JPS61247267A - Superconducting rotary electric machine - Google Patents

Abstract

PURPOSE:To eliminate leakage liquid of a cooling pipe and improve reliability, by transferring the insulating fine wires of coil wires and the coil wires, and by insulating the cooling pipe from the insulating fine wires. CONSTITUTION:A rotor 2 with superconductive field windings contained in the stator frame 1 of a superconducting rotary electric machine is supported by a bearing 3, and the periphery via space 4 is provided with armature coils 5 supported by a stator core 6. The coils 5 are formed by connecting the both ends of the half turn upper coil 5a and lower coil 5b together with clips 7 as specified, and on the periphery of the cooling pipe extended outside the coil ends, the first transfers of seven units are fitted ad formed by using the fine wires for formal insulation, and coils wires are produced to be wound up with insulating tapes. By using a plurality of the wires, desired coils 5 for the second mutual transfers are produced. Then, the respective wire ends of coil end sections are integrally formed, and the clips 7 are silver-soldered. Besides, a sleeve is fitted on the end section of the cooling pipe 9, which is liquid- tight seal welded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a superconducting rotating electric machine in which a half-turn coil of an armature winding is improved.

[Technical background of the invention and its problems]

As a means of increasing the capacity of a single rotary machine and improving efficiency, the armature winding, which was conventionally housed in the slots of the stator core, has been replaced with a shielding stator core without slots and a superconducting field winding. Superconducting rotating electric machines have come to be used which include a gap armature winding arranged in a gap between the built-in rotor and a gap armature winding fixed to a stator core.

The armature winding placed in the air gap naturally has no teeth since there are no slots in the stator core.

When directly exposed to the strong magnetic field from the rotor, the coil conductors that make up the armature windings suffer from large eddy current losses, which makes them difficult to match with conventional coils housed in the stator core slots. Differently, bundled wire was used, which was made by twisting and bundling thin formal-insulated wires with a diameter of about 1 inch. This cooling means for the wire bundle is as described in Japanese Patent Application Laid-Open No. 58-218845.

Some devices provide cooling by placing cooling pipes between the wire bundles. However, in this case, the wire bundle and the cooling pipe are arranged side by side and transposed to each other, so it is not possible to cool the strands on the insulated side.

Something even more powerful was desired. Also, make sure that the cooling pipes themselves do not suffer from eddy currents.

A metal 1, such as stainless steel, is used, which has a higher electric resistivity than copper, which is the material of the armature coil. For this reason, even if you try to connect the cooling path at the same time as the electrical path as in the past,
Reliable silver brazing was difficult due to the inclusion of different materials such as stainless steel pipes and the extremely large number of thin insulated wires.On the other hand, the electrical constants of the electric circuit as an armature winding Among the resistance and actance, the reactance value is dominant, so the armature current that flows in both electric circuits is restricted by the reactance. This means that if a half-turn coil consisting of a stainless steel cooling pipe and an insulated wire is electrically connected at both ends, a current corresponding to the reactance will also flow in the cooling pipe, which has a higher electrical resistivity than the coil conductor. The greater the flow and specific resistance, the greater the resistance loss in the cooling pipe.

This has the drawback of reducing the efficiency of the rotating electric machine and significantly reducing the cooling effect.

[Purpose of the invention]

The present invention provides an armature winding using a half-turn coil that eliminates liquid leakage from the cooling liquid flow path of the armature winding, provides high reliability, and reduces resistance loss due to circulating current in the cooling pipe. The purpose of the present invention is to provide a superconducting rotating electric machine having the following features.

[Summary of the invention]

In the present invention, a rotor having a superconducting field winding,
A shielding stator core without slots is placed around the stator core with a gap in between, and a plurality of half-turn coils placed in the gap and fixed to the stator core are connected in a predetermined manner to form an armature winding. In a superconducting rotating electric machine, a half-turn coil is formed by winding a plurality of insulated wires with a first transposition around a cooling pipe extending outward from the end of the coil to form a coil bundle. A desired half-turn coil is obtained by using a plurality of bundled wires and performing a second transposition with each other, and the end of this half-turn coil is connected to a Hiji conductor that connects between the upper and lower half-turn coils or between the coil and external wiring. At the same time, an electrical insulating layer is provided on the surface facing the cooling pipes, and the cooling pipes are bundled into coils and sleeves are fitted on them. The gap at the end of the coil is made liquid-tight by arc welding and connected to the coolant distribution member, and the insulated wire of the coil bundle is not only transposed.

