Effectiveness of Superconducting Fault Current Limiting Transformers in Power Systems

Abstract

Abstract-Superconducting devices have emerged in many applications during the last few decades. They offer many advantages including high efficiency, compact size, and superior performance. However, the main drawback of these devices is the high cost. An option to reduce the high cost and improve the costbenefit ratio is to integrate two functions into one device. This paper presents the superconducting fault current limiting transformer (SFCLT) as a superior alternative to normal power transformers. The transformer has superconducting windings and also provides fault current limiting capability to reduce high fault currents. The SFCLT is tested in two power system models: a 7 bus wind farm based model simulated in PSCAD and on the 80 bus simplified Australian power system model simulated in RTDS. Various conditions were studied to investigate the effectiveness of the fault current limiting transformer.  Index Terms-Transformers, superconducting, fault current limiters .

Experimental and Simulation Study of Resistive Helical HTS Fault Current Limiters: Quench and Recovery Characteristics

“…where c0 = 2.09×10 9 A/m 2 is the critical current density at the initial temperature 0 = 77 K, the boiling point of LN2. c = 92 K is the critical temperature, and is the density exponent, 1.5 was used here [34]. When the resistivity of superconducting layer increases, the current starts to flow through other layers depends on their resistances.…”

Impact of Copper Stabilizer Thickness on SFCL Performance with PV-Based DC Systems Using a Multilayer Thermoelectric Model

“…Equation ( 3) is applicable when the current density increases beyond the critical current density of the tape (I c ), while the temperature is still below the critical temperature (T c ), which equals 93 K. The critical current density varies with temperature and may be computed using (4), where J co is the critical current density at 77 K, the boiling temperature of LN 2, and coolant. The exponent a is the density exponent and is equal to 1.5 [59]. Equation ( 4) is only applicable for T o < T < T c .…”

DC Fault Study of a Point-to-Point HVDC System Integrating Offshore Wind Farm Using High-Temperature Superconductor DC Cables

“…As the volume and specific heat capacity of each material in the tape are different, the heat capacity of each material is calculated individually by multiplying its specific heat value by the volume and the density of the material. In this paper, the heat capacities of PPLP insulation, the substrate layer, the stabilizer layer, the GdBCO layer and the copper former are considered [23].…”