currents above 1.5A, the KT815G transistor is replaced with a more powerful KT972A (with a maximum current of 4A). In this case, the printed circuit board design does not need to be changed, since the distribution of pins for both transistors is identical.

  1. Build process

For further work, you need to download the archive file located at the end of the article, unzip it and print it. The regulator drawing (file) is printed on glossy paper, and the installation drawing (file) is printed on a white office sheet (A4 format).

Next, the drawing of the circuit board (No. 1 in photo. 4) is glued to the current-carrying tracks on the opposite side of the printed circuit board (No. 2 in photo. 4). It is necessary to make holes (No. 3 in photo. 14) on the installation drawing in the mounting locations. The installation drawing is attached to the printed circuit board with dry glue, and the holes must match. Photo 5 shows the pinout of the KT815 transistor.

The input and output of terminal blocks-connectors are marked in white. A voltage source is connected to the terminal block via a clip. A fully assembled single-channel regulator is shown in the photo. The power source (9 volt battery) is connected at the final stage of assembly. Now you can adjust the shaft rotation speed using the motor; to do this, you need to smoothly rotate the variable resistor adjustment knob.

To test the device, you need to print a disk drawing from the archive. Next, you need to paste this drawing (No. 1) onto thick and thin cardboard paper (No. 2). Then, using scissors, a disc is cut out (No. 3).

The resulting workpiece is turned over (No. 1) and a square of black electrical tape (No. 2) is attached to the center for better adhesion of the surface of the motor shaft to the disk. You need to make a hole (No. 3) as shown in the image. Then the disk is installed on the motor shaft and testing can begin. The single-channel motor controller is ready!

Two-channel motor controller

Used to independently control a pair of motors simultaneously. Power is supplied from a voltage ranging from 2 to 12 volts. The load current is rated up to 1.5A per channel.

  1. Single channel motor controller

The main components of the design are shown in photo.10 and include: two trimming resistors for adjusting the 2nd channel (No. 1) and the 1st channel (No. 2), three two-section screw terminal blocks for output to the 2nd motor (No. 3), for output to the 1st motor (No. 4) and for input (No. 5).

Note:1 Installation of screw terminal blocks is optional. Using a thin stranded mounting wire, you can connect the motor and power source directly.

  1. Note 1.

The circuit of a two-channel regulator is identical to the electrical circuit of a single-channel regulator. Consists of two parts (Fig. 2). The main difference: the variable resistance resistor is replaced with a trimming resistor. The rotation speed of the shafts is set in advance.

Note.2.

  1. Materials and details

To quickly adjust the rotation speed of the motors, the trimming resistors are replaced using a mounting wire with variable resistance resistors with the resistance values ​​indicated in the diagram.

  1. Build process

You will need a printed circuit board measuring 30x30 mm, made of a fiberglass sheet foiled on one side with a thickness of 1-1.5 mm. Table 2 provides a list of radio components.

After downloading the archive file located at the end of the article, you need to unzip it and print it. The regulator drawing for thermal transfer (termo2 file) is printed on glossy paper, and the installation drawing (montag2 file) is printed on a white office sheet (A4 format).

Any of the inputs is connected to the pole of the power source (a 9-volt battery is shown in the example). The negative of the power supply is attached to the center of the terminal block. It is important to remember: the black wire is “-” and the red wire is “+”.

The motors must be connected to two terminal blocks, and the desired speed must also be set. After successful testing, you need to remove the temporary connection of the inputs and install the device on the robot model. The two-channel motor controller is ready!

The necessary diagrams and drawings for the work are presented. The emitters of the transistors are marked with red arrows.

The DC motor speed controller circuit operates on the principles of pulse width modulation and is used to change the speed of a 12 volt DC motor. Regulating the engine shaft speed using pulse-width modulation gives greater efficiency than simply changing the DC voltage supplied to the engine, although we will also consider these schemes

DC motor speed controller circuit for 12 volts

The motor is connected in a circuit to a field-effect transistor which is controlled by pulse-width modulation carried out on the NE555 timer chip, which is why the circuit turned out to be so simple.

