Answer / vijay

vvvfd means varieable voltage variable freqwency drive.

Answer / iamdon

The electric drive which uses variable voltage and variable
frequency for its operation and control is called VVVF
drives.With the technology improvement in the realm of
power electronics now it is more easy to work with VVVF.
Cycloconverters are employed to obtain variable frequency
up to 400Hz.

VVVF find applications in railways traction,airplane etc.

Author:arbelectbit@yahoo.com

Answer / shashi bhushan

generaly AC drive supplied with AC voltage , but where we
need variable source , there we use VVVFD(variable voltage
variable frequency drive).
raquirement for VVVFD.......
1.ac source
2.rectfier circuit.
3.filter circuit.
4.inverter circuit
5.IGBT

Answer / kaushal

varible voltage and varible frquency drive

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