What is a voltage stabilizer? Useful information about stabilizers. What is the difference between a voltage stabilizer and a voltage regulator

Stable voltage will not harm equipment

Every year during winter and summer, our power grid begins to work intermittently, even if it is not felt. In winter - during the period of active use of electrical appliances and means for additional heating. In summer - during the period of rains and thunderstorms. During such periods, power surges regularly occur. Despite the fact that the voltage in our outlets should be 220 volts and the frequency should be 50 Hz, the real situation does not always correspond to the norm. A stable voltage directly determines how long your electrical appliances will last you. This is why voltage stabilizers are extremely popular. They are electronic-mechanical devices that convert electrical energy, so that the output meets all standards. However, it is not enough to just go and buy a stabilizer; you must first decide on the choice of a suitable device. In this article we will talk about what parameters to pay attention to.

Is your voltage stable?

It is very easy to determine whether the voltage in the room is stable. It is enough to notice how often the lamp in your lamp blinks. If the blinking is almost impossible to notice, then everything is in order. If it is present, then it’s time to think about a stabilizer. You can also check the voltage in the outlet yourself using a multimeter. If the voltage surges too sharply, 70-80% of the equipment may fail. Despite the fact that in many modern devices There are built-in fuses, they cannot cope with such a load.

Photo: www.stabilizator-iek.ru

Main selection criteria

Voltage value

First, you must decide for how many devices the voltage stabilizer will work. Will it be, for example, one gas heating boiler or an entire country house. It is important to find out what voltage values ​​your network has, its nominal and maximum.

The most popular is a single-phase (220 V) stabilizer - it is usually used in city apartments. There are also three-phase (380 V) devices - they are used in production shops and are designed for heavy loads. But if the stabilizer is planned to be installed in a country house, then the network can be either single-phase or three-phase. There are several ways to determine this.

• If you lived in a wire going to apartment two or three; if the electricity meter has one blinking LED; if the automatic switch in the electrical panel is one- or two-key, you are using a single-phase network.
• If there were at least four lives in the wire; if there are three blinking LEDs on the meter; if the automatic switch in the panel is three- or four-key, you have access to a two-phase network.

Types of voltage stabilizers

There are several types of stabilizers. The complexity of production of the device and its final cost depend on the type.

• Relay stabilizer. Today, it is the most popular type in the Russian Federation, despite its low price. Can be classified as automatic transformer stabilizers. Thanks to electromechanical power relays, by stepwise regulation of the network, it switches the winding of the autotransformer. An increase or decrease in the output voltage in such a device occurs synchronously with the input voltage. One of the main merits of such a device is the high rate of voltage stabilization (about 20 ms).
• Step voltage stabilizer almost similar to relay. In it, the transformer transition occurs using thyristors and triacs. This is precisely why devices of this type are covered by a long warranty from manufacturers - up to 10 years. This is also facilitated by the absence of mechanical parts and, accordingly, wear.
• Electromechanical stabilizer is a voltage boost transformer. Adjustment takes place using a rotating brush contact. The parameters of the brush assembly determine specifications devices - such as processing speed, dips and surges in voltage. Single-phase electromechanical stabilizers for the home are, as a rule, a single-brush unit with a power of three thousand volt-amperes. Stabilizers made of two brushes are not very popular due to their high cost. Periodically, the brushes will have to be changed, and at the same time the transformer itself will have to be cleaned, but this is not very difficult to do at home. At a relatively low cost, electromechanical devices show high stabilization accuracy and smooth voltage regulation. It is acceptable to use in conditions where the voltage changes periodically and unilaterally. Ideal for connecting to personal computers, household, office equipment. Such stabilizers cannot be connected to welding machines, since their design does not allow them to respond to extremely fast surges in the power supply. The price/quality ratio is the best.
• Considered more reliable electrodynamic stabilizers- one of the varieties of electromechanical. Instead of brushes, rollers are built into them, due to which their wear is almost eliminated. However, along with reliability, the price has also increased.
• Relatively recently, another type of stabilizer was introduced - hybrid or, as it is also called, combined. The difference is that in addition to the electromechanics, a relay part is added. It begins its work when the voltage in the network drops or rises to abnormal values. For example, if the network voltage “floats” in the range from 144 to 256 V, then the hybrid stabilizer works similarly to an electromechanical one. But as soon as the voltage goes beyond these values ​​within 105-280 V, the hybrid device returns it to normal condition with an error of ±10%.
• Double conversion stabilizers- quite expensive devices, but they have a number of very attractive features. Such stabilizers must be used in conjunction with highly sensitive devices whose power ranges from 1 to 30 kW. Possess fast connection, they make almost no noise during operation. They have a wide output voltage range and minimal error. The operation of such a device depends on the existing load on the electrical equipment. The lower voltage range increases from 118 V to 160 V when electrical loads rise by 50% or 70%, respectively.
• A new line in the list of stabilizers are devices with pulse width modulation. The principle of their operation is to regulate the voltage by the above-mentioned modulation. That is, analog filters located at the network input and output of the device stably equalize all interference in the network. Very fast, adjustment accuracy is not lower than 99%. This stabilizer helps with strong power surges, for example, during welding work. Typically, such devices have small size and minimum weight. This is explained by the fact that they do not contain heavy and large transformers. But their price is not small. There are some drawbacks - the upper threshold at the stabilizer input does not exceed 245 V.
• Electromagnetic voltage stabilizer- this is the one whose output voltage is regulated by regulating magnetic fluxes. Magnetization occurs due to a semiconductor regulator. This type has many disadvantages - such as hum during operation, a narrow range of input voltage, high sensitivity when switching to mains frequencies of 50 Hz.

