What is Automatic Voltage Stabilizer?

Automatic Voltage Stabilizer (AVS) is an electrical device that can automatically adjust the output voltage to keep it within a set range. It is mainly used to cope with grid voltage fluctuations and ensure that electrical equipment connected to its output can operate at a stable voltage.

1. Working principle

Voltage detection: The automatic voltage stabilizer has a voltage detection circuit inside, which continuously monitors the input voltage. For example, when the grid voltage changes, this detection circuit can quickly sense the increase or decrease in voltage.

Adjustment mechanism:

Transformer type (a common one): If it is an automatic voltage stabilizer based on the transformer principle, when the voltage change is detected, it will adjust the output voltage by controlling the transformer winding turns ratio. For example, when the input voltage increases, it will reduce the number of turns of the transformer's secondary winding, thereby reducing the output voltage; conversely, when the input voltage decreases, the number of turns of the secondary winding is increased to increase the output voltage.

Electronic regulation type: In an electronic regulation type automatic voltage stabilizer, electronic components such as thyristors (silicon controlled rectifiers) are used to control the voltage. When the input voltage changes, the output voltage is adjusted by changing the conduction angle of the thyristor. For example, by adjusting the triggering time of the thyristor, controlling its conduction degree, the output voltage can be changed.

2. Main components

Voltage detection unit: This is the "eye" of the automatic voltage stabilizer, usually composed of a voltage transformer or a voltage divider resistor, etc., which is used to accurately measure the input voltage.

Control unit: It is like a "brain", which analyzes and judges the signal from the voltage detection unit, and then issues a control instruction. The control unit can be composed of an integrated circuit (IC), a microprocessor or other logic circuits.

Voltage regulation unit: This is the "executor" for achieving voltage stability, which actually adjusts the output voltage according to the instructions of the control unit. As mentioned above, regulating elements such as transformers or thyristors belong to this unit.

Protection unit: In order to prevent the voltage stabilizer itself and the connected equipment from being damaged due to abnormal conditions (such as overvoltage, overcurrent, short circuit, etc.), the protection unit will take measures when these conditions occur, such as cutting off the circuit or issuing an alarm signal. The protection unit may include fuses, overvoltage protectors, overcurrent protectors, etc.

3. Application scenarios

Industrial field: In factories, many precision industrial equipment, such as CNC machine tools, automated production line equipment, electronic instruments, etc., have high requirements for voltage stability. Automatic voltage stabilizers can ensure that these devices can still work normally when the grid voltage fluctuates, avoiding equipment damage or production quality problems caused by unstable voltage.

Commercial field: In shopping malls, supermarkets, office buildings and other places, there are a large number of electrical equipment, such as air-conditioning systems, elevators, computer servers, etc. Automatic voltage stabilizers can provide stable voltage for these devices, extend the service life of the equipment, and reduce the cost of fault repairs caused by voltage problems.

Home field: For some household appliances that are sensitive to voltage, such as computers, televisions, refrigerators, etc., the use of automatic voltage stabilizers can prevent damage to electrical appliances due to excessively high or low voltage. Especially in areas where the grid voltage is unstable, it can effectively protect household appliances.