DC Shunt Motors
In these motors, the field and the winding are connected in parallel. They are used in applications where there is minimal change in speed as the motor is loaded. The provide medium torque while starting.
DC Series Motors:
These motors are used for applications requiring high starting torque. Here, the field and the winding are connected in series. These motors can be used in applications requiring high starting torque such as in traction related applications. The load on these motors must never be reduced to zero as this may result in excessive speed.
Permanent Magnet Motors:
These are used in applications which require greater reliability. Here, the field is made up of permanent magnets. The efficiency of the motor is higher. Speed can be controlled by varying the voltage of the armature.
Compound wound motors:
These motors combine the features of shunt and series motors. They have on field winding connected in series to the armature and another field winding connected in parallel. They provide a heavy starting torque. This kind of motor can be used for loads which are not sensitive to speed variations.