Electronic voltage regulator of the car's onboard network. Two simple voltage regulators Electronic voltage regulators

Electromechanical, in which, with the help of vibrating contacts, the current in the excitation winding of the alternator changes. The operation of the vibrating contacts is ensured in such a way that with an increase in the voltage of the on-board network, the current in the excitation winding decreases. However, vibrating voltage regulators maintain voltage with an accuracy of 5-10%, because of this, the durability of the battery and car lighting lamps is significantly reduced.
Electronic voltage regulators of the on-board network type Ya112, which are popularly called "chocolate". The disadvantages of this regulator are known to everyone - low reliability due to low switching current of 5A and the installation site right on the generator, which leads to overheating of the regulator and its failure. The accuracy of maintaining the voltage remains, despite the electronic circuitry, very low and amounts to 5% of the rated voltage.

That's why I decided to make a device that is free from the above disadvantages. The regulator is easy to set up, the voltage maintenance accuracy is 1% of the rated voltage. The circuit shown in Fig. 1 has been tested on many vehicles, including trucks for 2 years and has shown very good results.

Fig.1.

Principle of operation

When the ignition switch is turned on, +12V voltage is applied to the electronic regulator circuit. If the voltage supplied to the zener diode VD1 from the voltage divider R1R2 is not enough for its breakdown, then the transistors VT1, VT2 are in the closed state, and VT3 is in the open state. The maximum current flows through the excitation winding, the output voltage of the generator begins to grow, and when it reaches 13.5 - 14.2V, a breakdown of the zener diode occurs.

Due to this, transistors VT1, VT2 open, respectively, the transistor VT3 closes, the excitation winding current decreases and the generator output voltage decreases. Reducing the output voltage by about 0.05 - 0.12V is enough for the zener diode to switch to the locked state, after which the transistors VT1, VT2 close, and the transistor VT3 opens and current begins to flow through the excitation winding again. This process is continuously repeated with a frequency of 200 - 300 Hz, which is determined by the inertia of the magnetic flux.

Design

In the manufacture of an electronic regulator, special attention should be paid to heat removal from the VT3 transistor. This transistor, operating in the key mode, no less releases significant power, so it should be mounted on a radiator. The remaining parts can be placed on a printed circuit board attached to the heatsink.

Thus, it turns out very compact design. Resistor R6 must be at least 2W. Diode VD2 should have a forward current of about 2A and a reverse voltage of at least 400V, KD202Zh is best suited, but other options are possible. It is desirable to use transistors those indicated on circuit diagram, especially VT3. Transistor VT2 can be replaced by KT814 with any letter index. It is desirable to install a VD1 zener diode with a KS series with a stabilization voltage of 5.6-9V (type KS156A, KS358A, KS172A), while the accuracy of maintaining the voltage will increase.

Setting

A properly assembled voltage regulator does not need special settings and ensures the stability of the on-board network voltage of about 0.1 - 0.12V, when the engine speed changes from 800 to 5500 rpm. The easiest way to make adjustments is on a stand, consisting of adjustable block power supply 0 - 17V and incandescent bulbs 12V 5-10W. The positive output of the power supply is connected to the “+” terminal of the regulator, the negative output of the power supply is connected to the “Common” terminal, and the incandescent bulb is connected to the “Sh” terminal and the “Common” terminal of the regulator.

The setting is reduced to the selection of the resistor R2, which is changed within 1-5 kOhm, and the threshold is reached at the level of 14.2V. This is the supported voltage of the on-board network. It is impossible to increase it above 14.5V, since this will drastically reduce the battery life.

Phase voltage regulators quite common in everyday life. Their most common area of ​​application is dimming devices.
Below are a few simple voltage adjustment circuits for self-repetition for beginner radio amateurs.

Attention!! All circuits are designed to work with a mains voltage of 220 volts, so be careful when assembling and setting up!!

This scheme is the most common in various foreign household appliances, as the simplest and most reliable, but the following scheme has become more widespread in our country:

The thyristor KU202N was most often used as a thyristor, but it should be noted that if you plan to use a powerful load, then the thyristor will need to be installed on a radiator.

