•  The automatic voltage regulator is used to regulate the voltage. and regulator is designed to automatically maintain a constant voltage level. The fluctuation in the voltage mainly occurs due to the variation in load on the supply system. The variation in voltage damages the equipment of the power system.
• A voltage regulator may be a simple “feed-forward” design or may include negative feedback control loops. It may use an electromechanical mechanism, or electronic components. Depending on the design, it may be used to regulate one or more AC or DC voltages.
• In automobile alternators and central power station generator plants, voltage regulators control the output of the plant. In an electric power distribution system, voltage regulators may be installed at a substation or along distribution lines so that all customers receive steady voltage independent of how much power is drawn from the line.
• It controls the voltage of the system and has the operation of the machine nearer to the steady state stability.
• It divides the reactive load between the alternators operating in parallel.The automatic voltage regulators reduce the overvoltages which occur because of the sudden loss of load on the system.
• It increases the excitation of the system under fault conditions so that the maximum synchronising power exists at the time of clearance of the fault.

The Three phase AVR is made of three identical single phase regulator units providing independent control. The three phase range boasts the same standard features with one of the widest ranges as standard in the industry. A number of options are available, making the three phase range a very comprehensive source of secure, stable power.