In DC motor,the field MMF is given by NI.N-no.of field
winding turns,I-excitation and both are constant.Then how
could the main flux decreases due to armature reaction.

Answer Posted / vivin

This armature reaction has two effects
i)demagnetising the field flux(The direction of the flux
around armature conductors can be inferred from the fleming
RH rule)
i))Distortion of the field flux becoz it is in diferent
direction withrespect to main field flux.

Is This Answer Correct ?    11 Yes 1 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

State kirchoff current law?

662


how can you size an automatic voltage regulator?

1871


What is state space method ? Why its used ? Can it applicable on linear, non-linear, 1st order, higher order, homogeneous, non-homogeneous, open-loop , closed loops , stable & unstable systems ?

1597


Please brief what is sinewave

1731


whatis the commertial spec. of distribution boards ?

1542






The Q-facr o of a coil given as wL/R. what will be shape of Q versus frequency graph.

1557


What are the advantages and disadvantages of the ac motors?

625


please tell me when we start motor without load in star or delta connection whose current above condition,pl write formula

1795


how can get electrical c licence.now i am working in spining mill , transformer capacity 2750KVA. SANCTION DEMAND 2250KVA. PLEASE ADVISE ME . MY CONTACT NO 09944226823

1374


In Dyn11 power transformer if any one of the 3 phases connected to earth in star connected side then please explain effect of the current flow in delta connected side of transformer.(In this case if one phase is shorted to ground in star connected side then we observe the current flow in two phases only not three phases in delta connected primary side. Please explain why it is so?)

1306


when will be the iocl interview results ifaced the interview on september 8 th

1639


What is the de rating factor of cable? What is the importance of the de rating factor in cable selection?

1626


How phase to phase voltage comes 440V.

1457


The Howland current source produces a A Unidirectional floating load current B Bidirectional single-ended load current C Unidirectional single-ended load current D Bidirectional floating load current

1649


I am designing new project sub station with 220 kV / 11 kV, 40 MVA capacity. This project have many recifier sets, which can generate 3rd harmonics. Now I have to select vector group of This transformer. To minimise 3rd harmonics, what care should I take in selection of Transformer Vecrtor group? If it is Y-Y with open Delta tertiary then what should be the rating & voltage of Tertiary Winding?

1455