The PWM controller is implemented using a conventional pulse generator on an astable multivibrator, generating pulses with a repetition rate of 50 Hz and built on the popular NE555 timer. The signals coming from the multivibrator create a bias field at the gate of the field-effect transistor. The duration of the positive pulse is adjusted using variable resistance R2. The longer the duration of the positive pulse arriving at the gate of the field-effect transistor, the greater the power supplied to the DC motor. And vice versa, the shorter the pulse duration, the weaker the electric motor rotates. This circuit works great on a 12 volt battery.

DC motor speed control circuit for 6 volts

The speed of the 6 volt motor can be adjusted within 5-95%

Engine speed controller on PIC controller

Speed ​​control in this circuit is achieved by applying voltage pulses of varying duration to the electric motor. For these purposes, PWM (pulse width modulators) are used. In this case, pulse width control is provided by a PIC microcontroller. To control the engine rotation speed, two buttons SB1 and SB2, “More” and “Less,” are used. You can change the rotation speed only when the “Start” toggle switch is pressed. The pulse duration varies, as a percentage of the period, from 30 to 100%.

As a voltage stabilizer for the PIC16F628A microcontroller, a three-pin KR1158EN5V stabilizer is used, which has a low input-output voltage drop, only about 0.6V. The maximum input voltage is 30V. All this allows the use of motors with voltages from 6V to 27V. The KT829A composite transistor is used as a power switch, which is preferably installed on a radiator.

The device is assembled on a printed circuit board measuring 61 x 52 mm. You can download the PCB drawing and firmware file from the link above. (See folder in the archive 027-el)

PWM DC motor speed controller

This DIY circuit can be used as a speed controller for a 12V DC motor with a current rating of up to 5A, or as a dimmer for 12V halogen and LED lamps up to 50W. Control is carried out using pulse width modulation (PWM) at a pulse repetition rate of about 200 Hz. Naturally, the frequency can be changed if necessary, selecting for maximum stability and efficiency.

Most of these structures are assembled according to a much simpler scheme. Here we present a more advanced version that uses a 7555 timer, a bipolar transistor driver and a powerful MOSFET. This design provides improved speed control and operates over a wide load range. This is indeed a very effective scheme and the cost of its parts when purchased for self-assembly is quite low.

PWM controller circuit for 12 V motor

The circuit uses a 7555 Timer to create a variable pulse width of about 200 Hz. It controls transistor Q3 (via transistors Q1 - Q2), which controls the speed of the electric motor or light bulbs.

There are many applications for this circuit that will be powered by 12V: electric motors, fans or lamps. It can be used in cars, boats and electric vehicles, in model railways and so on.

12 V LED lamps, for example LED strips, can also be safely connected here. Everyone knows that LED bulbs are much more efficient than halogen or incandescent bulbs and will last much longer. And if necessary, power the PWM controller from 24 volts or more, since the microcircuit itself with a buffer stage has a power stabilizer.

AC Motor Speed ​​Controller

PWM controller 12 volt

Half Bridge DC Regulator Driver

Mini drill speed controller circuit

Diagrams and overview of 220V electric motor speed controllers

To smoothly increase and decrease the shaft rotation speed, there is a special device - a 220V electric motor speed controller. Stable operation, no voltage interruptions, long service life - the advantages of using an engine speed controller for 220, 12 and 24 volts.

  • Why do you need a frequency converter?
  • Application area
  • Selecting a device
  • IF device
  • Types of devices
    • Triac device
    • Proportional Signal Process

Why do you need a frequency converter?

The function of the regulator is to invert the voltage of 12, 24 volts, ensuring smooth start and stop using pulse width modulation.

Speed ​​controllers are included in the structure of many devices, as they ensure the accuracy of electrical control. This allows you to adjust the speed to the desired amount.

Application area

DC motor speed controller is used in many industrial and domestic applications. For example:

  • heating complex;
  • equipment drives;
  • welding machine;
  • electric ovens;
  • vacuum cleaners;
  • Sewing machines;
  • washing machines.

Selecting a device

In order to select an effective regulator, it is necessary to take into account the characteristics of the device and its intended purpose.