Furthermore, the coil bundle wires are also transposed to make the characteristics of the armature windings uniform both above and below in a strong magnetic field, and by insulating the cooling pipe from the insulated wires, resistance loss due to circulating current is reduced. It has decreased to close to 0. Furthermore, the end surface of the cooling pipe was also made liquid-tight.

This eliminates leakage and improves reliability.

[Embodiments of the invention]

Embodiment 1 Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 to 6.

In FIG. 1, ``■'' is a stator frame of a superconducting rotating electric machine, and within this stator frame ``■'' a rotor ``■'' in which a superconducting field winding (not shown) is housed'' is supported by a bearing ``■''. The armature coil (2) is supported by the stator core (0) on the outside of the armature coil (2) via an air gap around it.

This stator core 0 has no slots (therefore no teeth) and is used for magnetic shielding. Armature coil ■
are the half-turn upper coil (5a) and lower coil (5,)
Make the specified connections at both ends with clips (■) to form the armature winding.

As shown in Figures 2 to 5, the half-turn coil ■ has formal insulation with a diameter of approximately 1 m around the cooling pipe ■ for passing liquid (generally using water) that extends outward from the coil end (5 degrees). Seven pairs of first transpositions (also referred to as transpositions) are attached using seven side wires (C), and this is compression-molded into a rectangular cross section to make a coil bundle (10), which is insulated. Wrap the tape (11). This coil bundle wire (1
A desired half-turn coil (2) is made by mutually performing a second transposition using a plurality of coils (2). At this time, when the insulating tape (11) at the end of the coil is peeled off and silver soldering is applied, the formal insulating layer of the side strand (2) disappears, and the ends of each strand (2) become integrated. The clip ■ is silver-soldered to this, and the electrical insulation layer (9a) made of ceramic spraying is placed on the opposite surface of the cooling pipe ■ (make it a little longer to allow for extra space).
, and insulate the coil (■) from the cooling pipe. The length of the clip ■ should be at least 6 times the first transposition pitch of the coil bundle wire (10), and the upper and lower coils (5a) = (5b
) A conductive filler (78) is interposed in the gap between the two.

The lead conductor part (not shown) that connects the external wiring of the coils (sa) and (5b) is fixed to the specified position by brazing a correspondingly sized clip (not shown) using the same method as above. Make the connection.

The cooling pipes (10) extending from the coil bundle wire (10) are bundled together for each coil, and a sleeve (12) is fitted to the end to connect the cooling pipes (10) to each other and the cooling pipes (10). The end face of the gap between the pipe (9) and the sleeve (12) is liquid-tightly sealed and welded. An elbow (13) is welded to the outside of the sleeve (12), and the elbow (13) attached to the upper and lower cooling pipes is connected to a ceramic connecting pipe (14).
and silver solder. A liquid supply header (16) and a liquid drainage header (17) are connected to the sleeve (12) of the liquid supply/drainage section by a connecting pipe (18) (see Fig. 1). In addition, the above elbow (13).

The connecting pipe (14) will be referred to as a liquid supply header (16), a liquid discharge header (17), a connecting pipe (18), etc. will be referred to as a cooling liquid distribution member (15).

Next, the effect will be explained.

Although the coil bundle wire (10) has a large cross-sectional area, seven incomplete insulated mesh wires (■) each having undergone the first transposition are collected and attached around the cooling pipe, and the cross-sectional area is Since the second transposition is carried out using a plurality of coil bundle wires (io) which are compression-molded into a rectangular shape and wrapped with insulating tape (11), the current in each insulating mesh wire is small even in one strong magnetic field. Density averages out.

