What is the purpose of a variable frequency drive?

A variable frequency drive (VFD) is a type of motor controller that drives an electric motor by varying the frequency and voltage of its power supply. The VFD also has the capacity to control ramp-up and ramp-down of the motor during start or stop, respectively.

Are VFDs more efficient?

VFDs save energy by enabling electric motors to operate at less than full speed. Reducing motor speed by 25\% decreases energy consumption by nearly 60\% while reducing motor speed by 50\% decreases energy consumption by nearly 90\%. Even with the 2\% to 3\% energy loss in the VFD, the energy savings can be very significant.

What are the applications of variable frequency drive?

They are mostly used in industries for large induction motor (dealing with variable load) whose power rating ranges from few kW to few MW.

What is VFD used for?

A VFD (variable frequency drive) is generally used to control a squirrel cage type motor, where both stator and rotor are of a wound type to create the magnetic flux. Servo drives are used to control permanent magnet motors.

How does variable frequency drive work?

Variable Frequency Drive ( VFD ) is used to Control the the motor by varying the fixed frequency, fixed voltage sine wave power (line power) to a variable frequency, variable output voltage. The Speed of the Motor (Ns) is directly proportional to the Frequency (f) , Since the number of poles of motor is fixed.

What is VFD in HVAC?

An HVAC VFD provides the amount of energy needed to handle the instantaneous load of the heating or cooling system. Without a VFD, the air of an HVAC is system is controlled by throttling an inlet vane or braking an outlet damper.