# Self-inductance of a toroid with a rectangular cross section

Tags:
1. May 17, 2018 at 7:10 PM

### Ravasash

I have found answers on how to calculate the self-inductance of toroid of rectangular cross section, however my question says that "The winding are seen as a thin homogeneous currentlayer around the core" (excuse the translation). What does that mean for N? Does it mean N=1?

2. May 17, 2018 at 8:16 PM

### Hesch

Yes.
Say that the original values are: N = Norg , I = Iorg.
In the approximated model the values become:
Napp = 1 , Iapp = Iorg * Norg.
The reason for this approximation is that the coil is formed like the thread on a screw, which make calculations difficult.