What is a variable frequency drive?

In some motor driven systems, the load varies with time.
A Large amount of energy can be saved using a variable frequency drive(VFD).
VFDs belongs to a group of equipment called adjustable speed drives or variable speed drives.
VFD changes the frequency of the supply voltages to vary the operating speed of motors.
Thus continuous process speed control can be achieved.
Motor-driven systems are often designed to handle peak loads that have a safety factor.
Therefore, when the system is operated for a long period at a reduced load, that have a safety factor.
By adjusting motor speed closer matching of motor output to load can be achieved, which results in energy savings.
The speed of standard inductions motor can be controlled by variations of the frequency of the voltage applied to the motor.