The dynamic behavior of isolated cables is an important issue for the planning and operation of isolated power cables facilities. Thermal dynamic analysis provide valuable information such as the maximum time a cable supports an overload, or how conductor and sheath temperatures evolve under a variable load profile. This paper proposes a method to model the dynamic behavior of isolated cables from the thermal point of view. The model consists of a radial partition of the cable, modeling each resulting layer (insulation, jacket, soil, etc.) as thermal resistances and capacitors. In addition, the model deals with non-conductive layers (galleries, ducts, etc.) and also includes an electrical representation of the installation to obtain precise sheath currents. The resulting linear dynamic model is solved using eigenvalue analysis. The performance of the model is illustrated using a real underground installation. Accuracy of the proposed approach is checked comparing its results with those obtained using a finite element model of the installation. In addition, to illustrate the possible applications of the model, overload versus time plots and temperature evolution under a variable load profile are depicted.
Keywords: Power System Security, Total Transfer Capability, Sensitivity, Optimization, Active Power Generation Redispatch
17th Power Systems Computation Conference - PSCC'11. Estocolmo, Suecia. 22-26 Agosto 2011
Published: August 2011.