Nation Institute for Nuclear and High Energy Physics

Inductance calculations
Straight round and rectangular conductors

 
Pieter J.T. Bruinsma, PA0PHB
Pieter J.T.Bruinsma
   Engineering notes   

The inductance for long straight-wires and rectangular bars will be calculated.
The permeability of the medium is assumed to be 1. For other media, simply multiply by the relative permeability.

In all cases, the current is assumed to flow in the outer surface of the conductors. The approximate formulas used to calculate the inductance can be found in Radio Engineering Handbook by Terman. Most of them are derived in the book "Inductance Calculations" by F. W. Grover.

Select units meter cm inch
Operating frequency MHz
Relative Resistance with respect to copper

 

Twin lead - wide separation

Length


Wire spacing


Wire diameter

microH
two 
separate wires
  • S:
  • distance from center to center
  • D:
  • wire diameter


     

    Straight wire with ground as current return path

    Length


    Height above ground


    Wire diameter

    microH
    a 
wire above a ground plane
  • H:
  • height of center from ground plane
  • D:
  • wire diameter

    Straight round wire

    Length


    Wire diameter

    microH
    a wire above a ground 
plane
  • D:
  • wire diameter

    Rectangular bar

    Length


    Width


    Thickness

    microH

  • W:
  • Width
  • T:
  • Thickness

    Inductance geometries

    Single-turn coils

    Straight conductors

    Muliti-turn

    References

    Gover (google)

    Thomson

    Bueno

     
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    Last modified 2010/05/25