Superconducting Fault Current Limiter (SFCL) can be regarded as a key component for future electric power systems which are capable of contemporarily eliminating the hazards during faults by increasing the short-circuit power of an electric network. That is attributed to the behaviour of resistive SFCL (R-SFCL) and inductive SFCL (I-SFCL) devices which show negligible resistance and reactance, respectively, under normal operating conditions and reliably switch to a high impedance state in case of extra-current. This paper presents a comparative study for the use of R-SFCL and I-SFCL by investigating their impacts on the shortcircuit calculations of a high voltage line. The case study is for a 220 kV transmission line in the northern transmission network of Algeria which is subjected to a phase to ground fault in the presence of a fault resistance. The impact of the impedance of SFCL (ZSFCL), which varies between minimum and maximum values for these two SFCL devices, is studied to show its effect on the short-circuit parameters including symmetrical current components, transmission line currents, voltage symmetrical components, and transmission line voltages, without and with SFCL devices. Presented theoretical analysis is verified by simulation results.
Computational homogenization is demonstrated as a potential analysis tool that can be used directly to predict the property structure relationships of many existing classes of composites. Based on finite element simulations, using the Zebulon structures calculation code, the present study is devoted to computation and estimation the effective behavior of the nonlinear composite materials with randomly identical elastic perfectly plastic parallel cylindrical fibers distribution in linear elastic matrix phase. The parameters of effective behavior of the composite will be expressed. These parameters are the effective elastic tangent modulus, effective plastic tangent modulus and effective yield stress. The proposed method can be readily applied to compute the parameters of effective behavior composite, using a new proposed analytical expression based on the volume fraction and effective Young’s modulus of each component. A good agreement between expression and simulation results is observed. Several examples are shown.