Answer / karthik

IGBT is nothing but a switch,we can use even MOSFET instead
of IGBT.but the thing is that,IGBT has faster switching
speed,otherwise called the operating frequency,hence the
performance and efficiency of the UPS system gets improved

Answer / ramesh

Good

Answer / dipankar ghorai

To increase the operating frequency of the UPS we may use
it.

Answer / ramesh

High switching speed with high impedance in a single component with low expensive inside of BJT & MOSFET.
    High-current and high-voltage bipolars are available, but their switching speeds are slow, while power MOSFETs may have high switching speeds, but high-voltage and high-current devices are expensive and hard to achieve.so this difficulty shortouted by IGBT

Answer / anil kumar

It also has excellent forward & reverse blocking capabilities.

why the excitation is necessary to produce the reactive power

2 Answers  

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How to calculate CT ratio for 11KV 1500KVA Transformer 500KVA MD and 1400KVA connected load ? Note:- As per MSEB(Maharastra state electricity Board)

1 Answers  

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why do we carry out winding resistance test?

0 Answers   MahaGenco, MAHINDRA,

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Why 3 over-current and 1 earth fault relay is used on primary side of transformer? Why 2 over-current and 1 earth fault relay in used on secondary side of transformer?

1 Answers   Adani,

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difference between relay and solenoid?

2 Answers  

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what should be the acceptrd value of winding resistance for 2.5MVA transformer

0 Answers  

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can anyone pls expain me about how can we design a cable tray??suppose if have to draw a 3 nos of 50 sqmm AYFY and 2 nos of 35 SQmm of AYFY cable through the tray..how can we design the tray size?? regards...

3 Answers  

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What is the reason behind current flow(20 A) in amain earth cable of an SMDB? Is cuurent flow(45A etc) through a neutral cable acceptable?

0 Answers  

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iam interesting to design the control panel for 3 phase pump motors by controling single phase switches.iam plan to use fuse,contactor & relay for motor protection .how can i select the voltage & amps rating for fuse,contactor & relay plz guide me .if anybody clarify my doubt means it will more helpful for my future .

1 Answers  

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when the Transmission and Distribution network where is the "feeder" lines are located? and why should be used in T&D network.....

0 Answers  

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BRIEFELY EXPLAIN MEGGAR PRINCIPLE

2 Answers  

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What is Magnetic Current Test of Transformer.

2 Answers  

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