Specifications
39
12345678910 11 12 13 14 15 16
17
18 19 20 21 22 23 24
N1 S1 S2N2
19
24
23
1
2
3
22
23
24
3
2
1
coil side 9, ie., pitch for larger coil is added to coil side 4. The front end of the coil side 9 is
connected to front side of coil side 5 to form concentric winding. Following the above procedure,
Table 4.3 gives the complete winding table for 4 pole 24 slot AC Machine.
Table 4.3 Single Phase Concentric Winding Table
S.No Front End Coil Side Back End Coil side
1 4 4 + 5 = 9
2 9 – 4 = 5 5 + 3 = 8
3 8 – 2 = 6 6 + 1 = 7
4 7 + 6 = 13 13 – 1 = 12
5 12 + 2 = 14 14 – 3 = 11
6 11 + 4 = 15 15 – 5 = 10
7 10 + 6 = 16 16 + 5 = 21
8 21 – 4 = 17 17 + 3 = 20
9 20 – 2 = 18 18 + 1 = 19
10 19 + 6 = 1 25 – 1 = 24
11 24 + 2 = 2 26 – 3 = 23
12 23 + 4 = 3 27 – 5 = 22
Draw 24 solid lines of equal length at equal distance. This represents the number of slots.
This also represents the number of coils, as this is a single layer winding. Then assign numbers
to the top side of the coils, as shown in Fig. 4.3. With reference to Table 4.3, complete the
winding diagram.
Fig.4.3 - Single Phase AC Concentric Main Winding Diagram
4.2 THREE PHASE WINDING
Single Layer Winding
Problem 1 : Develop a 3 phase, single layer concentric type of winding for a 2 pole ac machine
having 12 slots.
Solution : Slots per pole per phase = = 2
12
3×2