Cableizer ®

Geometric mean distance between phases of the same system, short-circuit

In case of short-circuit the phases of an AC cable system will repell each other. If the cables are inside a duct it will increase the distance between the phases.

Symbol
$GMD_k$
Unit
m
Formulas
$GMD+2\left(\frac{Di_d}{2}-\frac{D_e}{2}\right) \frac{1}{1000}$separate ducts
$\left(Di_d-D_e\right) \frac{1}{1000}$common duct, 3 cables
$\left(Di_d-D_e\right) \sqrt{2} \frac{1}{1000}$common duct, 2 cables
Related
$D_e$
External diameter object [mm]
$Di_d$
Inner diameter duct [mm]
$GMD$
Geometric mean distance between phases of the same system [m]
Used in
$F_{k,2}$
Mechanical force phase-to-phase fault [kN/m]
$F_{k,3}$
Mechanical force three-phase symmetrical fault [kN/m]