JP2743122B2 - Superconducting rotating electric machine stator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stator for a superconducting rotary electric machine, and more particularly to a stator for a superconducting rotary electric machine adopting a gap winding method.

[0002]

2. Description of the Related Art An air gap winding type stator provided in a superconducting rotating electric machine is generally disclosed in, for example, Japanese Patent Application Laid-Open No. 58-154358.
As described in Japanese Patent Application Laid-Open Publication No. H10-209, stator teeth in the iron core slot system are all made of a non-magnetic material. That is, in the stator of the air gap winding type,
The magnetic material for magnetic shielding exists only on the outer peripheral side of the armature winding bottom surface. For this reason, the magnetic flux generated from the rotor also passes through the inside of the armature winding, causing an electromagnetic force. In particular, when the field winding is made of a superconducting material or the like, a strong magnetic field causes a strong electromagnetic force to act on the armature winding.

[0003]

As described above, in the stator employing the air-gap armature winding method, an AC magnetic field having a high magnetic flux density is directly applied to the armature winding from the superconducting field winding. For this reason, a strong electromagnetic force acts on the armature winding, and vibrations based on this electromagnetic force are also applied. Therefore, according to this winding method, there is a problem that high mechanical strength is required for each component in the armature winding body.

The present invention has been made in view of the above points, and has been made to reduce a strong electromagnetic force acting on an armature winding and to suppress vibration of an armature winding body due to the electromagnetic force. An object of the present invention is to provide a stator of a superconducting rotary electric machine capable of increasing the rigidity of a winding body itself.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a rotating armature having a stator having an air gap armature winding system in which teeth are made of a non-magnetic material and a magnetic material, and a superconducting field winding. In the stator of the superconducting rotating electric machine, the stators face each other with a predetermined gap therebetween, wherein the stator is provided between a bottom surface of the electric winding body having a large number of wires and a bottom side of the teeth portion. A bottom damper, which is a non-magnetic vibration absorbing material, is provided, and a side damper, which is a non-magnetic vibration absorbing material, provided between the side surface of the armature winding body and the teeth portion. Is provided, the teeth portion is formed by dividing the magnetic teeth made of a magnetic material arranged on the bottom side of the stator and the insulating teeth made of a non-magnetic material arranged on the rotor side of the stator,
A magnetic shield made of a ferromagnetic material is formed at a bottom portion of the magnetic tooth.

Further, a part of the teeth of the stator is made of a magnetic material. Further, an intermediate support plate is provided near the center in the axial section of the cooling pipe buried in the armature winding body.

[0007]

According to the above construction, the cross-sectional shape of the vibration-absorbing material made of a non-magnetic material buried in the bottom of the armature winding body, and the space factor and arrangement of the non-magnetic and magnetic parts constituting the teeth are provided. Can be changed to change the magnetic flux distribution near the armature winding body. Thus, the electromagnetic force acting on the armature winding can be reduced, and the radial vibration of the armature winding body based on the electromagnetic force can be suppressed.

Further, the vibration in the circumferential direction of the armature winding body is suppressed by the vibration absorbing material embedded in the boundary between the teeth and the insulating material around the armature winding.

Further, the intermediate support plate provided near the center in the axial section of the cooling pipe in the armature winding trunk has an effect of increasing the radial rigidity of the armature winding trunk.

[0010]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a partial sectional view in the axial direction of the stator of the superconducting rotary electric machine according to the present embodiment, near the armature winding body. The stator 1 is disposed to face a rotor (not shown) via a predetermined gap, and the rotor-side insulating teeth 3 and the bottom-side iron core teeth 4 are fixed via tab tails. A magnetic shield 2 made of a ferromagnetic material such as iron is formed at the bottom of the iron core teeth 4 so that magnetic flux does not leak outside the stator 1. Also, the iron core teeth 4 are provided with grooves 6 at predetermined intervals in the circumferential direction,
In the groove 6, a part of the armature winding trunk 5 and a bottom damper 7 as a vibration absorbing material are embedded.

The insulating teeth 3 are made of a non-magnetic material having high mechanical strength such as FRP (fiber reinforced plastic). The armature winding body 5 includes a small conductor 9 in which a large number of wires are bundled, a cooling pipe 10 made of a metal material having a high electric resistance such as a stainless alloy, and a ground made of a non-magnetic material having a high insulation such as mica. It is composed of an insulating material 11, a wedge 12, and the like.

