Numerical Analysis of the Current and Voltage Sharing Issues for Resistive Fault Current Limiter Using YBCO Coated Conductors

Abstract

YBaCuO-coated conductors offer great potential in terms of performance and cost-saving for superconducting fault current limiter (SFCL). A resistive SFCL based on coated conductors can be made from several tapes connected in parallel or in series. Ideally, the current and voltage are shared uniformly by the tapes when quench occurs. However, due to the non-uniformity of property of the tapes and the relative positions of the tapes, the currents and the voltages of the tapes are different. In this paper, a numerical model is developed to investigate the current and voltage sharing problem for the resistive SFCL. This model is able to simulate the dynamic response of YBCO tapes in normal and quench conditions. Firstly, four tapes with different c 's and n values in -power law are connected in parallel to carry the fault current. The model demonstrates how the currents are distributed among the four tapes. These four tapes are then connected in series to withstand the line voltage. In this case, the model investigates the voltage sharing between the tapes. Several factors that would affect the process of quenches are discussed including the field dependency of c , the magnetic coupling between the tapes and the relative positions of the tapes.

Computation of Losses in HTS Under the Action of Varying Magnetic Fields and Currents

“…4) Fault Current Limiters: For resistive type superconducting fault current limiters, it is preferable to contain a long length of superconductors in a small volume. One type of SFCLs uses an array or matrix of superconducting tapes [319], [320], [321]. For ac loss calculation, a stack of superconductors can be modeled for this type of SFCLs [321].…”

“…One type of SFCLs uses an array or matrix of superconducting tapes [319], [320], [321]. For ac loss calculation, a stack of superconductors can be modeled for this type of SFCLs [321]. Another design is to use a non-inductive superconducting coil [174], [285].…”

Resistive-Type Superconducting Fault Current Limiters: Concepts, Materials, and Numerical Modeling

“…However, for 2D systems with J constrained to flow in only one direction reliable solutions for the electromagnetic problem can be achieved, whilst the heat transfer problem is solved via the transient conduction equation. This strategy has been used for describing the electro-thermal properties of single coated conductors [52] - [53], stacks of 2G HTS tapes [54], and 2G HTS coils [55], as active elements of the SFCL. For the sake of simplicity, COMSOL also allows the 1D modelling of SFCL, with differences between the theory and experimental measurements of about 20-40% in 2G HTS tapes, decreasing for the case of MgB2/metal conductors [56].…”

Numerical simulations of electromagnetic behavior and AC loss in rectangular bulk superconductor with an elliptical flaw under AC magnetic fields

“…The simulations results agree well with the analytical and experimental results. After the heat transfer module was added, the problems of superconducting fault current limiters [22,23] and the quench propagation inside a HTS coil [24] could be investigated. When the magnetic field dependent permeability and ferromagnetic loss of the magnetic substrate were taken into account, a new FEM model using the H-formulation was proposed to compute the electromagnetic characteristics and AC losses in YBCO tapes with magnetic substrates by Nguyen et al [25].…”