Persistent current mode operation of a second generation (2G) high temperature superconducting (HTS) magnet is one of the bottleneck techniques for an HTS NMR or MRI applications. In order to realize the persistent current mode in the HTS magnet, the authors had proposed the concept of joint-less winding method with 2G HTS wide conductors and verified successfully that it could maintain...
This paper describes an analytical method to predict undesirable magnetic field inhomogeneity caused by manufacturing errors and evaluation of the permissible manufacturing tolerance for a high temperature superconductor (HTS) NMR magnet. Recently, HTS magnets have been actively studied for high-field nuclear magnetic resonance (NMR) (>1 GHz) magnet worldwide. Most high-field HTS magnet wound...
We present construction and test results of Coils 2 and 3 of a 3-nested-coil 800-MHz (18.8 T) REBCO insert (H800) for the MIT 1.3-GHz LTS/HTS NMR magnet currently under construction. Each of the 3-nested H800 coils is a stack of no-insulation REBCO double-pancakes (DPs). The innermost 8.7-T Coil 1 (26 DPs) was completed in 2016; the middle 5.7-T Coil 2 (32 DPs) has been fully assembled and...
This paper presents design and implementation of ferromagnetic shims for a conduction-cooled 3-T 100 mm winding diameter no-insulation (NI) all-REBCO magnet. The initial magnetic field profile was measured by an in-house 3-D field mapper with an NMR magnetometer, from which harmonic coefficients up to 3 order are derived. A ferromagnetic shim design code was developed, which includes an...
We are starting the development of a persistent 400 MHz (9.39 T) LTS/REBCO NMR magnet as a first step towards a 1.3 GHz (30.5 T) LTS/HTS NMR. The 400 MHz magnet consists of a layer-wound REBCO innermost coil and an LTS outer coil which are operated in individual persistent circuits. The system requires the following technical developments; (a) a REBCO-REBCO superconducting joint, located above...
The unique magnets for compact NMR relaxometry device consisted of the stacked high temperature superconducting (HTS) bulk annuli trapped by a field cooling (FC) method are suggested and studied. The magnetically charged HTS bulk magnet for NMR relaxometry device is cooled by liquid nitrogen and no more need a power supply. The strength and homogeneity of the magnetic field required for the...
In this paper we present design, construction, and preliminary test results of a proof-of-concept (POC) prototype, high-temperature superconductor (HTS) shim coils energized, for the first time ever, by a flux pump. For high-resolution NMR spectroscopy the spatial magnetic field must be uniform to within <0.1 ppm over a given region of interest (ROI). Field shimming is indispensable for...
In order to developing the nuclear magnetic resonance (NMR) superconducting magnet and other applications, a series of high field magnet manufacture technologies are researching in our institute, IEE CAS. The Nb3Sn superconductor is indispensable for the 500 MHz and above NMR magnet. In this paper, a dynamic vacuum pressure impregnation (VPI) process of Nb3Sn coil on the basis of Darcy’s law...
A new proton therapy scanning system for the treatment of can-cer has been accomplished at the Shanghai Institute of Applied Physics (SINAP/China). It is mainly comprised of two separate dipole magnets, each controlling horizontal and vertical direc-tions scanning independently. According to the design require-ments, we have confirmed the dimensions of the magnets and op-timized the local and...
