Simulations of Twin-Box Joints for ITER PF Coils

Author

Ilyin, Y. ; Rolando, G. ; Nijhuis, A. ; Simon, Felix ; Lim, B.S. ; Mitchell, Neil ; Turck, B.

Author_Institution

ITER Organ., St. Paul lez Durance, France

Volume

24

Issue

3

fYear

2014

fDate

Jun-14

Firstpage

1

Lastpage

5

Abstract

An ITER Poloidal Field coil winding consists of stacked double pancakes wound with NbTi cable-in-conduit conductors. One of the critical components of the coil is the electrical joint connecting either two conductor lengths within a double pancake or two double pancakes. All joints utilize the twin-box “shaking hands” concept. It has previously been found with the JackPot-AC numerical model that in these joints the sum of the transport and induced currents in some of the superconducting strands during coil operation may exceed the strands´ critical current. It was decided to further explore the behavior of the joint with a simplified set of current and magnetic field runs. A solution for the reduction of the induced currents is proposed and verified by modeling. The paper discusses the results of the simulations and gives recommendations for the joint design.

Keywords

critical currents; niobium alloys; superconducting cables; superconducting coils; titanium alloys; type II superconductors; windings; ITER PF coils; ITER poloidal field coil winding; NbTi; cable-in-conduit conductors; conductor length; critical components; electrical joint; joint design; magnetic field; stacked double pancakes; strand critical current; superconducting strands; twin-box joints; twin-box shaking hand concept; Coils; Conductors; Copper; Joints; Resistance; Superconducting cables; Superconducting magnets; Cable-in-conduit conductor; ITER; electromagnetic analysis; poloidal field (PF) coils; thermal analysis; twin-box joints;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/TASC.2013.2292522

Filename

6685840