AC loss will cause the superconducting device's temperature rise, affecting the economics of the corresponding cryogenic system. To support the application of CORC cables for high-field magnets and power transmission, this paper investigates the AC loss of bent CORC cables by experiments and simulation. First, integrating a high-resolution CORC cable bending tool, a measurement platform was constructed to test the cable's I _c and AC loss. Then, to illustrate the experimental results, the geometric model of bent CORC cables was built by the pre-processing software, which is based on the cabling and bending models. Further, considering the shell characteristics of the geometric model, the efficient T-A formulation was introduced to analyze the electromagnetic performance. Finally, according to the cable specifications, the transport AC loss of bent CORC cables was investigated through parametric study. As the bending curvature increases, the AC losses of the CORC cable initially decrease and then increase. In conclusion, the modelling method proposed in this paper not only guides the optimal design of bent CORC cables, but also serves for the construction of other nonanalytic geometric models.

Compared with the traditional cable, the high-temperature superconducting (HTS) cable has the advantages of low loss and large capacity transmission. At present, the research on HTS cables mainly focuses on the calculation of AC loss, the performance under specific working conditions and cooling system design. Relatively little research has been carried out on the basic design and overall layout optimization of the cables. In this paper, an HTS cable with a rated current of 4 kA was designed. Firstly, according to the selected superconducting cable parameters, the body design of cables with different structures was carried out and the corresponding finite element models were built. Then, the performance analysis of HTS cables with different layouts was carried out based on the proposed cable performance evaluation indicators and the CORC double-layer structure was determined as the scheme of this cable. Finally, the AC loss of the cable with this topology was calculated to be 9.81 J/m under rated conditions. The cooling system can ensure the safe operation of the cable in the rated temperature range.

For a 2.4 MW high-temperature superconducting (HTS) motor, a rotating cold mass support with good strength and stiffness was required. In this research, arch-shaped support was ultimately suggested by the good performance of strength, deformation, thermal leakage, and manufacturability. The arch-shaped support, which was made of Glass-Fiber Reinforced Plastic (GFRP), had a good capability for resisting multiple physical field loads and heat insulation at the same time. Tests were carried out and proved that the compressive strength of the support could reach 322.85 MPa and the average coefficient of thermal conductivity of the support was less than 0.43W/(m•K) at room temperature. According to the results of the stress and deformation study, the tangential deformation of the arch support won't significantly vary when the direction of rotation changes. Additionally, when electromagnetic and thermal loads were introduced, arch support performed better at resisting radial and tangential deflection, which was beneficial for maintaining the electromagnetic and mechanical environment of the motor and safeguarding HTS magnets.

REBCO coil is a promising technology for superconducting magnetic energy storage system (SMES). Although degradation has been discovered in epoxy impregnated coil, it is essential to fill the coil with epoxy in such occasion. This paper describes preparation of large scale epoxy impregnated REBCO coil for SMES. The coil with inner diameter 320 mm and 268 turns was tested at 77 K both before and after epoxy impregnation. Consistency of Ic value and high n-value suggest that there was no degradation in the coil. Conduction cooled test was also carried out. Transport current was run up to 223 A at 50 K.

High-temperature superconducting (HTS) coil magnets possess extremely high quality factors, therefore having unique advantages when applied to wireless power transfer (WPT) systems especially under low-frequency conditions. The dependence of peak output power and transfer efficiency of an HTS WPT system on the operating frequency varies with the design of the coils because the structure of the coils significantly affects the resonant frequency and ac loss of the HTS WPT system. In this work, a high-power HTS WPT system, including the transfer characteristics under different coil structures, current-carrying conditions, and operating frequencies, has been investigated based on the finite-element simulation to find the optimized operating frequency band and coil structure. It has been found that the change of the inner radius and turn gap in both the solenoid and pancake coils induces a predictable transition frequency change. As the gap is varied, the transfer efficiency remains relatively constant for both coil types. However, for solenoids, reducing the gap value enhances the transferred power, whereas for pancake coils, increasing the gap value augments the transferred power. A transfer efficiency as high as 98.86% or more can be achieved under the optimal conditions.

Flux pumps can be exploited to energize superconducting coils without physical contacts, making them an attractive option for practical applications such as closed loop magnets. However, the physical mechanism of the dynamo -type flux pump has yet to be fully understood. This paper investigated the effect of pinning performance on the open-circuit voltage ( $ V_{oc}$ ) of a dynamo -type flux pump. We conducted experiments to measure and compare the $ V_{oc}$ induced in high temperature superconducting (HTS) tapes prepared using Metal-organic Deposition (MOD) and Metal-organic Chemical Vapor Deposition (MOCVD), as well as in MOD tapes with varying doping levels of BZO nano-particles. We found that HTS tapes with lower flux pinning potential exhibited higher $ V_{oc}$ . Additionally, we employed a two-dimensional numerical model based on the coupled $\mathbf{H}$ - $\mathbf{A}$ formulation to reproduce the experimental results. The rectification behavior during the dynamical process has been realized with the model and the influence of flux pinning related parameters discussed. These outcomes can serve as a guide for the device enhancement.