  1. Vector controllers are common for commutator motors, but scalar controllers are more reliable.
  2. An important selection criterion is power. It must correspond to that permitted on the unit used. It is better to exceed for safe operation of the system.
  3. The voltage must be within acceptable wide ranges.
  4. The main purpose of the regulator is to convert frequency, so this aspect must be selected according to the technical requirements.
  5. You also need to pay attention to the service life, dimensions, number of inputs.

IF device

  • AC motor natural controller;
  • drive unit;
  • additional elements.

The circuit diagram of the 12 V engine speed controller is shown in the figure. The speed is adjusted using a potentiometer. If pulses with a frequency of 8 kHz are received at the input, then the supply voltage will be 12 volts.

The device can be purchased at specialized sales points, or you can make it yourself.

AC speed controller circuit

When starting a three-phase motor at full power, current is transmitted, the action is repeated about 7 times. The current bends the motor windings, generating heat over a long period of time. A converter is an inverter that provides energy conversion. The voltage enters the regulator, where 220 volts are rectified using a diode located at the input. Then the current is filtered through 2 capacitors. PWM is generated. Next, the pulse signal is transmitted from the motor windings to a specific sinusoid.

There is a universal 12V device for brushless motors.

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The circuit consists of two parts - logical and power. The microcontroller is located on a chip. This scheme is typical for a powerful engine. The uniqueness of the regulator lies in its use with various types of engines. The circuits are powered separately; the key drivers require 12V power.

Types of devices

Triac device

The triac device is used to control lighting, power of heating elements, and rotation speed.

The controller circuit based on a triac contains a minimum of parts shown in the figure, where C1 is a capacitor, R1 is the first resistor, R2 is the second resistor.

Using a converter, power is regulated by changing the time of an open triac. If it is closed, the capacitor is charged by the load and resistors. One resistor controls the amount of current, and the second regulates the charging rate.

When the capacitor reaches the maximum voltage threshold of 12V or 24V, the switch is activated. The triac goes into the open state. When the mains voltage passes through zero, the triac is locked, and then the capacitor gives a negative charge.

Converters on electronic keys

Common thyristor regulators with a simple operating circuit.

Thyristor, works in alternating current network.

A separate type is the AC voltage stabilizer. The stabilizer contains a transformer with numerous windings.

DC stabilizer circuit

24 volt thyristor charger

To a 24 volt voltage source. The principle of operation is to charge a capacitor and a locked thyristor, and when the capacitor reaches voltage, the thyristor sends current to the load.

Proportional Signal Process

Signals arriving at the system input form feedback. Let's take a closer look using a microcircuit.

Chip TDA 1085

The TDA 1085 chip pictured above provides feedback control of a 12V, 24V motor without loss of power. It is mandatory to contain a tachometer, which provides feedback from the engine to the control board. The stabilization sensor signal goes to a microcircuit, which transmits the task to the power elements - to add voltage to the motor. When the shaft is loaded, the board increases the voltage and the power increases. By releasing the shaft, the tension decreases. The revolutions will be constant, but the power torque will not change. The frequency is controlled over a wide range. Such a 12, 24 volt motor is installed in washing machines.

With your own hands you can make a device for a grinder, wood lathe, sharpener, concrete mixer, straw cutter, lawn mower, wood splitter and much more.

Industrial regulators, consisting of 12, 24 volt controllers, are filled with resin and therefore cannot be repaired. Therefore, a 12V device is often made independently. A simple option using the U2008B chip. The controller uses current feedback or soft start. If the latter is used, elements C1, R4 are required, jumper X1 is not needed, but with feedback, vice versa.

When assembling the regulator, choose the right resistor. Since with a large resistor there may be jerks at the start, and with a small resistor the compensation will be insufficient.

Important! When adjusting the power controller, you need to remember that all parts of the device are connected to the AC network, so safety precautions must be observed!

Speed ​​controllers for single-phase and three-phase 24, 12 volt motors are a functional and valuable device, both in everyday life and in industry.

ENGINE SPEED CONTROL DIAGRAM

Regulator for AC motor

Based on the powerful triac BT138-600, you can assemble a circuit for an AC motor speed controller. This circuit is designed to regulate the rotation speed of electric motors of drilling machines, fans, vacuum cleaners, grinders, etc. The motor speed can be adjusted by changing the resistance of potentiometer P1. Parameter P1 determines the phase of the trigger pulse, which opens the triac. The circuit also performs a stabilization function, which maintains engine speed even under heavy load.

