As the advancement of the conventional relay type voltage stabilizers, modern innovative stabilizers use high performance digital control circuits and solid state control circuitry that eliminates potentiometer adjustments and allows the user to set voltage requirements through a keypad, with output start and stop facility.
This also led to make the trip timing or responsiveness of the stabilizers to a very less rate, typically less than a few milliseconds, in addition this can be adjusted with variable setting. Nowadays, stabilizers have become an optimized power solution to many electronic appliances that are sensitive to voltage fluctuations and they have been found working with many devices such as CNC machines, air conditioners, television sets, medical equipment, computers, telecommunication equipments, and so on.
What is a voltage stabilizer?
It is an electrical appliance which is designed to deliver a constant voltage to a load at its output terminals regardless of the changes in the input or incoming supply voltage. It protects the equipment or machine against over voltage, under voltage, and other voltage surges.
It is also called as automatic voltage regulator (AVR). Voltage stabilizers are preferred for costly and precious electrical equipment to protect them from harmful low/high voltage fluctuations. Some of these equipments are air conditioners, offset printing machines, laboratory equipments, industrial machines, and medical apparatus.
Voltage stabilizers regulate the fluctuating input voltage before it can be fed to the load (or equipment which is sensitive to voltage variations). The output voltage from the stabilizer will stay in the range of 220V or 230V in case of single phase supply and 380V or 400V in case of three phase supply, within given fluctuating range of input voltage. This regulation is carried by buck and boost operations performed by internal circuitry.
There are huge varieties of automatic voltage regulators available in today’s market. These can be single or three-phase units as required by the type of application and capacity (KVA) needed. Three-phase stabilizers come in two versions as balanced load models and unbalanced load models.
These are available either as dedicated units for appliances or as a big stabilizer unit for whole appliances in a particular place, say whole house. In addition, these can be either analog or digital type of stabilizer units.
The common types of voltage stabilizers include manual operated or switchable stabilizers, automatic relay type stabilizers, solid state or static stabilizers, and servo controlled stabilizers. In addition to the stabilizing function, most stabilizers come with additional features such as input/output low voltage cutoff, input/output high voltage cutoff, overload cutoff, output start and stop facility, manual/auto start, voltage cutoff display, zero voltage switching , etc.
Why Voltage Stabilizers Are Needed?
Generally, each and every electrical equipment or device is designed for a wide range of input voltage. Depending on the sensitivity, the working range of the equipments are limited to a specific values, for instance, some equipments can tolerate ± 10 percent of the rated voltage while others ± 5 percent or less.
The voltage fluctuations (rise or dip of the magnitude of rated voltage) are quite common in many areas, especially at terminated lines. The most common reasons for voltage fluctuations are lighting, electrical faults, faulty wiring and periodic turning off the device. These fluctuations create mishap to the electrical equipments or appliances.
How Voltage Stabilizer Works?
Basic Principle of voltage stabilizer to perform Buck and Boost operations
In a voltage stabilizer, voltage correction from over and under voltage conditions is performed through two essential operations, namely boost and buck operations. These operations can be carried manually by switches or automatically through electronic circuitry. During under voltage condition, boost operation increases the voltage to a rated level while buck operation reduces the voltage level during over voltage condition.
The concept of stabilization involves adding or subtracting the voltage to and from the mains supply. For performing such task stabilizer uses a transformer which is connected in different configurations with switching relays. Some stabilizers use a transformer with taps on winding to provide different voltage corrections while servo stabilizers use an auto transformer to have a wide range of correction.
The figure above illustrates the boosting configuration in which the polarity of the secondary winding is oriented in such a way that its voltage is directly added to the primary voltage. Therefore, in case of under voltage condition, transformer (whether it can be tap changing or autotransformer) is switched by the relays or solid state switches such that additional volts are appended to the input voltage.
In the figure above, transformer is connected in bucking configuration, wherein the polarity of secondary coil is oriented in such a way that its voltage subtracts from the primary voltage. The switching circuit shifts the connection to the load to this configuration during over voltage condition.
The figure above shows two stage voltage stabilizer which uses two relays to provide constant AC supply to the load during overvoltage and under voltage conditions. By switching the relays, buck and boost operations for two specific voltage fluctuations (one is under voltage, for instance, say 195V and another for overvoltage, say 245V) can be performed.
In case of tapping transformer type stabilizers, different taps are switched based on the required amount of boost or buck voltages. But, in the case of auto transformer type stabilizers, motors (servo motor) are used along with sliding contact to obtain boost or buck voltages from the auto transformer as it contains only one winding.
Types of Voltage
Voltage stabilizers have become an integral part of many electrical appliances of home, industries and commercial systems. Earlier, manually operated or switchable voltage stabilizers were used to boost or buck incoming voltage in order to give an output voltage within a desired range. Such stabilizers are built with electromechanical relays as switching devices.
Later, additional electronic circuitry automates the process of stabilization and gave birth to tap changer automatic voltage regulators. Another popular type of voltage stabilizer is servo stabilizer in which voltage correction is carried continuously without any switch. Let us discuss three main types of voltage stabilizers.
Relay Type Voltage Stabilizers
In this type of voltage stabilizers, voltage regulation is accomplished by switching the relays so as to connect one of a number of tappings of the transformer to the load (as in the manner discussed above) whether it is for boosting or bucking operation. The figure below illustrates the internal circuitry of relay type stabilizer.
It has electronic circuit and set of relays besides the transformer (which can be toroidal or iron core transformer with tappings provided on its secondary). The electronic circuit comprises rectifier circuit, operational amplifier, microcontroller unit, and other tiny components.
