High-Temperature Superconducting Non-Insulation Closed-Loop Coils for Electro-Dynamic Suspension System

Round 1

Reviewer 1 Report

This paper presents a high temperature superconducting (HTS) no-insulation closed-loop coils applied for electro-dynamic suspension (EDS) system and energized with persistent current switch. This paper is well written with sufficient analysis. This paper can be considered for acceptance if the authors can address the following issues.

1. The introduction can be improved. The benefits of EDS over other suspension technologies such as EMS and high temperature superconducting flux pining suspension can be extended. 

2. Can the authors develop a little bit more about the choice of using double-pancake module?

3. Regarding the finite element analysis results, I am curious about the magnetic model used in this simulation, can the authors extend further on this please ?

4. Figure 20 is hard to appreciate (mainly the inset), please embellish this figure.

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

This paper has designed no-insulation HTS closed-loop coils which can be potentially applied to EDS maglev systems. The coil performance energized by a persistent current switch has been studied through FEM based numerical modelling and experimental measurements.

I have some comments for the authors to consider, as follows:

1) How to determine the discount factor k?

2) How did you carry out your simulation? I assume that the Jc(B, theta) dependence has been implemented into COMSOL. Please provide more details regarding the modelling approach so that the readers are able to reproduce the relevant results.

3) How do you account for the discrepancy in terms of load factor distributions in distinct coils, as shown in Figure 10? You can consider the shielding effect between different turns
(https://iopscience.iop.org/article/10.1088/1361-6668/ab9ace for your reference).

4) Please illuminate the fast rise of the joint resistance ai higher currents in Figure 19.

5) How to keep the cryogenic environment for the superconducting magnets in offline operation?
With what kind of thermal insulation?

6) The English writing level needs to be improved throughout the manuscript to a large extent.
There exist lots of typos in the paper, e.g., “in the persistent current mode” (rather than “model”) in Abstract, Lines 49, 57, 89, 116, 144 (two middle/central etc), 208 (be fully saturated), Figure 17 (loop current), etc. In table 1, the unit for single pole dimensions should be mm3?

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

The authors have well sorted out my questions. Thanks!

Author Response

Dear reviewer:
We are very grateful to your comments and advice for the manuscript.