All the designs considered are very simple, reliable, perfectly regulate the voltage, but are not without flaws, due to which enthusiasts are not translated to offer their circuits, albeit more complex ones. The main problem of the above circuits is the inverse dependence of the phase angle on the level of the supply voltage, i.e. when the voltage drops in the network, the phase angle of the opening of the thyristor or triac increases, which leads to a disproportionate decrease in the voltage at the load. A small decrease in voltage will cause a noticeable decrease in the brightness of the lamps and vice versa. If there are small ripples in the mains, for example, from the operation of a welding machine, the flickering of the lamps will become much more noticeable.

The appearance of semiconductor devices capable of switching high powers when operating in the key mode led to the use of transistor and thyristor regulators to regulate the voltage of aircraft generators. Voltage regulation is carried out by changing the average excitation current. In most transistor voltage regulator circuits, the circuit diagram of the final stage has the form shown in Fig. 4.3.a).

Rice. 4.3. a) Scheme of switching on the electronic regulator; b) the shape of the control signal and the average current in the OVG.

Regulator circuits differ from each other in the control circuits of a pulse element, the role of which is played by a powerful transistor connected in series with the excitation winding and operating in key mode. When the transistor is in the closed state, we can assume that the resistance of the emitter - collector circuit is very high - "the key is closed." If the transistor operates in saturation mode (is in the open state) - “the key is open”, then the resistance is very small. . The control circuit generates rectangular pulses (Fig. 4.3.b). When a rectangular pulse is applied from the control circuit, the transistor opens and current begins to flow through the excitation winding of the generator. But since the excitation winding is an inductance, the increase in current in it will be exponential. When the impact of the pulse is terminated, the excitation current will also decrease not instantly, but exponentially, i.e. when the transistor is open, magnetic energy accumulates in the poles of the generator, and in the pause of the control current, the current in the excitation winding continues to flow due to the accumulated energy in the magnetic field. The average current is regulated by changing the duty cycle of the pulses. When the generator voltage deviates from the set value, for example, when it increases, the pulse duration, and, accordingly, the time the transistor is in the open state, decreases, which leads to a decrease in the average excitation current of the generator exciter, and the generator voltage returns to the previous value. When the generator voltage decreases, the time the transistor is in the open state increases, the average excitation current of the exciter and, consequently, the generator voltage increase.

Thus, a decrease in the duty cycle leads to an increase in the average current, and vice versa. The electronic equipment of the ERN allows you to expand the functions of the regulator, for example, on the L410 aircraft, it protects the network from increasing the generator voltage and limits the maximum generator current when the engine is started.

CONTROL AND PROTECTION OF DC GENERATORS

Control operations include: remote switching on and off of generators; automatic switching on of generators to the load with the correct polarity and a certain ratio of the voltages of the generators and the on-board network. Connection of generators to the onboard network is controlled automatically.

During operation, there may be cases of failures of elements of generation systems, leading to disruption of the normal operation of the SES. In order to prevent possible serious consequences that abnormal modes can lead to, apply different kinds protection. DC SES uses protection against undervoltage and overvoltage, switching on the generator with the wrong polarity and against short circuits.

Operations of control and protection against undervoltage (against reverse currents) and against turning on the generator with the wrong polarity are performed by a complex device - a differential-minimum relay. Overvoltage protection is provided by overvoltage protection circuit breakers.

Many people know about such a device as a generator voltage regulator, but not everyone is able to say what principles underlie its operation and how diagnostics can be carried out. It is worth noting that this device is extremely important, because it is used to stabilize the voltage at the output of the generator. Imagine how the engine works in the process of movement. Its revolutions are constantly changing, and in a wide range, ranging from 700-900 rpm, and ending with five, seven or even ten thousand. As a result, the frequency of rotation of the generator rotor also varies over a wide range. And at any speed, a stable voltage must be maintained, which will be enough to charge battery. If there are any defects, then a thorough check of the generator voltage regulator is required.

Mechanical voltage regulators

The history of the automotive industry goes back more than a hundred years, during which time many designs have been invented and implemented that improve the performance of all units. Among them is a relay-regulator, since a modern machine will not be able to work normally without it. Initially, mechanical devices were used, which were based on an electromagnetic relay. For example, the voltage regulator of the VAZ generator of the first models was just that.

