Types of voltage stabilizers 220v for home, how to choose the best

There are various possibilities for protecting electrical appliances when the parameters of the electric line deviate from the nominal ones. A sinusoidal signal with a value of 220 volts is transmitted along the network line, deviations of this value are permissible within 15 percent and are normally perceived by household appliances. To maintain the voltage value within this limit, the easiest way is to use a voltage stabilizer.

Types and principle of operation of the stabilizer

In retail outlets you can find different type and principle of action voltage stabilizers, in another way they are called normalizers. But despite the diversity, their tasks are the same - to maintain the rated voltage in the supply network. The requirements imposed on them are to provide fast response to signal changes, high values ​​of the coefficient of performance (COP), transmission of the correct sinusoid and the reliability of control of the input and output signals.

Before deciding which voltage regulator to choose, you need to know their differences. Voltage stabilizers are classified according to their principle of operation, they are:

• relay;
• thyristor;
• electromechanical;
• ferroresonant;
• double conversion.

In addition, they are distinguished by their technical characteristics, including the values ​​of the rated power, the range of stabilized voltage, the type of network used.

Relay type device

This is the most popular type of device with a low price tag. The main elements used in relay type devices are:

• relay;
• transformer;
• Control block.

The design is based on the ability of the relay to connect or disconnect, using its contacts, taps from the secondary winding of the transformer. The relays are made in a sealed case, which protects them from dust. Which winding to connect is analyzed by the control unit.

The operation of the device is as follows. The control unit monitors the change in the signal level at the input of the stabilizer and compares it with a reference voltage of 220 volts. When the voltage decreases with the help of a relay, an additional winding of the transformer is connected, adding voltagerequired to compare its level with the reference. When increasing, on the contrary, one of the windings is turned off. Due to this nature of work, the used transformer is called a booster transformer.

The transformer itself works according to the following principle: the mains voltage falls on its primary winding. When a variable current passes through it, an alternating magnetic flux is formed. This flux penetrates the core and all windings in which an electromotive force (EMF) is induced. If a load is connected to the secondary winding, then under the action of the EMF, an alternating current begins to flow through it. In this case, the secondary winding has several branches, made in its different places. To increase the voltage, the number of connected turns increases, and to decrease it decreases.

The number of additional windings depends on the device model and affects the accuracy of the output signal. The more of them, the closer to the value of 220 volts the output value will be. Due to the stepped form of control, when switching the windings, voltage surges occur, while the normal output signal will be a value from 203 to 237 volts.

Benefits this type of stabilizationbesides the price, there is a high ability to withstand overloads and a wide range of operating temperatures from -40 to +40 degrees Celsius. Such normalizers are practically insensitive to the frequency shape of the input signal. The disadvantages include: noise arising when the relay is triggered, low power and reliability. Reliability depends on the quality of the relay. The stepwise method of adjusting the signal leads to short-term surges in the voltage level, which negatively affects the equipment connected to the stabilizer.

Thyristor voltage normalizer

The operation of this type of stabilizer does not differ in its principle of operation from the relay. Only instead of unreliable and noisy relays, a semiconductor element, a thyristor, is used. It is a radioelement with two stable states with three or more pn transitions. In its work, it resembles an electronic key.

Such devices are also called triac, the differences are only in that the thyristor passes the signal in only one direction, and the triac in both directions. Two thyristors connected in parallel and towards each other form a triac. Stabilization occurs by connecting or disconnecting additional windings by opening or closing the thyristor.

Thyristor stabilizers issued as one, and two stages of transformation. In the second case, at the first stage, there is a rough setting of the signal level, and at the second, it is accurate. This allows high accuracy of the output voltage level to be achieved. The benefits include:

• lack of noise;
• high reliability;
• low power consumption;
• high performance;
• small physical dimensions.

In addition, due to the use of microprocessor control, the thyristor stabilizer does not distort the output signal shape.

The disadvantages are the high cost due to the use of expensive thyristors and complex electronic control circuit. And also thyristor normalizers are not devoid of the lack of relay-type stabilization, namely step regulation. For example, with a stabilization accuracy of 2%, the output voltage step is 6 volts.

Servo type normalization

Another name for a servo normalizer is an electromechanical type stabilizer or a servo motor. Such a device consists of three main elements:

• autotransformer;
• electric motor;
• control boards.