As the advancement of the conventional relay type voltage stabilizers, modern innovative stabilizers use high performance digital control circuits and solid state control circuitry that eliminates potentiometer adjustments and allows the user to set voltage requirements through a keypad, with output start and stop facility.
This also led to make the trip timing or responsiveness of the stabilizers to a very less rate, typically less than a few milliseconds, in addition this can be adjusted with variable setting. Nowadays, stabilizers have become an optimized power solution to many electronic appliances that are sensitive to voltage fluctuations and they have been found working with many devices such as CNC machines, air conditioners, television sets, medical equipment, computers, telecommunication equipments, and so on.
What is a voltage stabilizer?
It is an electrical appliance which is designed to deliver a constant voltage to a load at its output terminals regardless of the changes in the input or incoming supply voltage. It protects the equipment or machine against over voltage, under voltage, and other voltage surges.
It is also called as automatic voltage regulator (AVR). Voltage stabilizers are preferred for costly and precious electrical equipment to protect them from harmful low/high voltage fluctuations. Some of these equipments are air conditioners, offset printing machines, laboratory equipments, industrial machines, and medical apparatus.
Voltage stabilizers regulate the fluctuating input voltage before it can be fed to the load (or equipment which is sensitive to voltage variations). The output voltage from the stabilizer will stay in the range of 220V or 230V in case of single phase supply and 380V or 400V in case of three phase supply, within given fluctuating range of input voltage. This regulation is carried by buck and boost operations performed by internal circuitry.
There are huge varieties of automatic voltage regulators available in today’s market. These can be single or three-phase units as required by the type of application and capacity (KVA) needed. Three-phase stabilizers come in two versions as balanced load models and unbalanced load models.
These are available either as dedicated units for appliances or as a big stabilizer unit for whole appliances in a particular place, say whole house. In addition, these can be either analog or digital type of stabilizer units.
The common types of voltage stabilizers include manual operated or switchable stabilizers, automatic relay type stabilizers, solid state or static stabilizers, and servo controlled stabilizers. In addition to the stabilizing function, most stabilizers come with additional features such as input/output low voltage cutoff, input/output high voltage cutoff, overload cutoff, output start and stop facility, manual/auto start, voltage cutoff display, zero voltage switching , etc.
Why Voltage Stabilizers Are Needed?
Generally, each and every electrical equipment or device is designed for a wide range of input voltage. Depending on the sensitivity, the working range of the equipments are limited to a specific values, for instance, some equipments can tolerate ± 10 percent of the rated voltage while others ± 5 percent or less.
The voltage fluctuations (rise or dip of the magnitude of rated voltage) are quite common in many areas, especially at terminated lines. The most common reasons for voltage fluctuations are lighting, electrical faults, faulty wiring and periodic turning off the device. These fluctuations create mishap to the electrical equipments or appliances.
How Voltage Stabilizer Works?
Basic Principle of voltage stabilizer to perform Buck and Boost operations
In a voltage stabilizer, voltage correction from over and under voltage conditions is performed through two essential operations, namely boost and buck operations. These operations can be carried manually by switches or automatically through electronic circuitry. During under voltage condition, boost operation increases the voltage to a rated level while buck operation reduces the voltage level during over voltage condition.
The concept of stabilization involves adding or subtracting the voltage to and from the mains supply. For performing such task stabilizer uses a transformer which is connected in different configurations with switching relays. Some stabilizers use a transformer with taps on winding to provide different voltage corrections while servo stabilizers use an auto transformer to have a wide range of correction.
The figure above illustrates the boosting configuration in which the polarity of the secondary winding is oriented in such a way that its voltage is directly added to the primary voltage. Therefore, in case of under voltage condition, transformer (whether it can be tap changing or autotransformer) is switched by the relays or solid state switches such that additional volts are appended to the input voltage.
In the figure above, transformer is connected in bucking configuration, wherein the polarity of secondary coil is oriented in such a way that its voltage subtracts from the primary voltage. The switching circuit shifts the connection to the load to this configuration during over voltage condition.
The figure above shows two stage voltage stabilizer which uses two relays to provide constant AC supply to the load during overvoltage and under voltage conditions. By switching the relays, buck and boost operations for two specific voltage fluctuations (one is under voltage, for instance, say 195V and another for overvoltage, say 245V) can be performed.
In case of tapping transformer type stabilizers, different taps are switched based on the required amount of boost or buck voltages. But, in the case of auto transformer type stabilizers, motors (servo motor) are used along with sliding contact to obtain boost or buck voltages from the auto transformer as it contains only one winding.
Types of Voltage
Voltage stabilizers have become an integral part of many electrical appliances of home, industries and commercial systems. Earlier, manually operated or switchable voltage stabilizers were used to boost or buck incoming voltage in order to give an output voltage within a desired range. Such stabilizers are built with electromechanical relays as switching devices.
Later, additional electronic circuitry automates the process of stabilization and gave birth to tap changer automatic voltage regulators. Another popular type of voltage stabilizer is servo stabilizer in which voltage correction is carried continuously without any switch. Let us discuss three main types of voltage stabilizers.
Relay Type Voltage Stabilizers
In this type of voltage stabilizers, voltage regulation is accomplished by switching the relays so as to connect one of a number of tappings of the transformer to the load (as in the manner discussed above) whether it is for boosting or bucking operation. The figure below illustrates the internal circuitry of relay type stabilizer.
It has electronic circuit and set of relays besides the transformer (which can be toroidal or iron core transformer with tappings provided on its secondary). The electronic circuit comprises rectifier circuit, operational amplifier, microcontroller unit, and other tiny components.
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