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Two-pole machine
Figure 3.1 depicts a two-pole machine in which the stator poles
are constructed in such a way as to project closer to the rotor than
to the stator structure. This type of construction is rather common,
and poles constructed in this fashion are called salient poles.
Note that the rotor could also be constructed to have salient
poles.

Figure 3.2 - Cross section of DC machine

Direct Current Motor (Rotor, Stator)
A representative DC (direct current) machine was depicted in
Figure 3.2 above, with the magnetic poles clearly identified, for
both the stator and the rotor.
Figure 3.1 is a photograph of the same type of machine. Note
the salient pole construction of the stator and the slotted rotor. As
previously stated, the torque developed by the machine is a
consequence of the magnetic forces between stator and rotor poles.
This torque is maximum when the angle γ between the rotor and
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