A salient or project pole type alternator is the one in which projecting poles are mounted on the circular steel frame that is fixed on shaft of alternator.
The EMF generated in a conductor at any instant is mathematically given by:
e = Blv volts
Where in above equation:
- B = instantaneous value of flux density in Wb/m²
- l = length of conductor in metres
- v = speed of conductor in m/s
EMF generated is directly proportional to flux density. (Since I and v are constant)
In case of non-salient or cylinderical pole type alternator rotor, the air gap is of constant length and sine wave is obtained by distributing field winding in several slots.