DETERMINATION OF THE POWER CABLES SYSTEM REDUCTION COEFFICIENT MATRIX

Abstract

The work presents original theoretical bases of the mathematical model for the determination of the power cables system reduction coefficient matrix. The matter at hand is a new and completely general mathematical model which can take into consideration an arbitrary number and arrangement of a single-core cable system arranged in a treefoil formation. As a matter of fact, the concerned reduction coefficient matrix takes into consideration the real (full) electromagnetic impact which dominates the pertaining power cables, in the conditions of occurrence of one-pole short circuit. The reduction coefficient matrix is characterized by having elements dependant exclusively on electromagnetic and geometrical properties of the very power cables, their positioning and on the geophysical properties of their route, as well as on the frequency of the currents flowing through the power cables. The application of the model deliberated here enables a far more accurate estimation of the current distribution in the power cables system than would be possible by applying separate reduction factors of the present power cables. At the same time, the deliberated model is simple for application and entirely general. The application of the presented theory and the developed mathematical model is also shown on the example of the general system of power cables with nominal voltage 110 kV.