March 05, 2020

Shielding current analysis of axisymmetric high-temperature superconducting film by using equivalent-circuit model.

SOKENDAI Student Dispatch Program program year: 2019

YAMAGUCHI Takazumi, Fusion Science

A schematic view of the SLA system (upper figure) and the ECM (lower figure): The SLA system accelerates a pellet container by the electromagnetic force acting on an HTS film. Electromagnetic properties of the SLA system are approximated as the ECM composed of an electromagnet and a set of HTS loops.

The brief description

In order to generate and maintain a plasma, a fuel pellet is injected into the plasma. Recently, a superconducting linear acceleration (SLA) system has been proposed as a pellet injection system. However, the acceleration performance of the SLA system is not clear because the SLA experiment has not yet been performed. Therefore, it is necessary for the development of the SLA system to investigate the acceleration performance numerically. The purpose of the present study is to investigate the acceleration performance by using the equivalent-circuit model (ECM).

In the present study, the distribution of the shielding current flowing in a high-temperature superconducting (HTS) film is approximated as a set of HTS loops. Namely, the current distribution is regarded as the electrical circuit which is composed of the electromagnet and the HTS wires. The results of the present study showed that the mass of the HTS film can be reduced to 40% with keeping the acceleration performance.

The present study contributes the development of the SLA system. In the future work, properties of the electric current flowing in the electromagnet will be optimized so as to realize the advanced improvement of the acceleration performance.


A) Place and period of my visit
COMPUMAG 2019, the 22nd International Conference on the Computation of Electromagnetic Fields, carried out in the Campus Pierre and Marie Curie of Sorbonne University (Paris, France), July 15-19, 2019.

B) What you learned and archived during the visit
I was able to gather the information about a numerical method for electromagnetic-field analysis. Especially, an oral and poster presentation about optimization technique was useful for my future work. Also, I discussed the analysis of the shielding current in the HTS with overseas researchers and received useful advice from the researchers. I was able to get some motivation by attending this conference.

Department of Fusion Science, Takazumi YAMAGUCHI