DC series motors are widely used in industrial applications due to their high starting torque, featuring a stator made of pole shoes and field windings, and a rotor with armature conductors. The motor operates on the Lorentz law, where current-carrying conductors in a magnetic field experience a force, allowing the rotor to turn. The rotor's rotation direction can be verified using Fleming's left-hand rule, which illustrates the relationship between magnetic field direction, current flow, and force exerted.

1. DC Series Motors
• Dc series motors are highly utilized in so
many industrial application due to its high
starting torque characteristic

2. Construction
Stator:
• Generally the outer stationary part is stator consist of Frame
or yoke inside which pole shoes are bolted projecting
Inwards .
• Main fields (bigger ones) are always in even number or in
number of pairs
• Inter poles (smaller ones) are also built in even number or in
number of pairs
• One each pole shoe cropper or aluminum winding is wound
known as field winding which carries the field current to
create static magnetic poles on the stator.
• In all dc machines Filed winding are wound on stators.
DC Series Motors
Stator

3. Construction
Rotor:
• Central rotating part is known as rotor built up of laminated
core having multiple number of slots(axially oriented) on
outer periphery.
• The rotor slots consist of armature conductors are connected
to form close type winding.
• Winding could be wound in “lap” or “wave” patterns
• The complete core is on high grade stainless steel shaft also
keyed to it so as to avoid slipping.
• The shaft is also mounted with commutator ring made up of
multiple number of commutator segments.
• From each commutator segments ends of the armature
winding are connected.
DC Series Motors
Stator

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5. Main Field Pole
Inter-pole
Yoke
Pole Shoe
Armature/ Rotor core
Armature winding
Commutator
Shaft
Inter-pole Winding
Field Winding
Stator Rotor
DC Series Motors

6. Construction
• Rotor is placed inside the stator and separated from it by small
air gap and free to rotate.
• Rotor is supported by the end cover on both side of the motor
frame with the help of bearings.
• Brushes feeds direct electric current in to the armature winding
pressing on commutator segment.
• Number of brushes are always equal to number of main poles
• Four carbon brushes are in this case of four pole shunt motor
• brushes are placed in intern polar region.
DC Series Motors

7. Working
• It works on the principle of Lorentz Law, which states
that “the current carrying conductor placed in a
magnetic field experience a force.
• Fields are produce by the main field poles and always
in alternate pattern.
• winding of all main poles are connected in series in
such a way only two terminal remains.
• Field lines emerges radialy inwards and converges in
to south poles placed next to every north pole.
• Field winding is made up of so many turns of fine
copper or aluminum wire.
DC Series Motors
Stator

8. Working
• Simple representation of field winding.
• Current enters in to first pole form one end and exit
form another terminal from last pole.
DC Series Motors

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10. Working
• Verifying direction of each pole
magnet using right hand thumb
rule.
DC Series Motors

11. Working
• Wiring connection of burses.
• Two brushes are given Positive
voltage and two are given negative.
DC Series Motors

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13. Working
• When dc current is feed in to the commutator using brushes.
• The current flows through the armature/rotor winding in such a way that
the coil sides/conductors under the influence of North pole of stator/field
carry current in one direction represented by dot in the diagram.
• The current flows in the coil side/conductor under the influence of south
pole carries current in opposite direction represented by cross in the
diagram.
DC Series Motors

14. DC Series Motors

15. Working
• Verifying the direction of force on the
conductors of Left hand side of rotor.
• Applying Fleming left hand rule.
• Index finger – direction of field
• Middle finger – direction of
current
• Thumb – Gives direction of force
DC Series Motors

16. Working
• Verifying the direction of force on the
conductors of top side of rotor.
• Applying Fleming left hand rule.
• Index finger – direction of field
• Middle finger – direction of current
• Thumb – Gives direction of force
DC Series Motors

17. Working
• Verifying the direction of force on the
conductors of right side of rotor.
• Applying Fleming left hand rule.
• Index finger – direction of field
• Middle finger – direction of
current
• Thumb – Gives direction of force
DC Series Motors

18. Working
• Verifying the direction of force on the
conductors of bottom side of rotor.
• Applying Fleming left hand rule.
• Index finger – direction of field
• Middle finger – direction of
current
• Thumb – Gives direction of force
DC Series Motors

19. DC Series Motors

20. Working
• After verifying direction of force on all
the conductors, it could be conclude
that the rotor is getting torque in
clock wise direction
DC Series Motors

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22. DC Series Motors

23. DC Series Motors

24. DC Series Motors

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