Therefore, there is no need to increase the cross-sectional area of the half-turn coil unnecessarily. Since the cooling pipe (1) is arranged at the center of each coil bundle (10), the cooling efficiency is good. Each cooling pipe ■ has an electrically insulating layer (9a
), electrical insulation is formed from the bare conductor at the connection part of the half-turn coil ■, and the upper and lower coils (sa)
, (sb) cooling pipe is a ceramic connecting pipe (14
), the circulating current through the cooling pipe (2) can be brought close to zero. Since the cooling pipe extends outward from the coil (2) and is connected to the cooling fluid distribution member in a liquid-tight manner, there is almost no leakage and reliability is improved. Further, since the insulating mesh wire is a formal wire, the formal coating of that part is automatically peeled off by the high temperature of silver brazing, making brazing easier and reducing the number of man-hours. Moreover, since the fluid connection is made on the outside of the clip (1) in the axial direction, it is easy to work with, and even in the unlikely event of fluid leakage, there is no need to disassemble the electrical connection part, which has the advantage of being easy to maintain.

Embodiment 2 FIGS. 7 and 8 show the main parts of the second embodiment. In this embodiment, the cooling pipe (■) is bent into an elbow shape and connected with a facing connection pipe (14). The rest is the same as in Example 1.

In this way, the elbow can be omitted and the same effects as in the first embodiment can be obtained.

Example 3 FIGS. 9(a) and 9(b) show the main parts of the third embodiment.

This is characterized in that when the coil bundle wire (10) is made, the cooling pipe (2) is formed from a circular cross section into a rectangular shape, and the other features are the same as in Example 1.

Even in this case, the same effects as in the first embodiment can be obtained.

〔Effect of the invention〕

As explained above, according to the present invention, the current density of the insulated mesh wire of each coil is equalized, leakage from the cooling liquid flow path of the armature winding is eliminated, and high reliability is achieved. Moreover, it is possible to provide a superconducting rotating electrical machine having an armature winding that reduces resistance loss due to circulating current in the cooling pipe.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view of the upper half of a first embodiment of the superconducting rotating electric machine of the present invention, FIG. FIGS. 4(a) and 4(b) are a partial cross-sectional layout view and an end view showing the shape of the coil bundle shown in FIG. 1 before and after compression molding; FIG. 5 is a perspective view of a main part showing an electrical insulating layer of the cooling pipe of FIG. 1, and FIG. 6 is an end view showing a joint portion of the cooling pipe. FIG. 7 is a partially cutaway elevational view showing the main parts of the second embodiment, FIG. 8 is a cross-sectional side view taken along the line ■-■ in FIG. 7, and FIG.
a) and (b) are a partial cross-sectional layout view and an end view showing the shape of the coil bundle wire of the third embodiment before and after compression molding. 2...Superconducting rotor 4...Gap 5...Coil 5a...Upper coil 5b...Lower coil
6... Stator core 7... Clip 8
...Insulated mesh wire 9...Cooling pipe 9a...
Electrical insulating layer 10...Coil bundle wire 11...Insulating tape 12...Sleeve 15...Cooling fluid distribution member 13.14, 16, 17, 1g...Parts agent for cooling fluid distribution member Patent attorney Mr. Inoue - Male Figure 2 Figure 6 Figure 8 Figure 7

Claims (3)

[Claims] (1) A rotor having a superconducting field winding, a shielding stator core without slots arranged around the rotor through an air gap, and a shielding stator core arranged in the air gap and fixed to the stator core. In a superconducting rotating electrical machine in which a plurality of half-turn coils are connected to each other as an armature winding, the half-turn coil has a plurality of thin insulated wires arranged around a cooling pipe extending outward from the end of the coil. A plurality of these coil bundles are used to perform a second transposition with each other to form a desired half-turn coil, and the ends of this half-turn coil are connected to the upper and lower half-turn coils. An electrical connection is made by silver brazing by fitting a clip between the coil and the output conductor that connects the coil and the external wiring, and an electrical insulating layer is provided on the surface facing the cooling pipe to be brazed. A superconducting rotating electric machine characterized in that the cooling pipes are bundled into coils and fitted with sleeves, the gaps between their end faces are made liquid-tight by arc welding, and connected to a cooling fluid distribution member. (2) The insulated wire of the coil bundle is formal insulated copper wire.
2. A superconducting rotating electric machine according to claim 1, wherein the coil ends are connected using clips having an axial length of six times or more the first dislocation pitch using real stranded wires. (3) Claim 1, characterized in that the electrical insulation layer of the cooling pipe is formed by ceramic spraying.
The superconducting rotating electric machine according to item 1 or 2.