Schematic diagram of an AC motor regulator

For example, when the motor of a drilling machine slows down due to increased metal resistance, the EMF of the motor also decreases. This leads to an increase in voltage in R2-P1 and C3 causing the triac to open for a longer time, and the speed increases accordingly.

Regulator for DC motor

The simplest and most popular method of adjusting the rotation speed of a DC motor is based on the use of pulse width modulation ( PWM or PWM ). In this case, the supply voltage is supplied to the motor in the form of pulses. The repetition rate of the pulses remains constant, but their duration can change - so the speed (power) also changes.

To generate a PWM signal, you can take a circuit based on the NE555 chip. The simplest circuit of a DC motor speed controller is shown in the figure:

Schematic diagram of a constant power electric motor regulator

Here VT1 is an n-type field-effect transistor capable of withstanding the maximum motor current at a given voltage and shaft load. VCC1 is from 5 to 16 V, VCC2 is greater than or equal to VCC1. The frequency of the PWM signal can be calculated using the formula:

where R1 is in ohms, C1 is in farads.

With the values ​​indicated in the diagram above, the frequency of the PWM signal will be equal to:

F = 1.44/(50000*0.0000001) = 290 Hz.

It is worth noting that even modern devices, including those with high control power, are based on precisely such circuits. Naturally, using more powerful elements that can withstand high currents.

PWM - engine speed controllers on timer 555

The 555 timer is widely used in control devices, for example, in PWM - speed controllers for DC motors.

Anyone who has ever used a cordless screwdriver has probably heard a squeaking sound coming from inside. This is the whistling of the motor windings under the influence of the pulse voltage generated by the PWM system.

It is simply indecent to regulate the speed of an engine connected to a battery in another way, although it is quite possible. For example, simply connect a powerful rheostat in series with the motor, or use an adjustable linear voltage regulator with a large radiator.

A variant of the PWM regulator based on the 555 timer is shown in Figure 1.

The circuit is quite simple and is based on a multivibrator, albeit converted into a pulse generator with an adjustable duty cycle, which depends on the ratio of the charge and discharge rates of capacitor C1.

The capacitor is charged through the circuit: +12V, R1, D1, the left side of the resistor P1, C1, GND. And the capacitor is discharged along the circuit: upper plate C1, right side of resistor P1, diode D2, pin 7 of the timer, bottom plate C1. By rotating the slider of resistor P1, you can change the ratio of the resistances of its left and right parts, and therefore the charging and discharging time of capacitor C1, and, as a consequence, the duty cycle of the pulses.

Figure 1. PWM circuit - regulator on a 555 timer

This scheme is so popular that it is already available in the form of a set, as shown in the following figures.

Figure 2. Schematic diagram of a set of PWM regulators.

Timing diagrams are also shown here, but, unfortunately, the part values ​​are not shown. They can be seen in Figure 1, which is why it is shown here. Instead of bipolar transistor TR1, without altering the circuit, you can use a powerful field effect one, which will increase the load power.

By the way, another element has appeared in this diagram - diode D4. Its purpose is to prevent the discharge of the timing capacitor C1 through the power source and load - the motor. This ensures stabilization of the PWM frequency.

By the way, with the help of such circuits you can control not only the speed of a DC motor, but also simply an active load - an incandescent lamp or some kind of heating element.

Figure 3. Printed circuit board of a set of PWM regulators.

If you put in a little work, it is quite possible to recreate this using one of the programs for drawing printed circuit boards. Although, given the small number of parts, it will be easier to assemble one copy using a hinged installation.

Figure 4. Appearance of a set of PWM regulators.

True, the already assembled branded set looks quite nice.

Here, perhaps, someone will ask a question: “The load in these regulators is connected between +12V and the collector of the output transistor. But what about, for example, in a car, because everything there is already connected to the ground, the body, of the car?”

Yes, you can’t argue against the mass; here we can only recommend moving the transistor switch to the “positive” gap; wires. A possible version of such a scheme is shown in Figure 5.

