Cable Inductance
L = K + 0.2 *loge(2S / d ) (mH/km)
Where:
S = Axial spacing between conductors within the cable, or
Axial spacing between conductors in a trefoil group, or
1.26 x phase spacing for a flat formation of 3 single core cables
0.5 x pcd of neutral screen for single core neutral screen cables (mm).
d = conductor diameter (or for shaped designs, the diameter of an equivalent circular conductor (mm).
K = constant relating to the conductor formulation
No Cable K(50Hz)
1 0.0500
3 0.0778
7 0.0642
19 0.0554
37 0.0528
61 and over 0.0514
Recommended Reference Books
1. Electrical Energy System Theory - An introduction O.L. Elgerd
2. 2. Elements of Power System Analysis W.D. Stevenson Jr.
3. Course in Electrical Power C.L. Wadhwa
4. Power System Analysis Nagrath and Kothari
5. Power System Analysis & Design B.R. Gupta, Wheeler Publishing.
NOTE:
For additional details, search in the net for Inductance and Geometric Mean Distance (GMD)
