why the field winding of synchronous machine is excited by dc source

2 Answers  

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what is the difference b/w bus reactor and line reactor?

1 Answers  

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what is the difference between arc and spark

2 Answers   ABB, Jindal,

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Is earthing done for AC or DC or both?

6 Answers  

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In alternator generally we give DC voltage to field of alternator but field (excitor)produce Ac & converts into DC by rotating rectifier(RR ) then fed to rotor .my question is why we cannot give dc voltage directly to rotor instead of Excitor & RR ?

1 Answers  

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hai every bodi please let me know the test procedure for lightning arresters.

2 Answers  

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what is phase shifting transformer.

2 Answers  

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howmuch current can carry the 2.5Sqmm copper cable?

42 Answers  

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What is domestic transformer? Draw the connection of domestic transformer.

0 Answers  

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how the testing of protection CT Testing done through Primary injection kit please describe in detail procedure...

0 Answers  

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can you tell me/show me, how to manually synchronize 2 DG. preferred with video.

2 Answers   Cummins,

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What is the Operating Powerfactor of UPS??? Why??

3 Answers  

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