Figure 6 shows the MOSFET output stage separately. The drain of the transistor is connected to the +12V battery, the gate just hangs 9raquo; in the air (which is not recommended), a load is connected to the source circuit, in our case a light bulb. This figure is shown simply to explain how a MOSFET transistor works.

In order to open a MOSFET transistor, it is enough to apply a positive voltage to the gate relative to the source. In this case, the light bulb will light up at full intensity and will shine until the transistor is closed.

In this figure, the easiest way to turn off the transistor is to short-circuit the gate to the source. And such a manual closure is quite suitable for checking the transistor, but in a real circuit, especially a pulse circuit, you will have to add a few more details, as shown in Figure 5.

As mentioned above, an additional voltage source is required to turn on the MOSFET transistor. In our circuit, its role is played by capacitor C1, which is charged via the +12V circuit, R2, VD1, C1, LA1, GND.

To open transistor VT1, a positive voltage from a charged capacitor C2 must be applied to its gate. It is quite obvious that this will only happen when transistor VT2 is open. And this is only possible if the optocoupler transistor OP1 is closed. Then the positive voltage from the positive plate of capacitor C2 through resistors R4 and R1 will open transistor VT2.

At this moment, the input PWM signal must be at a low level and bypass the optocoupler LED (this LED switching is often called inverse), therefore, the optocoupler LED is off and the transistor is closed.

To turn off the output transistor, you need to connect its gate to the source. In our circuit, this will happen when transistor VT3 opens, and this requires that the output transistor of the optocoupler OP1 be open.

The PWM signal at this time is at a high level, so the LED is not shunted and emits the infrared rays assigned to it, the optocoupler transistor OP1 is open, which as a result turns off the load - the light bulb.

One of the options for using such a scheme in a car is daytime running lights. In this case, motorists claim to use high beam lamps turned on at full intensity. Most often these designs are on a microcontroller. There are a lot of them on the Internet, but it’s easier to do it on the NE555 timer.

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5 common questions asked by beginning radio mechanics; 5 best transistors for regulators, circuit composition test

Regulator electrical voltage is needed so that the voltage value can stabilize. It ensures reliable operation and longevity of the device.

Regulator consists of several mechanisms.

TEST:

The answers to these questions will allow you to find out the composition of the 12 volt voltage regulator circuit and its assembly.
  1. What resistance should the variable resistor have?
  1. How should the wires be connected?

a) Terminals 1 and 2 – power, 3 and 4 – load

  1. Do I need to install a radiator?
  1. The transistor must be

Answers:

Option 1. The resistor resistance is 10 kOhm - this is the standard for installing the regulator, the wires in the circuit are connected according to the principle: terminals 1 and 2 for power, 3 and 4 for load - the current will be distributed correctly to the required poles, a radiator needs to be installed - to protect against overheating, the transistor is used CT 815 – this will always do. In this embodiment, the constructed circuit will work, the regulator will begin to work.

Option 2. A resistance of 500 kOhm is too high, the smoothness of the sound in operation will be disrupted, and it may not work at all, terminals 1 and 3 are the load, terminals 2 and 4 are power, a radiator is needed, in the circuit where there was a minus there will be a plus, any transistor can really be used whatever. The regulator will not work due to the fact that the circuit is assembled incorrectly.

Option 3. The resistance is 10 kOhm, wires are 1 and 2 for load, 3 and 4 for power, the resistor has a resistance of 2 kOhm, the transistor is KT 815. The device will not be able to work, since it will overheat greatly without a radiator.

How to connect 5 parts of a 12 volt regulator.

Variable resistor 10 kOhm.

It's variable resistor 10 rooms Changes the current or voltage in an electrical circuit, increases resistance. This is what regulates the voltage.

Radiator. Needed to cool devices in case they overheat.

Resistor for 1 com. Reduces the load on the main resistor.


Transistor. The device increases the strength of vibrations. In the regulator it is needed to obtain high-frequency electrical oscillations


2 wiring. They are necessary for electric current to flow through them.

Let's take it transistor And resistor. Both have 3 branches.

