How to calculate speed voltage from Maxwell's laws

  • Thread starter darkfeffy
  • Start date
  • #1
17
0

Main Question or Discussion Point

Hi,

In classical induction machine analysis, the induced voltage (or curl of the electric field) is equal to the time rate of change of the magnetic field (B) plus the 'speed voltage'. This is understood very easily from electrical circuit models of the machine.

However, going purely from Maxwell's equations (1. div(E) = rho/epsilon; 2. div(B) = 0; 3. curl(E) = -dB/dt; 4. Curl(B) = mu(J + epsilon*dE/dt) ) how can one arrive at the same observation as above?

Thanks
e.
 

Answers and Replies

  • #2
jtbell
Mentor
15,544
3,453
What is "speed voltage"? I don't remember ever seeing that term before, in American English. Perhaps there is a language-translation problem?
 
  • #3
17
0
Hi Jtbell,
Thanks for your response. I was reading a book on linear induction motors, and therein it was written:

[itex]\frac{de}{dx}[/itex]=[itex]\frac{db}{dt}[/itex] + v[itex]\frac{db}{dx}[/itex]

The first term is referred to as a transformer voltage, and the second, a speed voltage. I want to know how to get this from Maxwell's laws. I recently read something about reference frames; I think my answer lies in that direction.

Best
e.
 

Related Threads on How to calculate speed voltage from Maxwell's laws

Replies
4
Views
2K
Replies
2
Views
6K
Replies
3
Views
581
  • Last Post
Replies
4
Views
4K
Replies
9
Views
6K
Replies
2
Views
1K
Replies
2
Views
2K
Replies
1
Views
381
Replies
13
Views
564
Replies
21
Views
3K
Top