The principle of operation lies in smooth movement with the help of a carbon brush motor, closing the secondary windings of the autotransformer. Its windings are interconnected, and due to this, both magnetic and electrical connections arise. The secondary winding of the autotransformer has at least four taps, each of which has its own voltage value.

The operation of the motor is controlled by an electronic board with a microprocessor. Thanks to this approach, voltage stabilization occurs without transient processes and the output waveform does not change. The correct sine wave is important for devices using motors in their design, which overheat when the signal is very noisy.

The disadvantage of servo-motor governors is the low speed of response. For example, if the input signal deviates by 5%, the response time is 0.2 seconds. In addition, such a stabilizer generates increased noise during operation.

Ferroresonance device

This type of normalizer uses in its work ferroresonance effectarising in the transformer-capacitor bundle. That's why it got its name: ferroresonant stabilizer. Structurally, this kind of normalizer is similar to the transformer type. But here the used transformer is not symmetrical, the secondary winding is placed on a magnetic circuit with a large cross-section, which does not allow it to be in a state of saturation.

In such a transformer, three magnetic fluxes of power change arise, the magnitude of which leads to equalization of the output voltage. A capacitor is connected in parallel to the secondary winding and, accordingly, to the load. The addition of a capacitor stabilizes the voltage at low magnetizing currents, increasing the power factor.

The main disadvantage of this type of device is the low power factor. In addition, the stabilizer has a large weight and size, noise during operation. Its advantages are in the accuracy of regulation and high reliability.

Inverter Power Normalizer

The principle of operation is based on double conversionand input signal first into a constant, and then back into a variable. Its indisputable advantage is the use of not bulky 50 Hz transformers at the heart of the design, but a complex of software and hardware implementation. This makes it possible to achieve an efficiency of more than 90% and at the same time provide excellent voltage stabilization accuracy.

The inverter stabilizer includes:

• voltage driver;
• microcontroller;
• capacity;
• rectifier;
• power corrector.

The alternating current, entering the rectifier and passing through the frequency filter, is converted into a constant value. A high-voltage stabilized signal is fed to the inverter, accumulating on the DC bus capacitors. The inverter unit is assembled on a pulse-width modulation (PWM) microcircuit and IGBT power transistors. The PWM controller generates a high-frequency signal, about 20 kHz, which controls the opening of the IGBT transistors. Then, using a capacitive-inductive filter, an alternating output signal is formed.

Due to the application of this approach, the device smoothly regulates the signal and produces a sinusoid of excellent quality, which is important, for example, for the operation of gas boilers. The disadvantage is the use of expensive radio components, which leads to the highest price of all types of stabilizers. IGBT power switches need in overheating protection, so they are installed on coolers, which adds to the noise level.

Choosing a voltage regulator

When choosing a stabilizer to work with a specific device or to use it to supply electricity to a house, the selection criteria remain the same.

Depending on the type of network, a single-phase device is selected for 220 volts, and a three-phase device for 380 volts. An important parameter is the input voltage range, since when this limit is exceeded, the stabilizer will disconnect the load connected to it or turn itself off. To choose it correctly, you need to know the voltage spread in the electrical network. You can find it out by measuring the signal strength at different times of the day over several days.

When choosing a voltage stabilizer for a home, not only the type of devices that need protection is taken into account, but also their peak power. Its value is taken with a margin of at least fifteen percent and is calculated by adding up the power of all devices connected to the stabilizer. Active power is always indicated in watts (W) and full power in volt-amperes (VA). They correlate with each other as 1VA = 0.6 - 0.8 W. It must be understood that motors have starting currents and power stabilization devices when used asynchronous electric motors, compressors, pumps, should be 3-4 times higher than the operating power consumers.

Giving preference to the type of device, it is taken into account that electromechanical models are suitable for protecting high-precision equipment. Relay and thyristor for lines on which significant voltage surges occur, and the requirements for stabilization accuracy are not the main factor. For example, these are electronic components that are sensitive to fluctuations in voltage values, installed in refrigerators, freezers and the like, which have starting motors in their design.

According to statistics, the following manufacturers are among the most popular devices on the market that have earned the trust of buyers:

• APC;
• Luxeon;
• Resant;
• Powercom;
• RUCELF;
• Energy;
• Logicpower.

By purchasing a device from well-known brands, the consumer receives not only compliance with the declared parameters with real characteristics, but also the provision of warranty and post-warranty service support. Almost all voltage stabilization devices are equipped with informative screens that can display: input and stabilized voltage value, power consumption value, waveform, etc. like that.