Prompt Title: Causes of harmonics.

Winding factors are used to describe the distribution of the magnetic field produced by the windings in an electric machine. There are two main types of winding factors: the distribution factor (Kd) and the pitch factor (Kp).

1. Distribution factor (Kd): The distribution factor takes into account the distribution of the winding over the pole pitch of the machine. It is defined as the ratio of the fundamental component of the air-gap flux to the flux produced by the winding alone.

The effects of the distribution factor are:

• A high distribution factor indicates a more uniform distribution of the magnetic field in the air-gap, which results in a higher efficiency of the machine and a smoother torque output.

• A low distribution factor indicates that the magnetic field is concentrated towards the pole tips, which can cause increased losses and a less smooth torque output.

2. Pitch factor (Kp): The pitch factor takes into account the effect of the coil pitch on the magnetic field produced by the windings. It is defined as the ratio of the emf induced in the winding by the fundamental component of the air-gap flux to the emf induced in the winding by the flux produced by the winding alone.

The effects of the pitch factor are:

• A high pitch factor indicates that the windings are distributed over multiple pole pitches, which results in a more uniform distribution of the magnetic field in the air-gap and a smoother torque output.

• A low pitch factor indicates that the windings are concentrated in a small area of the pole pitch, which can cause increased losses and a less smooth torque output.

In summary, both the distribution factor and the pitch factor affect the distribution of the magnetic field in an electric machine, which can affect its performance, efficiency, and torque output. A high distribution factor and pitch factor indicate a more uniform distribution of the magnetic field, resulting in better machine performance, while a low distribution factor and pitch factor indicate a more concentrated magnetic field, resulting in reduced machine performance.