Answer / rakesh kumar

mna refers to the axis along which the resultant flux is
0 , which coincides with the geometric neutral axis when no
armature current flows but the flow of armaue current
shifts the 0 flux position or the mna in the direction of
rotation in a generator and opposite to it in a motor ,
ideally the brushes should be along the mna as then it
would be unde the influence of no rotational emf induced
due to earlier pole once the the coil crosses the brush or
undergoes commutation , the shift of brushes has got
nothing to do with the shift of mna that is the mna should
remain at the same position , however for the sparkless
commutation mna shoild be along the brush and hence it
would be good if the mna also gets shifted by 90 .

Answer / shailesh jadon

there is no effect of shifting brushes on the mnp . the mnp
basially depends on the position of poles

Answer / vinit

i am satisfied with mr .rakesh and want to add the.shifting of
mna depends only on armature current(or load current)then how can be decided that mna has sifted by 90?

Answer / sandeep

i expect answer to 90. please justify

Answer / m raviteja

mna also shifted to 90 degrees

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