Photo: electro.lg.ua

What you need to know

Almost the first thing you need to decide is the type of stabilizer connection. You can connect it directly to the network at the electrical panel in order to protect all equipment. Or it is possible to permanently connect home appliances directly to the stabilizer - the device is simply connected to an outlet.

If you have a three-phase network, but all devices are single-phase, then you need to take three single-phase converters. But if such a network has at least one three-phase device, then the converter should only be three-phase. This rule is relevant for stabilizing all electrical appliances in the house, and not individually for one.

When choosing a stabilizer, you must imagine what the total power of your devices will be connected to it; the power of your device will come from this parameter. Add 20-30% to the output value to prevent abnormal overload.

To make it easier for you to determine what the total power of your devices is, you can use our table with approximate values.

To clarify the power, please refer to the instructions for your equipment.

The most popular manufacturers

Today there are more than a dozen Russian and foreign companies that successfully produce voltage stabilizers. Each product differs in design, performance, power type and stabilization method. Each company has products with similar parameters. But only when using them in practice do we learn about both the pros and, unfortunately, the cons. Some companies have already lost their quota of trust, but the rest, thanks to quality products, are trying to maintain their brand.

Here are the manufacturers that are popular among consumers in our country:

Russian brands - Polygon, Norma M, Stabvolt, Cascade;

Chinese brands: Solby, Fnex, Sassin, Voltron, Voto;

Western brands: Ortea, Orion.

Foreign brands, although of higher quality, are inferior in terms of demand to Chinese and Russian products. The reason for the dislike of Russian consumers lies in prices. If the domestic product is quite good and much cheaper, then why overpay?

Photo: www.elvs.su

Common Buyer Mistakes

• If the voltage in your house is good, then there is no point in buying a stabilizer for the whole house. It is enough to buy a small device, connecting only very sensitive devices to it.
• In order not to make a mistake when buying a voltage stabilizer, you need to know all the criteria for choosing a device. By approaching this issue responsibly, you will not regret the choice you made.
• Consult a specialist or electrical technician for advice. Installation of certain types of voltage stabilizers requires professional supervision.

The most important parameters of the stabilizer are the stabilization coefficient Kst, output resistance Rout and efficiency η.

Stabilization coefficient determined from the expression K st = [∆u in / u in] / [∆u out / u out]

Where u in, u out- constants at the input and output of the stabilizer, respectively; ∆uin- change u in; ∆uout- change u out, corresponding to the change in ∆u input.

Thus, stabilization coefficient is the ratio of the relative change at the input to the corresponding relative change at the output of the stabilizer.

The greater the stabilization coefficient, the less the output changes when the input changes. For the simplest stabilizers, the value of Kst is units, while for more complex ones it is hundreds and thousands.

Stabilizer output resistance is determined by the expression Rout = | ∆u out / ∆i out |

where ∆uout is the change in the constant at the output of the stabilizer; ∆iout - change in the constant output current of the stabilizer, which caused a change in the output voltage.

The output resistance of the stabilizer is a value similar to the output resistance of a rectifier with a filter. The lower the output resistance, the less the output changes when the load current changes. For the simplest stabilizers, the value of R out is units of Ohm, and for more advanced ones, it is hundredths and thousandths of an Ohm. It should be noted that the stabilizer usually sharply reduces voltage ripple.

The efficiency of the stabilizer η st is the ratio of the power supplied to the load P n to the power consumed from the input source R in: η st = R n / R in

Traditionally, stabilizers are divided into parametric and compensation.

Interesting video about voltage stabilizers:

Parametric stabilizers

They are the simplest devices in which small changes in the output are achieved through the use of electronic devices with two terminals, characterized by a pronounced nonlinearity of the current-voltage characteristic. Let's consider the circuit of a parametric stabilizer based on a zener diode (Fig. 2.82).

