Answer / coolsunil56

dc excitation is given to rotor so that it gets magnetised and gets locked with magnetic revolving field of statorand start rotating with same speed means at synchronous speed.

Answer / k.sri405

dc can produced flux but it is constant in nature so magnet
have constant pole. that's why this pole gets locked with
the poles of stator

Answer / kundanmalani1990

Excitaion r use to the pole r converte to the parmanet magnet so the excitation r use

Answer / naveen

D.C Supply in alternater  used for genarating magnatic field in roter ,But nature of field would be Stationary Not fluctuating, when Roter get speed from prime mover  its Induced VOLTAGE AND CURRENT in Armature. 

Answer / vamsi

ac alternator is not a salf stator so dc supply for self
motor,dc can not produce flux.

If the Brush of DC motor is shifted by 90 deg, then what happens to voltage and torque? Both voltage and torque are zero. how to justify the answer?

0 Answers  

Why dnt we generate 5-ph or 7-ph supply like as 3-ph supply

2 Answers  

How earth resistance reduses by pouring water coal and salt?

4 Answers  

how bucchos relay works in a transformer

8 Answers   Indeco,

why ct's&pt'S out put called as burden,why compelsary short ckt the secondary of ct's while removing the burden?

0 Answers  

how will you find out the fuse failure by remote operation?

1 Answers  

what happened if power factor is "1"

9 Answers   Reliance,

kVA rating of open delta connected transformer is _____% kVA rating of delta/delta connection A 50 B 70.7 C 57.7 D 75.7

2 Answers  

What is working Priniciple of TVSS ????

1 Answers   Emerson,

If a motor of 30KW rating &200 mtrs distance from feeder give me the cable size selection calculation?

0 Answers  

Why transformer making sound during operations?

2 Answers  

what is busbar. how many types of starter.what appartus will be used to improve voltage.what is the function of starter.what is b.h.p.what material is used for earthing.

1 Answers