Case Studies for Optimal Cable Line Placement and Sheath Grounding to Increase its Operational Characteristics

X-linked polyethylene (XLPE) cables are widely dispersed in grids of 110 kV and supposed to be used in specific environmental conditions because of its compactness and higher structural durability, resistance, and stability. These conditions may include laying in urban centers and cites or through different watercourses when traditional overhead lines application is impossible or unacceptable. Wherein, XLPE cables require a precise calculation of geometrical parameters of their laying, identification of optimal sheath grounding and phase transposition, etc. For example, close cable spacing may lead to thermal damages of all cores after single-phase short circuits. In its turn, the cable sheath transposition allows transfer capacity increasing, which is critical in grids of metropolises. In this paper, the authors propose a series of case studies and calculations, which allow identifying an optimal solution for three-phase cable line placement.