Let's analyze this circuit (Fig. 2.82, a), for which we first transform it using the equivalent generator theorem (Fig. 2.82, b). Let's analyze graphically the operation of the circuit by plotting load lines on the current-voltage characteristic of the zener diode for different values ​​of the equivalent voltage corresponding to different values ​​of the input (Fig. 2.82, c).
From the graphical constructions it is obvious that with a significant change in the equivalent u e (by ∆u e), and therefore the input u in, the output changes by an insignificant amount ∆u out.

Moreover, the lower the differential resistance of the zener diode (i.e., the more horizontal the zener diode characteristic is), the less ∆u out.

Let's determine the main parameters of such a stabilizer, for which in the original circuit we replace the zener diode with an equivalent circuit and introduce into the input circuit (Fig. 2.82, d) a voltage source corresponding to a change in the input ∆u input (dotted line in the diagram): R out = r d || R 0 ≈ r d, because R 0 >> r d η st = (u out · I n) / (u in · I in) = (u out · I n) / [ u in (I n + I in) ].

K st = (∆u in / u in) : (∆u out / u out) Since usually R n >> r d Therefore, K st ≈ u out / u in · [ (r d + R 0) / r d ]

Typically, parametric stabilizers are used for loads from several units to tens of milliamps. They are most often used as reference sources in compensation voltage stabilizers.

Compensating stabilizers

They are closed automatic control systems. The characteristic elements of a compensating stabilizer are a reference (reference) source (RS), a comparing and amplifying element (CAE) and a regulating element (RE).

It is useful to note that the OOS covers two stages - on the operational amplifier and on the transistor. The scheme under consideration is a convincing example demonstrating the advantage of the general negative feedback compared to the local one.

The main disadvantage of stabilizers with continuous regulation efficiency is low, since a significant power consumption occurs in the regulating element, since the entire load passes through it, and the drop across it is equal to the difference between the input and output voltages of the stabilizer.

At the end of the 60s, integrated circuits for compensating stabilizers with continuous regulation began to be produced (K142EN series). This series includes stabilizers with a fixed output voltage, with an adjustable output voltage and bipolar and input and output voltages. In cases where it is necessary to pass a current through the load that exceeds the maximum permissible values ​​of integrated stabilizers, the microcircuit is supplemented with external control transistors.

Some parameters of integral stabilizers are given in table. 2.1, and the connection option to the K142EN1 stabilizer external elements- in Fig. 2.85.


Resistor R is designed to trigger current protection, and R 1 is to regulate the output voltage. Microcircuits K142UN5, EH6, EH8 are functionally complete stabilizers with a fixed output voltage, but do not require connecting external elements.

Switching stabilizers are now no less widespread than continuous stabilizers.

Thanks to the use of the key operating mode of the power elements of such stabilizers, even with a significant difference in the levels of input and output voltages you can get an efficiency of 70 - 80%, while for continuous stabilizers it is 30 - 50%.

In a power element operating in switching mode, the average power dissipated in it over the switching period is significantly less than in a continuous stabilizer, since although in the closed state the current flowing through the power element is maximum, the drop across it is close to zero, and in the open state the current flowing through it is zero, although maximum. Thus, in both cases the power dissipation is negligible and close to zero.

Small losses in power elements lead to a reduction or even elimination of cooling radiators, which significantly reduces weight and size indicators. In addition, the use pulse stabilizer allows in some cases to exclude from the scheme power transformer, operating at a frequency of 50 Hz, which also improves the performance of stabilizers.

The disadvantages of switching power supplies include presence of output voltage ripple.

Consider a switching series regulator

Key S is periodically turned on and off by the control circuit (CS) depending on the value on the load. the output is adjusted by changing the ratio t on / t off, where t on, t off - the duration of the time periods during which the key is in the on and off states, respectively. The greater this ratio, the greater the output.

A bipolar or field-effect transistor is often used as a switch S.

The diode ensures the flow of inductor current when the switch is turned off and, therefore, eliminates the appearance of dangerous surges on the key at the time of switching. An LC filter reduces output ripple.

Another interesting video about stabilizers:

There is probably not a single person in our country who has not, in one way or another, experienced power outages. And if the blinking of light bulbs can still be somehow survived, then the failure of the same TV, washing machine or computer will be a significant blow to the budget. Moreover, almost all modern Appliances imported, and they may be vulnerable to the quality of electricity that exists in our country, where voltage surges in the range of up to 10% are considered quite normal.

Most people have a reasonable question: how can we change the current situation and protect ourselves from these risks? The answer is simple - you need to purchase voltages based on the power of those electrical appliances that will be connected to the network in a city apartment. However, here the next question arises - how to choose a voltage stabilizer so that this purchase is not a waste of money? To figure this out, It is necessary to consider all types of these devices, their main advantages and disadvantages.