Concentric Winding (EED)

in this PPT I Gave Information To ac Concentric winding And its placing . and i gave solve example and calcution of concentric winding.

1. Electrical E lements Design (2150904) Active Learning Assignment on Concentric Windings Prepared By: Patel RajalKumar H. (160123109013) Guided By : Prof. Purv Mistry Electrical Department Batch-B3 Gandhinagar Institute of Technology 1

2. Introduction Gandhinagar Institute of Technology 2 Three-phase concentric winding consists of coil groups laid in the slots so that all the coils of each group are concentric. That is, the coil with the smallest slot pitch is surrounding by the coil with the next larger slot pitch and so on to make up a coil group. Each coil consists of several turns and the cross-over from one coil to the next is indicated by a short slanted line (jumper).

3. AC Armature Windings Single layer winding Double layer winding Concentric winding Mush winding Lap winding Wave winding Hemitro-pic Whole coil winding Integral slot Fraction-al slot Integral slot Fraction-al slot Types of AC armature winding Gandhinagar Institute of Technology 3

4. Concentrated armature winding Concentrated winding is employed where number of slots on the armature is equal to number of poles in the machine. This armature winding of alternator gives maximum output voltage but not exactly sinusoidal. Here, number poles = number of slots = number of coil sides , which is shown in below fig. Here, one coil side is inside one slot under one pole and other coil side inside other slot under next pole. Gandhinagar Institute of Technology 4

5. Gandhinagar Institute of Technology 5

6. Construction of concentrated winding Gandhinagar Institute of Technology 6 In order to construct the diagram for a winding, the following data must be known: S - The number of slots in the stator P – The number of poles m – The number of phases Y S – The pitch of the winding a – The number of parallel circuits in the windings

7. The pitch of the winding is determined by the formula The pitch is the distance between two sides of a coil expressed as the difference between the numbers of the slots in which the sides lie. Another important value of the winding of ac machines is the number of slot per phase per pole denoted by the letter q. It can be determined by the formula Gandhinagar Institute of Technology 7

8. Example#1: on concentric winding Gandhinagar Institute of Technology 8 Given data S=24; p=4;m=3; a=1; type=Concentric Solution The number of coil groups, K The number of slots per pole per phase, q Coil pitch The shorter coil pitch = Y S -1=6-1=5   Full-Pitch ( average pitch) i.e. there are two coils in a group i.e. there is two coil groups per phase

9. The larger coil pitch = Y S +1=6+1=7 The electrical angle, The angle between adjacent slots, The distance between the beginning of each phase,  If the beginning of Phase A is slot 1, then the beginning of phase B is slot 1+  =5 and the beginning of phase C is slot 1+2  =1+8=9   Gandhinagar Institute of Technology 9

10. PROCEDURE FOR CONSTRUCTING OF CONCENTRIC WINDINGS Gandhinagar Institute of Technology 10 Data: S= 24, P = 4, a = 1, q = 2, K = 6

11. Coil Groups of Phase A Gandhinagar Institute of Technology 11 The first and second slots will be occupied by left-hand sides of the first coil group of phase A. Leave four, or 2q slots free for other two phases occupy slots 7 & 8 with the right hand side of the first coil group. Next to it will lie a second coil group of the same size which occupies slots 9,10,15,16.

12. Coil Groups of Phase B Gandhinagar Institute of Technology 12 In order to find, where the second phase (B) should begin, it is necessary to know the angle between slots in electrical degrees.  =180.P = 180.4 = 720 – Electrical degree The angle between adjacent slots, The distance between phase beginnings will have  

13. Coil Groups of Phase C Gandhinagar Institute of Technology 13

14. Current direction Gandhinagar Institute of Technology 14 N 1-6 N 13-18 S 7-12 S 19-24

15. Phase A – Coil groups interconnection Gandhinagar Institute of Technology 15

16. Phase B – Coil groups interconnection Gandhinagar Institute of Technology 16

17. Phase C – Coil groups interconnection Gandhinagar Institute of Technology 17

18. Terminals Gandhinagar Institute of Technology 18

19. Thank You… Gandhinagar Institute of Technology 19