Longitudinal Impedance Calculation Method for Cable Lines with Single-Core High Voltage Cables

For more than 20 years, cable lines (CL) made of single-core cables with cross-linked polyethylene (XLPE) insulation have been massively used in the world for all classes of rated voltage from 6 kV and above. Unfortunately, in national standards and catalogs of numerous cable factories, there were no calculation methods that would allow us to find the CL active and inductive impedances of positive and zero sequences, depending on the cable screen bonding/grounding schemes and screen cross-section. The article offers simple formulas that allow calculating the longitudinal active and inductive impedances of CL depending on the screen bonding/grounding schemes (one-side grounding, both-sides grounding, screens cross-bonding) and depending on the sequence (positive or zero).