A high-pinning-Type-Ⅱsuperconducting maglev for ICF target delivery:main principles,material options and demonstration models

Nowadays,inertial confinement fusion(ICF)research related to noncontact positioning and transport of free-standing cryogenic targets is playing an increasingly important role in this field.The operational principle behind these technologies is the magnetic acceleration of the levitating target carrier(or sabot)made from Type-Ⅱ,high-temperature superconductors(HTSCs).The physics of interaction among levitation,guidance and propulsion systems is based on a quantum levitation of high-pinning HTSCs in the mutually normal magnetic fields.This paper discusses current target delivery strategies and future perspectives to create different permanent magnet guideway(PMG)systems for ICF target transport with levitation.In particular,several PMG building options for optimizing both suspension and levitation of ICF targets using an HTSC-sabot will be analyzed.Credible solutions have been demonstrated for both linear and round PMGs,including the ones with a cyclotron acceleration process to realize high-running velocities of the HTSCsabot for a limited magnetic track.Focusing on physics,we describe in detail the main aspects of the PMG building and the results obtained from computations and proof of principle experiments.High-pinning HTSC magnetic levitation promises a stable and self-controlled levitation to accelerate the ICF targets placed in the HTSC-sabots up to the required injection velocities of 200 m/s and beyond.

Review on thermal-related measurement methods for superconducting devices and prospect for high-speed maglev transportation application

High‐temperature superconducting(HTS)bulks can not only be self‐stable when levitated above a permanent magnet(PM)but also can be used as quasi PM with higher magnetic energy product due to their magnetic flux pinning characteristics.Therefore,HTS bulks have wide application potentials in maglev trains,maglev bearings,flywheel energy storage,drug delivery,and high field magnets.In the external magnetic field of common application scenarios,HTS bulks have no external input current,so it is difficult to achieve the overall quench.However,local quenching in the bulk is still possible in the harsh fluctuating external field environment.Although it is difficult to reach the total quench,its critical parameters like Jc will inevitably deteriorate,which may collapse the application system.Therefore,in contrast to superconducting wires and tapes that are more concerned with quench detection,HTS bulks with a 3D volume effect are more focused on internal sensitive temperature locations,the impacts of volume and scale,and the coupling influence on application parameters such as magnetism and force.Therefore,for efficient thermal‐related measurement of HTS bulk applications,this paper investigates and discusses 12 commonly‐used temperature measurement or quench detection methods in all superconducting application fields.These methods primarily refer to the current quench detection technologies used in HTS tapes and wires.From the standpoint of practical temperature measurement requirements of HTS bulks and technological limitations of maglev application scenarios,working characteristics and service conditions of the 12 methods,and 4 temperature detection methods are selected through a comprehensive understanding and comparison of basic principles.They are expected to be used in real‐time monitoring and early warning schemes for onboard superconducting levitation devices of HTS maglev transportation or other applications in the future.