The distribution factor is a measure of how the EMF induced in a distributed winding compares to the EMF induced if the winding were concentrated in one slot. It is given by the formula:

$$K_{d}=\frac{EMF\:induced\:in\:distributed\:windings}{EMF\:induced\:in\:concentrated\:windings}$$

• Concentrated Winding: All the coils of a phase under one pole are grouped in a single slot.
• Distributed Winding: The winding is spread across multiple slots under a pole to achieve a more sinusoidal waveform and reduce harmonics.

Pitch factor (Kp):

The pitch factor accounts for the difference between the resultant EMF of short-pitched coils and the resultant EMF of full-pitched coils. It is defined as:

$$K_{p}=\frac{Resultant\:EMF\:of\:short-pitched\:coil}{Resultant\:EMF\:of\:full-pitched\:coil}$$

• Full-Pitched Coil: The coil spans 180° electrical (one pole pitch), resulting in maximum induced EMF.
• Short-Pitched Coil: The coil span is less than 180° electrical, reducing the EMF to minimize harmonics.