Performance analysis of HTS fault current limiter combined with a ZnO varistor

The superconducting technology nowadays is an innovation in the field of the electrical power supply. Using HTS in fault current limiter (FCL) represents a new category of electrical equipment and a novel configuration of electrical network. In fact the high temperature superconductivity (HTS) make a relatively sharp transition to a highly resistive state when the critical current density is exceeded, and this effect has suggested their use for resistive fault current limiters. FCL is an important element in order to reduce system impedance, which permits an increase of power transmission. Furthermore, it allows additional meshing of a power system, which increases the power availability. The most significant features of the SCFCLs requested from the power system operating conditions are a limiting impedance, a trigger current level and a recovery time. In this paper, a model of HTS FCL using ZnO varistor is proposed. The effectiveness of this model is investigated through results of simulation in MATLAB/Simulink software. In addition it is illustrated the limiting feature of HTS FCL and protected role of ZnO varistor