Reduce rotor voltage

Reduce rotor current

Increase the torque

Reduce the power loss

Cascade operation method

Rotor rheostat speed control

Changing the applied frequency method

Changing the number of stator poles method

Full pitch winding

Whole coil winding

Long chorded winding

Short chorded winding

More space is required

A stepped former is required

More difficult to shape the coils uniformly

It is not easy to make the end connection

3 slots

4 slots

6 slots

8 slots