He, as it turned out later, has no pluses, quite often there are shortcomings. Moreover, the main disadvantage is low reliability due to the presence of moving contacts. They are erased over time, as the device works constantly, without stopping. In addition, sometimes it is required to carry out adjustment work, which does not have a very good effect on the operation of the car. Modernity dictates the rule that the machine must be serviced in a timely manner in service centers. And the driver should not be able to carry out complex repairs, he only needs the ability to drive a car and change a wheel (this is the maximum).

Electronic relay-regulators

For the reasons indicated above, electronic type voltage regulators have become widespread. Progress does not stand still, so key transistors, triacs, thyristors have replaced electromagnetic relays. They have very high reliability, since there are no mechanical contacts, instead of which there is a semiconductor crystal. Of course, the production technology of such devices should be thought out. Otherwise, the semiconductor may fail. The voltage regulator of this type of generator is checked quite simply, you just need to take into account its features.

When compared with the previous, mechanical type of relay-regulators, one feature can be seen - electronic ones are produced in the same housing with brushes. This saves space, and most importantly, facilitates the replacement and diagnostics procedure. A special feature of electronic types is the accuracy of voltage regulation. The properties of a semiconductor do not change during operation. Therefore, the voltage at the output of the generator will always be the same. But it is worth talking about the method of regulation, about how the whole process takes place. And it is quite interesting, you will have to consider in general terms the design of the generator.

What elements does a car generator consist of

The base is the body, otherwise it is called the stator. It is the fixed part of any electrical machine. The stator has a winding. In automotive generators, it consists of three parts. The thing is that a three-phase alternating voltage is generated at the output, its value is about 30 volts. The reason for using this design is to reduce ripple, since the phases overlap each other, as a result, a direct current appears after the rectifier. Six semiconductor diodes are used for voltage conversion. They are unidirectional. If a breakdown occurs, then determining this with a tester is quite simple.

But there will be no voltage at the output of the stator winding, unless one condition is taken into account - a magnetic field is needed, and a moving one. It is not difficult to make it, it is enough to wind the winding on a metal anchor and apply power to it. But now the question of voltage stabilization arises. It makes no sense to do this at the output, since the elements will need to be very powerful, because the currents are large. But here one feature of electrical machines comes to the aid of designers - if a stabilized voltage is applied to the rotor winding, then the magnetic field will not change. Consequently, the voltage at the output of the generator also stabilizes. The VAZ 2107 generator works in the same way, the voltage regulator of which operates on the same principles as those of the "tens".

Voltage Regulator Components

Modern cars are equipped with fairly simple designs. They are non-separable, two elements are combined in one housing - the regulator itself and graphite brushes that transmit the supply voltage to the rotor winding of the generator. Moreover, electronic types of devices can be of two types. For example, the VAZ-2110 generator voltage regulator manufactured in the late 90s was made on a small circuit board. Modern devices are made using a single semiconductor crystal, in which all the elements are located. You can even say that this is a small chip.

Graphite brushes are connected to the terminals of the circuit board or semiconductor element. Voltage is supplied to them from the battery through a lamp, which is necessary for diagnosing the generator. Please note that you can not put LED elements in its place, since they have no internal resistance. Roughly speaking, the incandescent lamp also works as a fuse. If the thread burns out, then the voltage supply to the rotor winding stops, the generator stops working. If the lamp lights up, then there is a breakdown. Either the brushes are worn out, or the belt is broken, but sometimes it also happens that the semiconductor diodes in the rectifier fail. In this case, it is necessary to replace the generator voltage regulator with a new one.

How to remove the regulator

If the fault is only in the voltage regulator, then there is little work to replace it. You will also need a special tool - one screwdriver is enough. It is not necessary to completely disassemble the generator, since the brushes with the voltage regulator are located on its back cover.

You don't even need to loosen the belt. It is necessary to remove the generator voltage regulator 2110 in two cases:

1. The brushes are completely worn out.
2. A breakdown has occurred in the semiconductor.

Options for checking the device will be presented below. First, disconnect the battery. The fact is that a power wire goes from it to the generator, there is no protection on it, because it is used to charge the battery. And the current consumption of this circuit is very high. There is one connector on the regulator housing, disconnect the wire from it. Now you can unscrew the two mounting bolts. After that, the generator voltage regulator can be easily removed from back cover. It's time to check it out.

