Powering Multi-Coil Systems Combining DC and Pulsed Power Supplies

Abstract

The highest non-destructive fields are provided by pulsed field magnets. Monolithic coils are limited to 70-75 Tesla by mechanical and thermal constraints. These limitations can be circumvented through the use of multi-coil assemblies.At HFML, pulsed field magnets can be energized using either a 2 MJ, 16 kV capacitor bank or a state-of-the-art 20 MW DC power supply in pulsed mode; each of these sources is capable of delivering up to 20 kA. This would allow multi-coil operation at fields to above 80 T.

Optimization of Large Multiple Coil Systems for Pulsed Magnets

“…For the power-limited generator of HFML in Nijmegen [4], one can start with an optimally power-efficient outer-coil design, κ = α/β = 2a 2 /h ≈ 1.66, and accommodate the 2 MJ energy of the capacitor bank for the inner coil. The low voltage of the 20 MW power converter was a limiting factor (because the maximum conductor section that can be obtained and wound is limited) with outer coils becoming large (a 1 > 110 mm) but low field (25-30 T), and the maximum attainable fields in 20 mm bore will therefore not exceed 80 T.…”

The Pulsed-Field Facility at HFML, Commissioning and First Results

“…In the next step, a new sample carrier was designed to minimize pick-up effects; measurements were successfully performed at 1.6 K and 4.2 K on a similar 2DES double quantum well as used in [10], using currents of [1][2][3][4][5][6][7][8][9][10] . The results will be reported elsewhere.…”

“…As a unique feature, the two power supplies can be combined to energize a pair of nested coils to extend the available field range well beyond 75-80 T [3]. More details on this feature can be found elsewhere [4].…”