DC Motors
DC MOTOR THEORY
DC MOTOR THEORY
DC motors are widely used to drive various equipment. The speed
and torque produced in a DC motor depends on a variety of factors.
EO 1.1
Using the right-hand rule for motors, DETERMINE the
direction of the magnetic field, direction of current flow,
or force on a conductor.
EO 1.2
STATE the function of torque in a direct current motor
and how it is developed.
EO 1.3
DESCRIBE how Counterelectromotive Force (CEMF) is
developed in a DC motor.
EO 1.4
DESCRIBE the relationship between field current and
magnetic field size in a DC motor.
EO 1.5
STATE the function of the CEMF that is developed in
a DC motor.
EO 1.6
DESCRIBE how the speed of a DC motor is adjusted.
EO 1.7
DESCRIBE the relationship between armature current
and torque produced in a DC motor.
Inducing a Force on a Conductor
There are two conditions which are necessary to produce a force on a conductor.
The conductor must be carrying current.
The conductor must be within a magnetic field.
When these two conditions exist, a force will be applied to the conductor, which will attempt to
move the conductor in a direction perpendicular to the magnetic field. This is the basic theory
by which all DC motors operate.
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