Voltage Regulator Diagnostics

First of all, pay attention to the condition of the brushes - if their length is less than 0.5 cm, then it is necessary to change the assembly assembly. Don't invent the wheel. It makes no sense to solder new brushes, since reliability will only suffer from this. Since there are several ways to check the generator voltage regulator, it’s worth starting with the most difficult thing - removing the device. For diagnostics, you will need a power supply, at the output of which the voltage can be changed within 10-18 Volts.

You also need an incandescent lamp. Its electrical parameters are as follows: supply voltage - 12 volts, power - 2-3 watts. Serve as follows:

1. Positive output to the connector in the regulator housing (it is the only one on new samples).
2. Minus the common plate.

The incandescent lamp is switched on between two brushes. The procedure is as follows:

1. When a voltage of 12-12.5 volts is applied, the incandescent lamp should be on.
2. At voltages above 15 volts, it should go out.

If it lights up at any supply voltage, or does not light up in any of these cases, then there is a breakdown of the regulator and it needs to be replaced.

How to make a diagnosis without removal?

It is not recommended to carry out such a check, since it is not possible to assess the condition of the brush assembly. But cases are different, so even such a diagnosis can bear fruit. To work, you will need a multimeter or, if there is none, an incandescent lamp. The main thing for you is to measure the voltage in the vehicle's on-board network, to determine if there are any surges. But they can be seen while driving. For example, flashing light when the engine speed changes.

But measurements taken using a multimeter or a voltmeter with an extended scale will be more accurate. Start the engine and turn on the low beam. Connect a multimeter to the battery terminals. The voltage should not exceed 14.8 volts. But it is also impossible for it to fall below 12. If it is not in the allowed range, then there is a breakdown of the voltage regulator. It is possible that the contacts at the connection points of the device with the generator are broken, or the wire contacts are oxidized.

Modernization of the regulator circuit

How complete the battery will be charged depends on the voltage regulator. Unfortunately, the simple constructions described above have a wide range of parameters. Therefore, buying three copies of the same devices in the same store, you will get a different output voltage. And this is a fact, no one will argue. If the battery does not have enough charge, then it will lose its capacity in a short time. And it won't start the engine. You will need to restore it only with a stationary charger.

But you can install a three-level generator voltage regulator, which allows you to change the characteristics by simply switching the toggle switch. In his circuit there are two semiconductors, in which the characteristics are slightly different. This makes it possible to adjust the output voltage. When one semiconductor is turned on, 14.5 volts appears at the output, and if another is put into the circuit, it will be slightly higher. The use of such a device is relevant in the winter, when the battery capacity decreases and additional charging is required.

How to install a three-level regulator?

For this procedure, you will need a small set of tools. You need a screwdriver, heat shrink insulation, self-tapping screws, it is possible that you will need a drill with a 2-4 mm drill. So, everything is in order. First of all, you need to unscrew the two bolts that secure the brush assembly and the regulator. In its place, you need to put a new one that comes with the kit. Its difference from a simple one is that there are only brushes there, semiconductors are located in a separate block. You need to place the second node near the generator, on the car body.

To do this, make small holes for fastening. It is worth noting that the block with semiconductors needs additional cooling. Therefore, it will be necessary to install it on an aluminum radiator, only after that to make fasteners to the body elements. If sufficient cooling is not provided, then the device may fail, as well as a violation of its operation - the regulation will not occur correctly. After finishing the fastening work, connect the two nodes with wires, conduct insulation. It is advisable to fasten the connecting wires with the help of clamps-screeds to the existing bundles.

Is it possible to make a three-level regulator yourself?

If you are familiar with radio engineering, you can find a cathode and an anode on a diode, then it will not be difficult for you to make such a device yourself. The question is, does it make sense. You will need two Schottky diodes to make. If you have them, then the price of the structure will be scanty. But if you have to buy them (and it is not known at what price), then you can compare the costs with the cost of a finished three-level regulator. The three-level type generator voltage regulator circuit is simple, anyone who knows how to handle a soldering iron can repeat it.

