Answer / waheed imran virk

1) Phase Converter =
Three phase induction motors may operate adequately on an
unbalanced supply if not heavily loaded. This allows
various imperfect techniques to be used. A single-phase
motor can drive a three-phase generator, which will produce
a high-quality three-phase source but with high cost for
apparatus. Several methods exist to run three-phase motors
from a single-phase supply, these can in general be
classified as:
2)VFD =
A variable-frequency drive (VFD) (also termed adjustable-
frequency drive, variable-speed drive, AC drive, micro
drive or inverter drive) is a type of adjustable-speed
drive used in electro-mechanical drive systems to control
AC motor speed and torque by varying motor input frequency
and voltage
While VFDs are used in applications ranging from small
appliances to the largest of mine mill drives and
compressors, about a third of the world's electrical energy
is consumed by electric motors in fixed-speed centrifugal
pump, fan and compressor applications and VFDs' global
market penetration for all applications is still relatively
small. This highlights especially significant energy
efficiency improvement opportunities for retrofitted and
new VFD installations.

advantages of vvvf drives over non vvvf drives for EOT cranes

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draw 3 phase rectifier diagram

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what is dc system? how getting pulse from rectifier?

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Why mostly the HV side of transformer has Delta?

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4 Answers  

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