HTS Magnetic Bearings in Prototype Application

After clarifying the essential characteristics of the multiseeded YBCO bulk in the previous work, that is, the existence of strongly connected or coupled grain boundaries between two grains by means of intergrain super current with a big flowing loop size, this paper proceeds to report its achievable performance in actual excitation conditions by working as trapped-field magnets or levitation devices. Besides evaluation of the trapped-flux characteristics by two most popular excitation methods, namely, static field-cooling magnetization (FCM) and pulsed-field magnetization in liquid nitrogen (LN2), the trapped-flux capability at lower temperatures up to 30 K, an interesting temperature for present superconducting machine applications, is also reported. From LN2 temperature to 30 K, the trapped flux with over six times improvement from 0.64 to 3.91 T was observed by FCM, at the same time along with a much decreased relaxation rate from 13.7% to 0.9% in 1-h measurements. In the aspect of levitation applications, the magnetic force density (both levitation force and guidance force, two most important performance parameters for maglev) above a permanent magnet guideway with Halbach style is measured and found to be able to promote the loading and stability performance of the first high-temperature superconducting maglev test vehicle simultaneously. As the multiseeding technique of the top-seeded melt-growth process has provided a promising way to fabricate bulk superconductors with large size, time saving and cost reduction, the presented trapped-flux and magnetic force results may help to comprehend, refer, and finally make better use of the multiseeded bulks in the large-scale superconducting magnetic devices.

Section: Introductionmentioning

confidence: 99%

Trapped Flux and Levitation Properties of Multiseeded YBCO Bulks for HTS Magnetic Device Applications—Part II: Practical and Achievable Performance

Deng

Izumi

Miki

et al. 2012

“…[10], [11]. This technology feasibility has been shown successfully by others groups too [12]- [15].…”

mentioning

confidence: 73%

“…A cryostat scheme is shown in Fig. 10, and more details about the cryostats' design can be found in [10], [11]. Through this insulated line all the cryostats can be filled with a charge of liquid nitrogen.…”

Section: Liquid Nitrogen Filling Automationmentioning

confidence: 99%

A Full Scale Superconducting Magnetic Levitation (MagLev) Vehicle Operational Line

Sotelo

Oliveira

Costa

et al. 2015

154

This paper describes the construction and main components of a full-scale superconducting magnetic levitation vehicle. The prototype, comprising four 1.5-m-long wagons, will travel a short test line of 200 meters, connecting two buildings inside the campus of the Federal University of Rio de Janeiro. The efforts to implement this technology started thirteen years ago with a small-scale prototype in an attempt to prove the concept. The second step was the construction of a functional prototype that could levitate more than one Ton. The actual stage of this project is the construction of an operational prototype mentioned above, designed to transport up to 24 passengers. This work has been reported in several previous editions of the ASC conference. New details about the elevated test line, the permanent magnetic (Nd-Fe-B) guideways, the cryostats with YBCO high critical temperature superconductors, the energy conditioning, the linear induction motor and its regenerative braking, as well as the automatic supply system of liquid nitrogen will be presented in the proposed paper. Tests with this operational prototype demonstrate the technology feasibility.

“…ESEARCHERS are pursuing high temperature superconducting bearings for applications such as flywheel energy storage where low losses are critical for retaining stored energy [1], [2], [3]. Typically, these bearing systems consist of an array of permanent magnets that are stably-levitated over an array of bulk high temperature superconductors (HTSC) such as yttrium barium copper oxide (YBCO).…”

Section: Introductionmentioning

confidence: 99%

Lumped-Parameter Model to Describe Dynamic Translational Interaction for High-Temperature Superconducting Bearings

Hearn

Pratap

Chen

et al. 2014

Abstract-This paper discusses a lumped parameter modeling methodology to describe the dynamic vertical and translational force interaction between a bulk superconductor and levitated permanent magnet. The model is formulated to be easily incorporated into larger rigid body system models to aid design of superconducting bearings for flywheel energy storage applications. The proposed modeling technique will significantly reduce the computational expense in order to shorten the design cycle process. The validity of the proposed lumped parameter model is demonstrated by comparing results from Finite Element Method analysis and measurements of the force displacement interaction between a permanent magnet and bulk high temperature superconductor.