Two operations are carried out:

  1. We connect the left end of the transistor (we do it with the aluminum part down) to the end that is in the middle of the resistor.
  2. And we connect the branch of the middle of the transistor to the right branch of the resistor. They need to be soldered to each other.

The first wire must be soldered to what happened in operation 2.

The second one needs to be soldered to the remaining end transistor.


We screw the connected mechanism to the radiator.

We solder a 1kOhm resistor to the outer legs of the variable resistor and transistor.

Scheme ready.


DC motor speed controller using 2 14 volt capacitors.

The practicality of such engines proven, they are used in mechanical toys, fans, etc. They have low current consumption, so voltage stabilization is required. Often there is a need to adjust the rotation speed or change the speed of the engine to adjust the fulfillment of the goal presented to some type electric motor any model.

This task will be performed by a voltage regulator that is compatible with any type of power supply.

To do this, you need to change the output voltage, which does not require a large load current.

Required parts:

  1. 2 Capacitors
  2. 2 variable resistors

Connecting the parts:

  1. We connect the capacitors to the regulator itself.
  2. The first resistor is connected to the negative of the regulator, the second to ground.

Now change the engine speed of the device according to the user’s wishes.

Voltage regulator on 14 volts ready.

Simple 12 volt voltage regulator

12 volt speed controller for motor with brake.

  • Relay - 12 volts
  • Theristor KU201
  • Transformer for powering the motor and relay
  • Transistor KT 815
  • Wiper valve 2101
  • Capacitor

It is used to regulate the wire feed, so it has a motor brake implemented using a relay.

We connect 2 wires from the power supply to the relay. The relay is supplied with plus.

Everything else is connected according to the principle of a conventional regulator.

The scheme fully provided 12 volts for the motor.

Power regulator on triac BTA 12-600

Triac- a semiconductor device, classified as a type of thyristor and used for current switching purposes. It operates on alternating voltage, unlike a dinistor and a conventional thyristor. The entire power of the device depends on its parameter.

Answer to the question. If the circuit were assembled using a thyristor, a diode or diode bridge would be needed.

For convenience, the circuit can be assembled on a printed circuit board.

Plus capacitor you need to solder the triac to the control electrode, it is located on the right. Solder the minus to the third outer pin, which is on the left.

To the manager electrode triac, solder a resistor with a nominal resistance of 12 kOhm. A substring resistor must be connected to this resistor. The remaining pin must be soldered to the central leg of the triac.

To the minus capacitor, which is soldered to the third terminal of the triac, you must attach the minus from the rectifier bridge.

Plus of the rectifier bridge to the central terminal triac and to the part to which the triac is attached to the radiator.

We solder 1 contact from the cord with a plug to the required device. A 2 contact to the AC voltage input on the rectifier bridge.

It remains to solder the remaining contact of the device to the last contact of the rectifier bridge.

The circuit is being tested.

We connect the circuit to the network. Using a trimmer resistor, the power of the device is adjusted.

Power can be developed up to 12 volts for cars.

Dinistor and 4 types of conductivity.

This device is called trigger diode. Has little power. There are no electrodes in its interior.

The dinistor opens when the voltage increases. The speed at which voltage increases is determined by the capacitor and resistors. All adjustments are made through it. Works on direct and alternating current. You don’t have to buy it, it is in energy-saving lamps and is easy to get from there.

It is not often used in circuits, but in order not to spend money on diodes, a dinistor is used.

It contains 4 types: P N P N. This is electrical conductivity itself. An electron-hole junction is formed between 2 adjacent regions. There are 3 such transitions in the dinistr.

Scheme:

Connecting capacitor. It starts charging with 1 resistor, the voltage is almost equal to that in the network. When the voltage in the capacitor reaches the level dinistor, it will turn on. The device starts working. Don't forget about the radiator, otherwise everything will overheat.

3 important terms.

Voltage regulator– a device that allows you to adjust the output voltage to the device for which it is needed.

Scheme for the regulator– a drawing depicting the connection of parts of a device into one whole.

Car generator– a device that uses a stabilizer ensures the conversion of crankshaft energy into electrical energy.

7 basic diagrams for assembling a regulator.


SNIP

Using 2 transistors. How to assemble a current stabilizer.