To implement your idea, you will also need a plastic case. You can also use aluminum, it will even be better, since cooling will be more efficient. It is only desirable to cover all surfaces with a layer of insulation so that the contacts do not close to the case when driving. You will also need to install a switch that will switch semiconductor elements. The work on installing the device on a car is similar to that described in the previous paragraph. It is also worth noting that you still need to purchase a brush assembly.

conclusions

Do not neglect such a device as the voltage regulator of a car generator. The battery life depends on its quality and condition. And if there are any defects in the device, then it must be replaced. Monitor the condition of this element, if necessary, clean the contacts so that failures do not appear. The generator is located in the lower part of the engine compartment, and if there is no mudguard, then a lot of water and dirt gets on it in bad weather. And this leads to the appearance of defects, not only in the voltage regulator, but even in the stator and rotor windings. Therefore, car care is necessary for the normal functioning of all systems. And before checking the generator voltage regulator, conduct a thorough inspection and clean all structural elements from contamination.

8 basic do-it-yourself regulator circuits. Top 6 brands of regulators from China. 2 schemes. 4 Most Asked Questions about Voltage Regulators. + TEST for self-control

Voltage regulator- This is a specialized electrical device designed to smoothly change or adjust the voltage that feeds an electrical device.

Voltage regulator

Important to remember! Devices of this type are designed to change and adjust the supply voltage, not current. The current is regulated by the payload!

TEST:

4 questions about voltage regulators

1. What is the regulator for?

a) Change in voltage at the output of the device.

b) Breaking the electric circuit

1. What determines the power of the regulator:

a) From the input current source and from the executive body

b) On the size of the consumer

1. The main parts of the device, assembled by hand:

a) Zener diode and diode

b) Triac and thyristor

1. What are 0-5 volt regulators for:

a) Power the microcircuit with a stabilized voltage

b) Limit the current consumption of electric lamps

Answers.

2 The most common do-it-yourself pH schemes 0-220 volts

Scheme No. 1.

The simplest and most convenient voltage regulator to use is regulator on thyristors connected back to back. This will produce a sinusoidal output signal of the required magnitude.

The input voltage of up to 220V is supplied to the load through the fuse, and through the second conductor, through the power button, the sinusoidal half-wave enters the cathode and anode thyristors VS1 and VS2. And through the variable resistor R2, the output signal is adjusted. Two diodes VD1 and VD2 leave behind only a positive half-wave arriving at the control electrode of one of thyristors, which leads to its discovery.

Important! The higher the current signal on the thyristor key, the stronger it will open, that is, the more current it can pass through itself.

An indicator light is provided to control the input power, and a voltmeter is used to adjust the output power.

Scheme No. 2.

A distinctive feature of this circuit is the replacement of two thyristors with one triac. This simplifies the circuit, makes it more compact and easier to manufacture.

In the circuit, there is also a fuse and a power button, and an adjusting resistor R3, and it controls the base of the triac, this is one of the few semiconductor devices with the ability to work with alternating current. current passing through resistor R3, acquires a certain value, it will control the degree of opening triac. After that, it is rectified on the diode bridge VD1 and through the limiting resistor it enters the key electrode of the triac VS2. The remaining elements of the circuit, such as capacitors C1, C2, C3 and C4, serve to dampen the ripples of the input signal and filter it from extraneous noise and unregulated frequencies.

How to avoid 3 common mistakes when working with a triac.

1. The letter, after the code designation of the triac, indicates its maximum operating voltage: A - 100V, B - 200V, C - 300V, G - 400V. Therefore, you should not take a device with the letters A and B to adjust 0-220 volts - such a triac will fail.
2. The triac, like any other semiconductor device, gets very hot during operation, you should consider installing a radiator or an active cooling system.
3. When using a triac in load circuits with high current consumption, it is necessary to clearly select the device for the stated purpose. For example, a chandelier in which 5 light bulbs of 100 watts are installed will consume a total current of 2 amperes. When choosing from the catalog, it is necessary to look at the maximum operating current of the device. So triac The MAC97A6 is rated at only 0.4 amps and will not withstand such a load, while the MAC228A8 is capable of passing up to 8 A and will be suitable for this load.

3 Highlights in the manufacture of powerful pH and do-it-yourself current

The device controls loads up to 3000 watts. It is built on the use of a powerful triac, and it controls the shutter or key dinistor.

Dinistor- this is the same as the triac, only without the control output. If a triac opens and begins to pass current through itself, when a control voltage appears on its base and remains open until it disappears, then dinistor will open if a potential difference appears between its anode and cathode above the opening barrier. It will remain unlocked until the current between the electrodes falls below the blocking level.

