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DC Permanent Magnet Motor Dynamic Braking Theory
In operation, a permanent magnet (PM) field DC motor has the
armature connected to its DC power supply. The interaction of the
magnetic field created by the field and the current flowing in the
armature winding causes the motor to run. A voltage called the
counter electromotive force (CEMF) is generated in the armature
conductors, when rotated in a magnetic field.
When the motor is running, the CEMF opposes the power supply
voltage and limits the armature current to a sufficient value to supply
adequate output shaft torque. Braking is accomplished by
disconnecting the armature from the DC power and shorting the
armature leads with a current limiting resistor. As soon as this is
done, the armature and its driven load will begin to stop.
Dynamic Braking
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