Tool Box

Wire Internal Inductance

Wire Internal Inductance

Internal Inductance Model
Internal inductance of a wire is:
wire_internal_formulaist
Units: Henries
Skin Depth is:
wire_internal_formula2nd
Units: meters

Description
Inductance calculated using this tool is the internal inductance of a straight, circular wire. In many circumstances internal inductance is negligibly small compared to external inductance. As frequency increases, internal inductance decreases due to skin effect.

Assumptions and Limitations
Dimensions are in meters.
Wires are assumed to have circular cross sections and to be straight over their length.
Wire is assumed to be homogeneous medium having permeability u=u0.
Wire relative conductivity Symbol-sigmaR.

Constants
Permeability of free space: Formula, Permeability of Free Space H/m
Conductivity of copper: Symbol-sigma0 = 5.98 x 10 7 S/m (Siemens per meter) at 20-degrees C

Reference: “Inductance Loop and Partial”, C.R. Paul, Wiley, 2010.

Inputs

Wire radius
r
Length
l
Frequency
f
Relative Conductivity
Relative Permeability

Outputs

Inductance: L = 
3.269e-8 H
Skin Depth:  = 
2.058e-4 m