Electric Stresses in an HVDC Cable Through Joint

Longitudinal and radial stresses in a hvdc cable through joint are computed using a finite difference method. The joint and associated cable are rated at 266 kV d. c., 1200A and assumed buried to a depth of l.lm in homogeneous soil of thermal resistivity 1.2 deg C-m W-1. Initially the temperature distribution is determined and the node to node finite difference resistances in the electrical representation calculated using the relationship, σ= σexp(αθ+ ßE) with an assumed voltage and stress distribution. A revised stress distribution is then computed, the nodal resistances adjusted to the new stresses and the iterative process repeated until the nodal voltage changes are below a prescribed limit.