1. ConductorActive length of wire of winding is called conductor in which the EMF get generated on flux linkage.
A turn consists of two conductors situated one pole pitch apart and connected in series.
3. CoilA coil may consist one turn or several turn situated on one coil pitch apart. The coil consist one turn is called single turn coil and the coil consist more than on turn is called multi turn coil.
4. Coil side.
Each single turn have two coil side . one coil side of single turn are called coil side .
5. Coil span or coil pitchThe distance between two coil sides is called coil span or coil pitch
6. Pole pitchThe distance between starts of two continuous poles (N & S ), is called pole pitch it is generally taken 180 degree.
7. Phase spreadThe distance between start of two continuous phase is called phase spread, it is 120 degree.
• Classification of motor winding
• According to pitchAccording to pitch there are two type of winding
If coil span is less than one pole pitch then it is called short pitch winding. Here coil span is 150 degree.
2. Short pitch winding
Advantage of short pitch windingIt is economical
It is light in weight
Disadvantage of short pitch winding
Possibility of generation of harmonics and vibration in shaft.
• According value of slots/pole/phaseIn this base it is divided in two parts
1. Integral slot windingIf number of slots/pole/phase is a integer value then it is integral slot winding
2. Fractional slots winding
If number of slots/pole/phase is not a integer value then it is fractional slot winding
Advantage fractional slots winding
- The fractional slots winding make it possible to reduce the no of slot in motor and that’s why to reduce the size and price of motor.
disadvantage of fractional slots winding
- The motor having fractional slots winding are less efficient and capable to carry the load.