Specifications
50
Mush winding
In drawing this winding, the slots are numbered from 1 to 24 and the long and short sides
are alternatively drawn, as shown in Fig. 4.21.
If the first phase, say R or A phase starts at slot no.2, the Y or B phase should start at 120
0
/15
0
= 8 slots away ie., in slot (2 + 8 = ) 10, and the B or C phase should start at (10 + 8 =) 18.
Slots per pole per phase = = 4. Thus a phase group has 4 slots.
Coil span =
24
2
= 12 slots. This is an even number and hence winding is not possible
with a coil span of 12 slots. So a coil span of 11 slots is used.
Starting R phase in slot no. 2, the coil side in slot no. 2 is connected to the coil side (2 + 11
= ) 13. The coil side 14 is connected to coil side (14 + 11 = ) 25, ie., 1. The coil groups are
connected in such a manner that their emfs add. The windings of the other phases are also
similarly completed.
The current directions marked in Fig. 4.21, is an arbitrary direction at any instant.
Fig. 4.19 - Coil group connections for whole coil winding
24
3x2