DC motor rotor + stator : torque by attraction ?

Click For Summary
SUMMARY

The discussion centers on the torque generation in a DC motor, specifically addressing the interaction between the rotor and stator magnetic fields. The equation F = B*I is crucial in understanding how the current in the rotor creates a magnetic field (Brotor) that interacts with the stator's magnetic field. The confusion arises from the direction of magnetic flux, which varies based on location rather than being fixed. Ultimately, both magnetic field configurations can coexist without contradiction, resolving the initial misunderstanding.

PREREQUISITES
  • Understanding of electromagnetic principles, specifically F = B*I
  • Knowledge of magnetic field interactions in DC motors
  • Familiarity with rotor and stator configurations
  • Basic grasp of magnetic flux directionality
NEXT STEPS
  • Research the principles of torque generation in DC motors
  • Explore the role of magnetic fields in motor operation
  • Study the effects of rotor and stator alignment on performance
  • Learn about magnetic flux and its implications in electromagnetic systems
USEFUL FOR

Electronics engineers, students studying electromagnetism, and anyone involved in the design or analysis of DC motors will benefit from this discussion.

An1MuS
Messages
38
Reaction score
0
DC motor rotor + stator : torque by attraction ? [Solved]

So on that image there's a very simple dc motor.

Knowing that F = B*I, the force acting on the wire can be represented as on the image.
Also the current passing through the rotor will create a magnetic field, represented by Brotor, pointing downards.
Acording to the first image, it will rotate as if the magnetic fields align, because of the F = BI equation, so both magnetic fields would point in the same direction.

TlaMt.gif



On the other hand, here we just have that the opposite poles attract, so the force is for the magnetic fields to point in opposite directions.

Uaml2.jpg


I'm having some difficulty understanding this, because these concepts seem to contradict each other.

1Plpe.png


So where am i thinking wrong here?
 
Last edited:
Engineering news on Phys.org
Could it be because on the outside the flux of the rotor points upward ?

http://imageshack.us/f/14/asdadfq.jpg/
 
Ok i think I've come to grips to what's causing the confusion.

Since i saw the magnet flux from north to south, i assumed wrongly that South is where the flux vector always points.

But it seems it only points in the direction of the flux on that specific location. So both images are correct and this problem is solved.

magpart3a.gif
 

Similar threads

  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 18 ·
Replies
18
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 14 ·
Replies
14
Views
4K
Replies
2
Views
2K
  • · Replies 4 ·
Replies
4
Views
4K
  • · Replies 4 ·
Replies
4
Views
6K
  • · Replies 15 ·
Replies
15
Views
3K
  • · Replies 7 ·
Replies
7
Views
4K