Implementation of Resistive Type Superconducting Fault Current Limiters in Electrical Grids: Performance Analysis and Measuring of Optimal Locations

Abstract

In the past few years there has been a significant rise in the short-circuit current levels in transmission and distribution networks, it due to the increasing demands on power and the addition of sources of distributed generations. It leads to the need of integration of novel protection systems such as the superconducting fault current limiters (SFCLs), ... . SFCL models on the electric distribution networks largely rely on the insertion of a step or exponential resistance that is determined by a predefined quenching time. However, beyond the framework of these models, the study of the performance, reliability, and location strategy for the installation of sole or multiple SFCLs in power grids still lacks of proper development leading to the utter need of comprehensive and systematic studies on this issue. In this paper, we expand the scope of the aforementioned models by considering the actual behaviour of a SFCL in terms of the temperature dynamic power-law dependence between the electrical field and the current density. Our results are compared with step-resistance models for the sake of discussion and clarity of the conclusions. Both SFCL models were integrated into a power system model built based on the UK power standard, and the impact of these protection strategies on the performance of the overall electricity network was studied. As a representative renewable energy source, a 90 MVA wind farm was considered for the simulations. Three fault conditions have been simulated, and the figures for the fault current reduction predicted by both fault current limiting models have been compared in terms of multiple current measuring points and allocation strategies...