Answer / haider imam

vvvf is genaraly use in ac drive because only change
frequancy in ac drive in dc drive there is no any
ferequancy so how regulate this.

Answer / j.kesavan

A THYRISITOR DRIVE ,ITS VARING THE VOLTAGE AND FREEQUANCY
IN AC, DC DRIVES.

Answer / ismail

VVVF MEANS VARIBLE VOLTAGE AND VERIBLE FRIQUENCY IT TAKE DC
VOLTAGE TO RUN DAT VOLTAGE IS MAY BE 24V DC CORRENT ONLY
DEPENDING UPON THE APPLICATION IT IS BASED

why earthing is not required on transformer prymary winding side ???

13 Answers   Genpact,

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i need to connect fact device(any one from following upsc,sssc,svc,statcom and tcsc)in 14 bus system....by using MATLAB psat software....if i connect these fact devices,i will get some error as "virtual error"...i cnt rectify this error.if anybody know that how to work in psat,pls help me to rectify this error.... or send mail me to, viki0607@yahoo.co.in

1 Answers  

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what are the problems are there if power factor is leading

3 Answers   NTPC,

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previous year paper of ntpc bhel for degree in electrical enng

0 Answers  

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In VSD (variable speed drive)I/P and O/P connections given wrongly what will happen?

5 Answers  

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Why an ac solenoid valve attract the plunger even though we interchanges the terminal? Will the poles changes?

0 Answers  

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What is the difference between earthing,ground&nutral?

2 Answers   Bhel,

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if voltage is not builed up in small generator what will be the reason?

7 Answers   century,

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what is Harmonic effect?

2 Answers  

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for which possible reasons a motor can fail to start??

4 Answers   CEB, Essar,

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What is fuction of NGT/NGR using in Generator.

9 Answers  

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what will happen if a 3 phase motor is connected to a single phase circuit and vice versa?

3 Answers  

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