JPH0510027B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to rotating electric machines, and particularly to improvements in superconducting rotors equipped with field windings made of superconducting coils.

[Technical background of the invention and its problems]

A superconducting rotor is constructed by attaching field windings consisting of two sets of superconducting coils to the outer peripheral surface of a cylindrical torque tube. Conventionally, the ends of adjacent superconducting coils each have a connecting wire made by bundling ultra-fine superconducting wires into a single wire, and these connecting wires are twisted together or overlapped and soldered or interposed with copper or the like. They were connected using a material to form a connecting part.

This connection is also cooled with a liquid refrigerant such as liquid helium as part of the field winding, but for large-capacity devices, twisting is insufficient for electrical connection at the connection, so soldering is required. If the connection is made using a wire or an inclusion such as copper, there will be a portion of the connection that is not superconducting, and therefore heat will be generated particularly easily in this portion. Furthermore, since the magnetic field of superconducting field windings is very strong, the so-called quench phenomenon, in which the superconducting state of the connection portion is destroyed, is likely to occur under the influence of these heat and magnetic fields.

[Purpose of the invention]

An object of the present invention is to provide a highly reliable superconducting rotor that prevents the occurrence of quench by protecting the connections of superconducting coils of field windings from strong magnetic fields and preventing heat generation from the connections. It's about doing.

[Summary of the invention]

In the present invention, by covering the outer periphery of the connection part with a tube made of a superconducting material having coolant flow grooves on the outer or inner circumferential surface, lines of magnetic force from the outside are utilized by utilizing the Meissner effect and cooling effect of the tube of the superconducting material. In addition to completely blocking the
This eliminates the generation of heat and prevents the occurrence of quench.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 to 3.

The superconducting rotor is equipped with a field winding 4 consisting of two sets of superconducting coils 2 and 3 forming an N pole and an S pole on the outer circumferential surface of a cylindrical torque tube 1, and the outer circumference of the field winding 4 is a cylindrical outer circumferential plate. I'm holding it at 5. The ends of the superconducting coils 2 and 3 each have connecting wires 6 and 7 made by bundling extremely thin superconducting wires into one wire, and these connecting wires 6 and 7 are overlapped with a copper plate 8 interposed between them, The outer periphery is covered with a tube 9 made of superconducting material having coolant flow grooves on the outer or inner circumferential surface, and electrically and mechanically connected by soldering. A plurality of cooling fins 10 are provided on the outer circumferential surface of the tube 9, and the space between the fins 10 and 10 is used as a coolant circulation groove 11, and a plurality of coolant circulation grooves 11 are also formed on the inner circumferential surface of the tube 9. The field winding 4, including its connecting portions, is cooled by being immersed in liquid helium, which is a flowing coolant.

Next, the effect will be explained.

Since the field winding is in a superconducting state, a large current can flow and a strong magnetic field can be generated. This strong magnetic field is also applied to the connection part covered by the tube 9, but at this time, since the tube 9 is made of a superconducting material with coolant circulation grooves on the outer or inner circumferential surface, this is called the Meissner effect. It has the ability to strongly cut off lines of magnetic force from the outside, and no magnetic flux passes through the connection. The tube 9 has cooling fins 10 on its outer circumferential surface and refrigerant circulation grooves 1.
1, and there is also a refrigerant circulation groove 11 on the inner peripheral surface, so the connection part is strongly cooled and no heat is generated. Therefore, since no magnetic flux passes through the connecting portion and no heat is generated, quench does not occur, resulting in a highly reliable superconducting rotor.

Next, other embodiments will be described.

The embodiment shown in FIG. 4 is similar to the embodiment shown in FIG. 3, except that the refrigerant flow groove 11 on the inner peripheral surface of the tube 9 in FIG. It has an effect.

The embodiment shown in FIG. 5 is the one in which the cooling fins 10 on the outer circumferential surface of the tube 9 in FIG. 3 are eliminated, and the other parts are as in FIG. 3, and the effect is similar to that of the embodiment in FIG. There is.

It should be noted that the present invention is not limited to the embodiments described above and shown in the drawings, but can of course be implemented with various modifications without changing the gist thereof.

〔Effect of the invention〕

As explained above, according to the present invention, by covering the outer periphery of the connecting portion with a tube made of superconducting material having coolant flow grooves on the outer or inner peripheral surface, lines of magnetic force from the outside to the connecting portion can be completely prevented. Since the superconducting rotor is cut off, there is no fear of quench occurring, and a highly reliable superconducting rotor can be obtained.

[Brief explanation of drawings]

Fig. 1 is a cutaway perspective view of essential parts showing an embodiment of the superconducting rotor of the present invention, Fig. 2 is an enlarged perspective view showing the connection part of Fig. 1, and Fig. 3 is taken along the - line in Fig. 2. The enlarged cross-sectional view in the direction of arrows and FIGS. 4 and 5 are cross-sectional views showing a portion corresponding to FIG. 3 of another different embodiment. 2, 3...Superconducting coil, 4...Field winding,
6, 7... Connection wire which is the end of the coil, 9... Tube covering the connection part, 10... Fin, 11... Refrigerant distribution groove.

Claims (1)

[Claims] 1. In a superconducting rotor equipped with a field winding 4 consisting of a plurality of superconducting coils 2 and 3, a connection part is provided to connect the ends of adjacent superconducting coils 2 and 3, and the outer periphery of the connection part is attached to the outer peripheral surface or A superconducting rotor characterized in that it is covered with a tube 9 made of a superconducting material and having a coolant flow groove 11 on at least one of its inner peripheral surfaces.