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The High Temperature Superconductor (HTS) based flux pump is a useful device which is able to charge the HTS coil to a reasonably high magnetic field level. For a certain HTS flux pump, HTS tapes are used as the connections between the load loop and charging loop. It is a general method to use the soldering joints as the bridge to link superconducting layers. For this kA level flux pump, we used the HTS-copper joint to connect the HTS bridge, the charging loop, and the HTS load. We use the method of HTS-copper soldering by the IN52/SN48 ribbon with pre-tinning. Results demonstrate this soldering method was able to archive ultra low joint resistance, which is beneficial for this kA level flux pump.

It is a promising cable structure methodology to use conductor on round core (CORC) cables for large current density applications. In this study, a three-dimensional (3-D) CORC model was built from different thicknesses of the superconductor layers using finite element method. The AC losses exposed to a sinusoidal external magnetic field were calculated. Furthermore, we provide a recommendation to simulate a thicker model instead of the real physical thickness to save computation resources while maintaining a high accuracy.

This article analyzed the losses from the saturated iron-core superconducting fault current limiter (SISFCL) which could be potentially applied into a Voltage Source Converter based High Voltage Direct Current (VSC-HVDC) network. The mathematical model of SISFCL and the loss computation on High Temperature Superconducting (HTS) parts have been performed based on the FEM (finite-element method) combined with H-formulation solved by the COMSOL. Before the FEM modelling of SISFCL, the fault current statues were modeled using PSCAD. The operation performance of SISFCL was simulated as well based on the electromagnetic characteristics analysis, and the power dissipations in the HTS coils of SISFCL were calculated. Results demonstrate even with a DC system, there were certain amounts of loss happened in the HTS coils of SISFCL, if the SISFCL encountered a considerably high fault current.

This paper shows a new model of the anisotropic field dependence for modeling the High Temperature Superconductor (HTS) based Conductor on Round Core (CORC) transmission Cables. The modeling of CORC Cable was carried out using the finite-element method (FEM) and H-formulation model which put into the software COMSOL. This new model with the field dependence model was tested for both the 2D and 3D models of CORC cables. The simulations were performed with different conditions, e.g. different transport current and the gap angle between each HTS wires. This new field dependence model can contribute a good approximation of the real operating performance of CORC cables, and also build an upper limit of the AC loss. This model could be really beneficial for the design of CORC cables.

This paper presents a system-level loss study of the saturated iron-core superconducting fault current limiter (SI-SFCL) used in the voltage source converter-based direct current (DC) system. A multi-terminal VSC-based DC system equipped with SI-SFCLs was simulated in PSCAD, and its short-circuit fault process was modelled. The results of pole-to-ground fault current in the multi-terminal VSC-based DC system, with or without the SI-SFCL were compared. The data of fault current with SI-SFCLs was exported to the FEM model of SI-SFCL. Then, the instantaneous dissipation on the DC bias superconducting coil was investigated. Results show that the power loss of that DC system SI-SFCL during the pole-to-ground fault could be up to several kilowatts.

A conductor on round core (CORC) cable wound with REBCO tapes is promising for high current density applications. AC loss analysis can help us to understand its electromagnetic performance. This paper built a two-dimensional (2-D) CORC model by finite element method, and the AC losses induced by changing external magnetic field was examined. Individually, the AC loss dependence on the magnitude and frequency of the external magnetic field is examined. The results prove that the copper former will lead to an increase of the CORC cable magnetization losses in a high frequency.

This paper first introduced a conductor on round core (CORC) cable model using the finite-element method (FEM). Then, the AC loss dependent on transport current was studied, indicating the eddy current loss of the copper former. Finally, we calculated the generated loss under a simultaneous application of transport current and magnetic field, showing even a small magnetic field resulted in a significant increase in transport AC loss.

One of the High Temperature Superconducting (HTS) cables can be made by the Conductor on Round Core (CORC) structure, and it has been regarded as the reasonable option for many superconducting applications, e.g. power transmission cable and high field magnet. This article shows the simulation of superconducting CORC performed by the finite-element method (FEM) using H-formulation model, which was on the commercial platform of COMSOL. We used the 2-dimension (2D) and 3-dimension (3D) models for the superconducting CORC, and their outcomings were analyzed and compared. There were 2 design parameters in this study: (i) the gap angle, between each HTS tape, and (ii) the degree of twist: generally defined called pitch. The 2D CORC model's calculation speed was faster than 3D CORC model, but the 3D CORC model was able to simulate the loss in a realistic range.