Short-Circuit Current Limitation Through 2G YBCO Resistive-Type SFCL Devices: A Model for Technical and Economic Comparison With Traditional Air-Core Reactors

In this paper, a methodology has been developed to perform techno-economic comparisons between superconducting fault current limiters (SFCL) devices and air-core reactors to be used for short-circuit current limitation following a parameterized approach. The methodology is based on the development of models dedicated to the SFCLs design, to the calculation of the electrical quantities in the grid under study, and to the economic analysis of the related costs. As an example of the developed methodology application, a parameterized study has been carried out with respect to the desired limitation and a comparison between SFCLs and air-core reactors installation in a test grid has been performed. In total, 30 different values of limitation factor have been fixed and, for each of them, design calculation of the device, its impact in the grid, both in steady-state and in transient regime, and the related economic analyses based on hypotheses of capital and operating costs (derived from the experience of Ricerca sul Sistema Energetico in the development and installation of resistive SFCL) have been carried out. The main outcome is that, for a given tariff plan, for a grid initial power factor and for a wide range of limitation factor values, it is possible that the installation of SFCL devices instead of air-core reactors may guarantee a time of return on investment shorter than ten years.