What is the difference between AC Drive and VFD?

Answer Posted / r. anand

VFD(Variable frequency Drive) is a type of AC Drive.
There are two types of AC Drives of this category,
VVD (Variable Voltage Drive)in which the speed of the drive
can be controlled by varying the voltage input to the drive.
and
VFD (Variable Frequency Drive)in which the speed of the
drive can be controlled by varying the input frequency to
the drive.

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