Resistor 1kOhm is equal to the current stabilizer for a 10Ohm load. The main condition is that the supply voltage is stabilized. Current depends on voltage according to Ohm's law. The load resistance is much less than the current limiting resistor.

Resistor 5 watt, 510 ohm

Variable resistor PPB-3V, 47 Ohm. Consumption – 53 milliamps.

Transistor KT 815, installed on the radiator, the base current of this transistor is set by a resistor with a nominal value of 4 and 7 kOhm.


SNIP


SNIP

It's also important to know

  1. There is a minus sign on the diagram, so that it is in operation, the transistor must be an NPN structure. You cannot use PNP because a minus will be a plus.
  2. The voltage needs to be constantly adjusted
  3. What is the current value in the load, you need to know this in order to regulate the voltage and the device does not stop working
  4. If the potential difference is greater than 12 volts at the output, the energy level will decrease significantly.

Top 5 transistors

Different types transistors are used for different purposes, and there is a need to select it.

  • KT 315. Supports NPN structure. Released in 1967 but still in use today. Works in dynamic mode and in key mode. Ideal for low power devices. More suitable for radio components.
  • 2N3055. Best suited for audio mechanisms, amplifiers. Works in dynamic mode. Easy to use for 12 volt regulator. Conveniently attaches to the radiator. Operates at frequencies up to 3 MHz. Although the transistor can only withstand up to 7 amperes, it pulls powerful loads.
  • KP501. The manufacturer intended it to be used in telephones, communication mechanisms and radio electronics. Through it, devices are controlled at minimal cost. Converts signal levels.
  • Irf3205. Suitable for automobiles, enhances high frequency inverters. Supports significant current levels.
  • KT 815. Bipolar. Has an NPN structure. Works with low frequency amplifiers. Consists of a plastic body. Suitable for pulse devices. Often used in generator circuits. The transistor was made a long time ago and still works today. There is even a chance that it is in an ordinary house where old appliances lie, you just need to take them apart and see if they are there.

3 mistakes and how to avoid them.

  1. Legs transistor and the resistor are completely soldered to each other. To avoid this, you need to carefully read the instructions.
  2. Even though it was staged radiator, The device has overheated. This is due to the fact that when the parts are soldered, overheating occurs. For this you need legs transistor hold with tweezers to remove heat.
  3. Relay did not work after repair. Drives out the wire after releasing the button. The wire stretches by inertia. This means the electric brake is not working. We take a relay with good contacts and connect it to the button. Connect the wires for power. When no voltage is applied to the relay, the contacts become closed, so the winding closes on itself. When voltage (plus) is applied to the relay, the contacts in the circuit change and voltage is supplied to the motor.

Answers to 5 Frequently Asked Questions

  • Why input voltage higher than the output?

All stabilizers work on this principle; with this type of operation, the voltage returns to normal and does not fluctuate from its prescribed values.

  • Can it kill electric shock in case of a problem or error?

No, it won’t electrocute you, 12 volts is too low for that to happen.

  • Is a permanent one needed? resistor? And if necessary, then for what purposes?

Not required, but used. It is needed in order to limit the base current of the transistor when the variable resistor is in the extreme left position. And also, in its absence, the variable may burn out.

  • Is it possible to use the diagram BANK instead of a resistor?

If, instead of a variable resistor, you include an adjustable KREN circuit, which is often used, you will also get a voltage regulator. But there is a mistake: low efficiency. Because of this, its own energy consumption and heat dissipation are high.

  • Resistor It lights up, but nothing turns. What to do?

The resistor must be 10 kOhm. It is advisable to use KT 315 transistors (old model) - they are yellow or orange with a letter designation.

This DIY circuit can be used as a speed controller for a 12V DC motor with a current rating of up to 5A, or as a dimmer for 12V halogen and LED lamps up to 50W. Control is carried out using pulse width modulation (PWM) at a pulse repetition rate of about 200 Hz. Naturally, the frequency can be changed if necessary, selecting for maximum stability and efficiency.

