13 research outputs found
Screening Current-Induced Field and Field Drift Study in HTS coils using T-A homogenous model
The emergence of second generation (2G) high-temperature superconductor (HTS)
tapes has favored the development of HTS magnets for their applications in
areas such as NMR, MRI and high field magnets. The screening current-induced
field and the field drift are two major problems hindering the use of HTS tapes
in the mentioned areas. Both problems are caused by the screening current, then
it is necessary to have a modeling strategy capable to estimate such phenomena.
Thus far, the H formulation has been the most successful and used approach to
model medium-size systems (hundreds of tapes). However, its application to
large-scale systems is still impaired by excessive computation times and memory
requirements. Homogenization and multi-scaling strategies have been
successfully implemented to increase the computational efficiency. In this
contribution, we show that using the homogenization technique with the recently
developed T-A formulation allows reducing the computation time and the amount
of memory up to the point that real-time simulations of slow ramping cycles of
large-scale systems are possible. The T-A homogeneous model also allows
systematically investigating the screening current using numerical simulations
Optimization of the Superconducting Linear Magnetic Bearing of a Maglev Vehicle
Considering the need for cost/performance prediction and optimization of
superconducting maglev vehicles, we develop and validate here a 3D finite
element model to simulate superconducting linear magnetic bearings. Then we
reduce the 3D model to a 2D model in order to decrease the computing time. This
allows us to perform in a reasonable time a stochastic optimization considering
the superconductor properties and the vehicle operation. We look for the
permanent magnet guideway geometry that minimizes the cost and maximizes the
lateral force during a displacement sequence, with a constraint on the minimum
levitation force. The displacement sequence reproduces a regular maglev vehicle
operation with both vertical and lateral movements. For the sake of comparison,
our reference is the SupraTrans prototype bearing. The results of the
optimization suggest that the bearing cost could be substantially reduced,
while keeping the same performances as the initial design. Alternatively, the
performances could be significantly improved for the same original cost