Line Constants

Overhead line constants calculation library in Python.

Functions in the library include:

• calc_L_int: Calculates internal inductance of solid or tubular conductor
• calc_GMR: Calculates geometric mean radius (GMR) of solid or tubular conductor
• carsons: Calculates Carson's earth return correction factors Rp and Xp for self or mutual terms
• calc_self_Z: Calculates self impedance term (in Ohm/km)
• calc_mutual_Z: Calculates mutual impedance term (in Ohm/km)
• calc_Dubanton_Z: Calculates Dubanton approximation for self or mutual impedance (in Ohm/km)
• calc_Z_matrix: Calculates primitive impedance matrix
• calc_Y_matrix: Calculates primitive admittance matrix
• calc_kron_Z: Calculates Kron reduced matrix

Features currently not supported:

• Skin effect calculation for internal self impedance
• Input data validation, e.g. check that all phase conductor vectors are the same size

Validation

Output of line constants library example (simply run line_constants.py in the command line):

Corresponding line constants calculation in DIgSILENT PowerFactory 2017:

Impedance matrix:

Admittance matrix:

References

• Dommel, H. W., "Electromagnetic Transients Program Reference Manual (EMTP Theory Book)", Chapter 4, "Overhead Transmission Lines"
• Arrillaga, J., and Watson, N. R., "Computer Modelling of Electrical Power Systems", 2nd Edition, Wiley, 2005, Chapter 2.6

License & Copyright

Copyright (C) 2017 Julius Susanto. All rights reserved.

The code is distributed under the 3-clause BSD license found in the LICENSE file.