the expression is the same of both condition of operation.

Let Î¦ = useful flux per pole in webers

P = total number of poles
z = total number of conductors in the armature

*n*= Speed of rotation of armature in revolution per second

A = number of parallel path through the armature between the brushes of opposite polarity

Z/A = number of armature conductor in series for each parallel path

Since the flux per pole is Î¦ , each conductor cuts a flux PÎ¦ in one revolution.

Generated voltage per conductor

Since n revolution are made in one second, one revolution will be made in 1/n second. therefore the time for one revolution of the armature is 1/n second.

The average value of generated voltage per conductor

Generated voltage voltage

*E*is determined by the number of armature conductors in series in any one path between the brushes. therefore , total voltage generated*E*= (average voltage per conductor) x (number of conductors in series per path)

E =

*n*PÎ¦ x Z/A**Equation is called the e.m.f. equation of d.c. machine.**

Good

ReplyDeleteads

ReplyDeleteGood job

ReplyDelete## Post a comment