Home Electrical Power System What is the Function of AVR (Automatic Voltage Regulator)?

What is the Function of AVR (Automatic Voltage Regulator)?


Do you know What is the function of AVR? Can’t concentrate on studying? Sometimes you feel active and sometimes the energy is gone. The cause is a lack of concentration.

If a motivator motivates you in this condition and boosts you up it would be great. And when alternator voltage loses motivation like you, automatic voltage regulator helps the voltage to calm down. It is used for controlling voltage automatically. It takes unstable voltage and makes it stable. Today we will discuss what is the function of AVR?

what is the function of AVR
Lack of Concentration

The Reason Behind The Up-Down of Voltage

Up-down happens for the change of load in the supply system.

Unstable voltage is harmful to devices of the power systems. Destabilized voltage can be prevented by installing a voltage control system in the transformer, generator, feeder, etc. That’s why a voltage control power system has many points for controlling voltage.

In the DC supply system, the compound generator is used for controlling voltage for feeders of the same length. For different lengths, a feeder booster is used to stabilize the voltage.

Amplified signal controls main or pilot exciter’s excitation by a buck or boost action. Exciters output control is taken to the main alternator terminal. 

Suppose, you lost energy while working. Then you have a cup of Horlicks and boost up your energy and the energy is stored in your body. Now we can relate the Horlicks with amplifier and your body with the alternator. 

Principles of Automatic Voltage Regulator / What is the function of AVR?

automatic voltage regulator circuit
Automatic Voltage Regulator Circuit

It works to detect faults. The output voltage of an AC generator is sent to a potential transformer and solved, filtered, and compared to a reference. The difference between the actual voltage and the reference voltage is fault voltage. The fault voltage is amplified by an amplifier. Then it is sent to the main exciter or pilot exciter.

And in this way, the amplified signal controls the excitation of the main or pilot exciter by a buck or boost action.

Practical Use of Automatic Voltage Regulator

Uses of Automatic Voltage Regulator 

  • It controls the voltage of the system and directs the machine with a stable voltage. 
  • It can separate reactive loads of the generators with parallel connections. 
  • An automatic voltage regulator reduces overvoltage which is caused by a change in load.
  • It increases the excitation of system while it is faulty and prevents problems in synchronization.
  • If the system load is changed, then there maybe problem in generator’s excitation. As a result, there is disruption of voltage up-down and alternator synchronization. In this situation to keep the alternator stable, there is no other option.

That’s all for today’s topic what is the function of AVR?

Hope it was helpful for you to understand what is the function of AVR?

You can also read: Why Capacitor is Used in Ceiling Fan?