ALLInterview.com :: Home Page            
 Advertise your Business Here     
Browse  |   Placement Papers  |   Company  |   Code Snippets  |   Certifications  |   Visa Questions
Post Question  |   Post Answer  |   My Panel  |   Search  |   Articles  |   Topics  |   ERRORS new
   Refer this Site  Refer This Site to Your Friends  Site Map  Bookmark this Site  Set it as your HomePage  Contact Us     Login  |  Sign Up                      
tip   To Refer this Site to Your Friends   Click Here
Google
   
 
Categories  >>  Engineering  >>  Electrical Engineering
 
 


 

 
 Civil Engineering interview questions  Civil Engineering Interview Questions
 Mechanical Engineering interview questions  Mechanical Engineering Interview Questions
 Electrical Engineering interview questions  Electrical Engineering Interview Questions
 Electronics Communications interview questions  Electronics Communications Interview Questions
 Chemical Engineering interview questions  Chemical Engineering Interview Questions
 Aeronautical Engineering interview questions  Aeronautical Engineering Interview Questions
 Bio Engineering interview questions  Bio Engineering Interview Questions
 Metallurgy interview questions  Metallurgy Interview Questions
 Industrial Engineering interview questions  Industrial Engineering Interview Questions
 Instrumentation interview questions  Instrumentation Interview Questions
 Automobile Engineering interview questions  Automobile Engineering Interview Questions
 Mechatronics Engineering interview questions  Mechatronics Engineering Interview Questions
 Marine Engineering interview questions  Marine Engineering Interview Questions
 Power Plant Engineering interview questions  Power Plant Engineering Interview Questions
 Engineering AllOther interview questions  Engineering AllOther Interview Questions
Question
how to calculate the KVAr for an motor for improving the PF
 Question Submitted By :: Nellai Sankar
I also faced this Question!!     Rank Answer Posted By  
 
  Re: how to calculate the KVAr for an motor for improving the PF
Answer
# 1
Example:Calculation of the kVAR rating for 1750kW Motor

Motor Data:
Rating of Motor: 1750kW
System voltage: 6.6kV
Power factor of the motor when running at 75% of full
load : 0.84

(Power factor of the motor is considered at 75% of full
load, assuming that the motor will be loaded at an average
of 75%)

Target Power factor : 0.95 lag ( To improve the power
factor from 0.84 to 0.95, after adding the capacitor bank
in the motor circuit)

Required kVAR of the Capacitor Bank to
achieve the target power factor.

KVAr = KW ((TanQ1- TanQ2)

where
Q1= Cosinsverse(P.F1)Initial Power Factor Angle
Q2= Cosinsverse(P.F2)Target Power Factor Angle

So, required kVAR
=0.75*1750*(tan (cos-1 (0.84)) - tan (cos-1 (0.95)))

= 416kVAR
 
Is This Answer Correct ?    61 Yes 10 No
Guest
 
  Re: how to calculate the KVAr for an motor for improving the PF
Answer
# 2
presen load and pf 
Is This Answer Correct ?    5 Yes 2 No
Balamurugan.r
 
 
 
  Re: how to calculate the KVAr for an motor for improving the PF
Answer
# 3
Same as calculated above 
Is This Answer Correct ?    6 Yes 1 No
Ashok Chodankar
 

 
 
 
Other Electrical Engineering Interview Questions
 
  Question Asked @ Answers
 
why CFL lamp requires less electricity than a normal lamp?/  3
why in India it is maintained for exactly 50HZ frequency, why it is not that 49Hz,why it is so?  2
MCB is used for high rating &MCB is used for lower rating.What is technical difference between ACB & MCB?  6
What are effect of radio system in DCS Distributed control system ? Sabic1
what is the difference between cable routing and scheduling? Techno-Labs4
What is the PI test stand for transformer and what is the producer to do this test?  1
what is wave trap? please explain the working and principle  3
There are a Transformer and an induction machine. Those two have the same supply. For which device the load current will be maximum? And why?  4
what is the function of breather in a transformer Bhel26
what is the advantage of Cathodic eathing system and what is the basic principle and how itis working, please explain clearly . Meinhardt2
What is the minimum percentage of power that a powerplant can support in ilanding mode ?  1
define ac reactor? thier application;  1
 
For more Electrical Engineering Interview Questions Click Here 
 
 
 
 
 


   
Copyright Policy  |  Terms of Service  |  Help  |  Site Map 1  |  Articles  |  Site Map  |   Site Map  |  Contact Us interview questions urls   External Links 
   
Copyright © 2012  ALLInterview.com.  All Rights Reserved.

ALLInterview.com   ::  Forum9.com   ::  KalAajKal.com