Skin effect impact on current density distribution in OPGW cables

The paper describes an analytical approach to the issue of skin effect on current or current density distribution over the cross-section of the tube type conductors. The same cross-section can analogously be taken for any multi-layer conductor of different construction designs. Due to the skin effect, the current flows towards the conductor surface, the result being an uneven current distribution over the conductor cross-section. A mathematical algorithm is given enabling determination of the current density distribution over the tube type conductor cross-section. It is computed with the Maxwell's equations from the theory of electromagnetic fields and by using Bessel's functions of the first and second order. With thus implemented model the authors developed an algorithm for the current density determination with consideration of the skin effect in a multi-layer optic cable of the OPGW type. Results are shown of the current density distribution and temperature variations as detected in individual layers of such conductor during heating at the short-circuit current of 15.4 kA and in the duration of 1 s.