Winding former for a saddle coil winding
A winding former with a winding support between a first plate and a second plate for a saddle coil winding made up from a thin layer HTSC, which is destined for a cylindrical armature of an electrical machine, and which has two longitudinal legs parallel to the armature axis between two winding ends, wherein the winding support for each winding end has a bearing surface, which enables the thin layer HTSC to be wound to form a saddle coil without damaging the HTSC thin layer.
1. A winding former for a high temperature superconductor (HTSC) saddle coil winding disposed on a cylindrical armature of an electrical machine, the armature having an armature circumference and an armature axis, the winding former comprising:
a HTSC saddle coil winding formed from band-shaped HTSC, the saddle coil winding including:
a first winding end,
a second winding end, and
two longitudinal legs disposed between the winding ends, wherein the longitudinal legs are oriented parallel to the armature axis;
a first plate disposed under the HTSC saddle coil winding and a second plate disposed over the HTSC saddle coil winding; and
a winding support oriented between the first plate and the second plate, wherein the winding support has a bearing surface for each winding end,
wherein the first plate and the second plate comprise hollow cylinder segments shaped to match to the armature circumference in the region of the longitudinal legs, and wherein each bearing surface for a respective winding end is twisted such that a maximum distance (d o ) separating upper edges of the bearing surfaces measured parallel to a cylinder axis is smaller than a maximum distance (d u ) separating lower edges of the bearing surfaces measured parallel to the cylinder axis.
2. The winding former according to claim 1 , the first and second plates are concentric with one another, at least in the region of the longitudinal legs.
3. The winding former according to claim 1 , wherein:
the winding former further comprises bearing surfaces for the longitudinal legs; and
at least one of the longitudinal leg bearing surfaces is twisted in at least one region such that magnetic flux through narrow faces of the band-shaped HTSC in the twisted region becomes a maximum when, by a rotation of the armature, the longitudinal leg is brought into the region in which the magnetic flux density of the external magnetic field acting on the armature is a maximum.
4. The winding former according claim 1 , wherein each plate in the region of the longitudinal legs of the saddle coil winding includes a projection beyond the corresponding longitudinal leg.
5. The winding former according to claim 4 , wherein:
the plates in the region of the projections have grooves opposing one another; and
at least one supporting element operable to laterally constrain the saddle coil winding is positioned within the opposed grooves.
6. The winding former according to claim 1 , wherein the winding former in the region of each longitudinal leg of the saddle coil winding has a longitudinal strut, which, in cooperating with two longitudinal edges, abuts against the first plate.
7. The winding former according to claim 1 , wherein:
the winding former in the region of each longitudinal leg of the saddle coil winding comprises a longitudinal strut with an upper face including two longitudinal edges; and
the second plate abuts the two longitudinal edges.
8. The winding former according to claim 1 , wherein the winding support comprises a closed metal band having narrow faces, wherein one of the narrow faces of the metal band abuts against the surface of the first plate.
9. The winding former according to claim 8 , wherein the surface of the first plate is coupled to an inner face of the metal band via a strut.