As soon as a positive potential hits the control electrode, it opens and passes an alternating current, and the stronger this signal is, the higher the voltage between its terminals, and hence at the load. To regulate the degree of opening, a decoupling circuit is used, consisting of a dinistor VS1 and resistors R3 and R4. This circuit sets the current limit on the key triac, and capacitors smooth out ripples on the input signal.

2 basic principles in the manufacture of PH 0-5 volts

1. To convert the input high potential to a low constant, special microcircuits of the LM series are used.
2. The chips are powered only by direct current.

Let us consider these principles in more detail and analyze a typical regulator circuit.

The LM series ICs are designed to step down high DC voltage to low values. To do this, there are 3 outputs in the device case:

• The first output is the input signal.
• The second output is the output signal.
• The third output is the control electrode.

The principle of operation of the device is very simple - the input high voltage of a positive value is fed to the input output and then converted inside the microcircuit. The degree of transformation will depend on the strength and magnitude of the signal on the control "leg". In accordance with the master pulse, a positive voltage will be created at the output from 0 volts to the limit for this series.

The input voltage, not higher than 28 volts and necessarily rectified, is supplied to the circuit. You can take it from the secondary winding of the power transformer or from a high voltage regulator. After that, a positive potential is applied to the output of the microcircuit 3. Capacitor C1 smoothes the ripple of the input signal. A variable resistor R1 of 5000 ohms sets the output signal. The higher the current that it passes through itself, the higher the microcircuit opens. The output voltage of 0-5 volts is taken from output 2 and through the smoothing capacitor C2 enters the load. The higher the capacitance of the capacitor, the smoother it is at the output.

Voltage regulator 0 - 220v

Top 4 stabilizing microcircuits 0-5 volts:

1. KR1157- a domestic microcircuit, with an input signal limit of up to 25 volts and a load current of not more than 0.1 amperes.
2. 142EN5A- a microcircuit with a maximum output current of 3 amperes, no more than 15 volts are applied to the input.
3. TS7805CZ- a device with permissible currents up to 1.5 amperes and increased input voltage up to 40 volts.
4. L4960 – pulse chip with a maximum load current of up to 2.5 A. The input voltage should not exceed 40 volts.

pH on 2 transistors

This type is used in circuits of especially powerful regulators. In this case, the current to the load is also transmitted through the triac, but the key output is controlled through the cascade transistors. This is implemented as follows: a variable resistor regulates the current that enters the base of the first little powerful transistor, and that through the collector-emitter junction controls the base of the second powerful transistor and already he opens and closes the triac. This implements the principle of very smooth control of huge currents on the load.

Answers to the 4 most FAQ by regulators:

1. What is the tolerance of the output voltage? For factory-made instruments of large firms, the deviation will not exceed + -5%
2. What determines the power of the regulator? The output power directly depends on the power source and on the triac that switches the circuit.
3. What are 0-5 volt regulators for? These devices are most often used to power microcircuits and various circuit boards.
4. Why do you need a household regulator 0-220 volts? They are used to smoothly turn on and off household electrical appliances.

4 Do-it-yourself pH diagrams and connection diagram

Briefly consider each of the schemes, features, advantages.

Scheme 1.

A very simple circuit for connecting and smoothly adjusting the soldering iron. Used to prevent the soldering iron tip from burning and overheating. The scheme uses a powerful triac, which is controlled by a thyristor-variable chain resistor.

Scheme 2.

Scheme based on the use of a phase control chip of the type 1182PM1. It controls the degree of opening triac, which controls the load. They are used to smoothly control the degree of luminosity of incandescent bulbs.

Scheme 3.

The simplest scheme for regulating the incandescence of a soldering iron tip. Made in a very compact design using easily accessible components. One thyristor controls the load, the degree of inclusion of which is regulated by a variable resistor. There is also a diode to protect against reverse voltage. thyristor,

Chinese pH at 220 volts

Nowadays, goods from China have become quite a popular topic, and Chinese voltage regulators are not far behind the general trend. Consider the most popular Chinese models and compare their main characteristics.

There is an opportunity to choose any regulator according to your requirements and needs. On average, one watt of useful power costs less than 20 cents, and this is a very favorable price. But still, it is worth paying attention to the quality of parts and assembly, for goods from China it is still very low.