How VFD (variable frequency drive) works?
What's its function?

Answer Posted / surinder kumar

Hi Below is small write-up in answer of your query

A Variable Frequency Drive (sometimes abbreviated VFD) is
system for controlling the rotational speed of an
alternating current (AC) electric motor by controlling the
frequency of the electrical power supplied to the motor. A
variable frequency drive is a specific type of adjustable
speed drive. Variable frequency drives are also known as
adjustable frequency drives (AFD), variable speed drives
(VSD), AC drives or inverter drives.

Variable frequency drives operates under the principle that
the synchronous speed of an AC motor is determined by the
frequency of the AC supply and the number of poles in
the stator winding, according to the relation:

RPM = 120*f/P

where
RPM = Revolutions per minute
f = AC power frequency (Hertz)
P = Number of poles (an even number)
Synchronous motors operate at the synchronous speed
determined by the above equation.The speed of an induction
motor is slightly less than the synchronous speed.The motor
used in a VFD system is usually a three-phase induction
motor.Variable frequency drive controllers are solid state
electronic power conversion devices.

The usual design first converts AC input power to DC
intermediate power using a rectifier bridge. The DC
intermediate power is then converted to quasi-sinusoidal AC
power using an inverter switching circuit. The rectifier is
usually a three-phase diode bridge, but controlled
rectifier circuits are also used. Low power models are often
configured for use with single-phase input power.

Is This Answer Correct ?    33 Yes 3 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

Define various modes of operation of timer.

593


what is mean of area?

1554


What is meant by filter?

616


what is difference between controlnet,devicenet protocol?

2070


what must be the kind of test on innovatronix

2569






Explain the different modes of buck boost converter

594


Define what is the significance of the arrow-head in the transistor symbol?

803


Define what are the main purposes for which a cc amplifier may be used.

611


Hi, I am an Telceom engineer,I know about LSL,HSL links between various Network Elements. Can anyone explain me about F link in telceom. Regards, Sanchit Bhardwaj

3593


What do you understand by reverse saturation current of a diode?

544


Define angle and amplitude modulation? What is noise in modulation?

641


whatis the test condition for the leakage current rating for 25kv high voltage test on PVC armoured cable?

1388


What is the function of Bias Tee (BPxx) input Which power supply card required for Ultra BTS for DC 24V input What is the state if the GREEN LED is glowing on PWSx card

1964


i want do telecom protocol development course from hyderbad convergence training school so what is the scope after doing that course and will i get a good job after doing the course and what will be the minimum package

1439


can we calculate the voltage level for microwave energy which is using for our mobile communication?

2327