DC Shunt Motor

Discussion in 'Electronics Homework Help' started by vick5821, Jun 5, 2013.

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Jan 22, 2012
2. davennModerator

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Sep 5, 2009
can you post the diagram here

I have to register to see that link

Dave

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Jan 22, 2012
Here you go

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4. duke37

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Jan 9, 2011
The shunt winding produces a magnetic field.
The armature is the rotating part.

There is no difference between a motor or generator in this configuration.
If the armature is rotated in the field, it will produce a voltage (back EMF). If this voltage is below the applied voltage, the motor takes current. If this voltage is at the applied voltage, there will be no current.

If there is no torque and no friction (some hopes!), then the speed will rise till the two voltages match and the armature current will be zero. There will of course need to be a shunt, field current.

5. vick5821

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Jan 22, 2012
If there is no armature current, how the armature develop the voltage and rotate ? Hehe

6. duke37

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Jan 9, 2011
A very good point. It will never happen because there will be friction to slow the armature down as I pointed out.

The only thing perfect in this world is me !

7. Merlin3189

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Aug 4, 2011
Because there is a current in the field winding producing a magnetic field. A coil rotating a a magnetic field generates an emf. At the ideal free-running speed this will exactly equal the applied Voltage, so no current flows.
Though, as has been said, this never really happens, so there will be some current to generate the torque to overcome the losses.