Most of these structures are assembled at a much higher cost. Here we present a more advanced version that uses a 7555 timer, a bipolar transistor driver and a powerful MOSFET. This design provides improved speed control and operates over a wide load range. This is indeed a very effective scheme and the cost of its parts when purchased for self-assembly is quite low.

The circuit uses a 7555 Timer to create a variable pulse width of about 200 Hz. It controls transistor Q3 (via transistors Q1 - Q2), which controls the speed of the electric motor or light bulbs.



There are many applications for this circuit that will be powered by 12V: electric motors, fans or lamps. It can be used in cars, boats and electric vehicles, in model railways and so on.


12 V LED lamps, for example LED strips, can also be safely connected here. Everyone knows that LED bulbs are much more efficient than halogen or incandescent bulbs and will last much longer. And if necessary, power the PWM controller from 24 volts or more, since the microcircuit itself with a buffer stage has a power stabilizer.

Many electronic circuits use active cooling systems with fans. Most often, their motors are controlled by a microcontroller or other specialized chip, and the rotation speed is controlled using PWM. This solution is characterized by not very smooth operation, can lead to unstable operation of the fan, and in addition, creates a lot of interference.

An analog fan speed controller has been developed for the needs of high-quality audio equipment. The circuit is useful in the construction of low-frequency amplifiers with an active cooling system and allows for smooth adjustment of fan speed depending on temperature. Performance and power depend mainly on the output transistor; tests were carried out with output currents up to 2 A, which allows you to connect even several large 12 V fans. Naturally, this device can also be used to control conventional DC motors, increasing the supply voltage if necessary. Although for very powerful engines you will have to use soft start systems tehprivod.su/katalog/ustroystva-plavnogo-puska

Schematic diagram of the motor speed controller

The circuit consists of two parts: a differential amplifier and a voltage stabilizer. The first part deals with temperature measurement and provides a voltage proportional to the temperature when it exceeds a set threshold. This voltage is the control voltage for the voltage stabilizer, the output of which controls the power supply to the fans.

The circuit diagram of the DC motor speed controller is shown in the figure. The basis is the comparator U2 (LM393), which works in this configuration as a regular operational amplifier. Its first part, U2A, works as a differential amplifier, whose operating conditions are determined by resistors R4-R5 (47k) and R6-R7 (220k). Capacitor C10 (22pF) improves the stability of the amplifier, and R12 (10k) pulls the comparator output to the power supply positive.

A voltage is applied to one of the inputs of the differential amplifier, which is generated through a divider consisting of R2 (6.8k), R3 (680 Ohms) and PR1 (500 Ohms), and is filtered using C4 (100nF). The second input of this amplifier receives voltage from the temperature sensor, which in this case is one of the connectors of transistor T1 (BD139), polarized with a small current using R1 (6.8k).

Capacitor C2 (100nF) was added to filter the voltage from the temperature sensor. The polarity of the sensor and reference voltage divider is set by regulator U1 (78L05) along with capacitors C1 (1000uF/16V), C3 (100nF) and C5 (47uF/25V), providing a stabilized voltage of 5 V.

The U2B comparator works as a classic error amplifier. It compares the voltage from the output of the differential amplifier with the output voltage using R10 (3.3k), R11 (47 ohms) and PR2 (200 ohms). The executive element of the stabilizer is transistor T2 (IRF5305), the base of which is controlled by the divider R8 (10k) and R9 (5.1k).

Capacitor C6 (1uF) and C7 (22pF) and C9 (10nF) improve feedback loop stability. Capacitor C8 (1000uF/16V) filters the output voltage, it has a significant impact on system stability. The output connector is AR2 (TB2), and the power connector is AR1 (TB2).

Thanks to the use of a low on-resistance output transistor, the circuit has a very low voltage dropout - about 50 mV at an output current of 1 A, which does not require a higher voltage power supply to drive 12 V fans.

In most cases, the popular operational amplifier LM358 can be used as U2, although the output parameters will be slightly worse.

Regulator assembly

Installation should begin with the installation of two jumpers, then all resistors and small ceramic capacitors should be installed.

In most cases, both of these elements will be mounted at the bottom of the board on legs that are bent at a 90-degree angle. This arrangement will allow them to be screwed directly to the radiator (be sure to use insulating gaskets).

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