Skip to Main Content
This paper builds on a previously published development work involving a novel thermal field sensitivity model for underground cable systems, based on finite elements, which has been verified by experimental laboratory measurements. The paper reports on a new approach to underground cable thermal field optimisation using a proposed concept of perturbed finite-element analysis. This concept is not restricted to the conventional thermal field evaluation; rather it involves two main achievements. First, it derives sensitivity coefficients associated with various cable parameters of interest, and provides a quick sensitivity methodology based on the finite element model, to assess the cable thermal performance subjected to variations in the cable thermal circuit parameters, without repeating the finite element analysis for each possible parameter change. Second, it introduces an optimisation model for the underground power cable thermal circuit, based on generated gradients. The derived sensitivity coefficients are utilised for another important advantage in calculating the gradient of the desired objective function. This general framework of power cable performance optimisation uses the perturbed finite element method, which enables calculation of the objective function value and its gradient, without sacrificing the model accuracy. The developed algorithm was applied to various benchmark cable systems of 69 and 380 kV for different practical cable performance optimisation objectives.