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                      
Google
   
 
Categories >> Engineering >> Electrical Engineering
 
 


 

 
 Civil Engineering interview questions  Civil Engineering Interview Questions (3011)
 Mechanical Engineering interview questions  Mechanical Engineering Interview Questions (3270)
 Electrical Engineering interview questions  Electrical Engineering Interview Questions (13221)
 Electronics Communications interview questions  Electronics Communications Interview Questions (2348)
 Chemical Engineering interview questions  Chemical Engineering Interview Questions (407)
 Aeronautical Engineering interview questions  Aeronautical Engineering Interview Questions (76)
 Bio Engineering interview questions  Bio Engineering Interview Questions (16)
 Metallurgy interview questions  Metallurgy Interview Questions (79)
 Industrial Engineering interview questions  Industrial Engineering Interview Questions (162)
 Instrumentation interview questions  Instrumentation Interview Questions (2317)
 Automobile Engineering interview questions  Automobile Engineering Interview Questions (104)
 Mechatronics Engineering interview questions  Mechatronics Engineering Interview Questions (38)
 Marine Engineering interview questions  Marine Engineering Interview Questions (43)
 Power Plant Engineering interview questions  Power Plant Engineering Interview Questions (73)
 Engineering AllOther interview questions  Engineering AllOther Interview Questions (1189)
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
 
A FIELD MAGNET IS EXITED BY AC/DC?   4
What is mean by nominal voltage,Explain?.How much nominal voltage?.   1
what purpose of the percentage impendance in transformer   3
What is a liquid resistance starter?where it is used?? Mecon 9
how can u determine size of the conductor by knowing the voltage level   2
what is induction relay   1
Can I use 1 phase power supply to run 3 phase motor? If yes, how?   5
1.type of oil in used in transformer.   7
what is the healthy specific gravity of lead acid battery used in DG sets ? Bhushan-Power-Steel 3
WHY IS THE NO LOAD CURRENT SMALL FOR A TRANSFORMER COMPARED TO OTHER ROTATING ELECTRICAL MACHINES??   1
what is thermo stat, explain how its working?   1
what is rated current and operating current?   1
 
For more Electrical Engineering Interview Questions Click Here 
 
 
 
 
 


   
Copyright Policy  |  Terms of Service  |  Articles  |  Site Map  |  RSS Site Map  |  Contact Us
   
Copyright 2013  ALLInterview.com.  All Rights Reserved.

ALLInterview.com   ::  KalAajKal.com