The bottom damper 7 is made of a non-magnetic material having low elasticity such as special silicone rubber and having excellent heat resistance and insulation properties. Buried in At the boundary between the armature winding body 5 and the teeth 3 and 4, a side damper 8 which is a vibration absorbing material made of a non-magnetic material such as a special silicone rubber is provided like the bottom damper 7. .

Next, the operation of this embodiment will be described. By appropriately setting the length (radial length) of the iron core teeth 4,
The flow path of the magnetic flux flowing from the rotor to the stator 1 can be optimized. In other words, when the iron core teeth 4 extend to the inner diameter of the stator 1, that is, when all the teeth are made of a magnetic material, all the magnetic flux from the rotor tends to concentrate on the teeth. As a result, the magnetic flux density near the tip of the tooth greatly exceeds the saturation magnetic flux density, and iron loss increases.

Conversely, in a system called an air gap winding system, in which all the teeth are formed of a non-magnetic material, the magnetic flux flowing from the rotor to the stator 1 is formed of a ferromagnetic material such as iron. Up to the shield 2, the armature winding body 5 and the teeth, both of which are made of a non-magnetic material, are distributed almost equally in the teeth. Therefore, the conductor 9 inside the armature winding body 5
An electromagnetic force having a magnitude proportional to the product of the magnitude of the current flowing through the armature and the magnetic flux density of this portion acts on the armature winding body 5, so that the members constituting the stator have high mechanical strength. Is required.

However, in the method of using a non-magnetic material such as FRP near the tip of the teeth and using a ferromagnetic material such as iron near the root of the teeth as in the present embodiment, the armature winding body 5 has not been used. A part of the magnetic flux that has passed inside passes through the iron core teeth 4 having a higher transmittance, so that the electromagnetic force acting on the armature winding body 5 can be reduced. In addition, by adjusting the width (length in the circumferential direction) of the bottom surface damper 7 near the tooth base, it is possible to increase the cross-sectional area through which the magnetic flux passes. For this reason, the magnetic flux density in this vicinity does not exceed the saturation magnetic flux density, and the iron loss can be suppressed as small as when the air-gap armature winding method is used.

The floor damper 7 has a small elastic modulus and is easily deformed. The floor damper 7 absorbs the strain energy of the armature winding body 5 based on the electromagnetic force and converts it into heat by internal friction. In addition, the radial vibration of the armature winding trunk 5 can be attenuated. Further, since the material of the floor damper 7 is a non-magnetic material, the flow path of the magnetic flux distributed in the vicinity thereof can be optimized. That is, by changing the thickness (length in the radial direction) and width (length in the circumferential direction) of the floor surface damper 7 and forming an appropriate cross-sectional shape, the magnetic flux distribution in the vicinity of the tooth base can be changed. Therefore, a part of the magnetic flux that has passed through the inside of the armature winding trunk 5 is allowed to pass through the teeth, and the electromagnetic force acting on the armature winding trunk 5 can be reduced.

Further, since the side damper 8 is formed of a non-magnetic material, the concentration of iron loss due to the concentration of magnetic flux can be prevented. While the bottom damper suppresses radial vibration of the armature winding trunk 5 due to electromagnetic force, the side damper 8 has an effect of mainly suppressing vibration due to circumferential electromagnetic force.

As described above, in the stator of the superconducting rotating electric machine, the vicinity of the armature winding is structured as described above to optimize the flow path of the magnetic flux flowing from the rotor into the stator. Can be. This makes it possible to reduce the electromagnetic force acting on the armature winding body 5 while minimizing the iron loss due to the magnetic flux concentration, and to suppress the vibration based on this electromagnetic force.

FIG. 2 shows another embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view of the cooling pipe 10 in which an intermediate support plate 13 is provided at the center of the cooling pipe 10. According to the above-described embodiment, the electromagnetic force acting on the armature winding body 5 can be considerably reduced. Nevertheless, the strong magnetic field generated by the superconducting field winding prevents an electromagnetic force stronger than that of the conventional machine from acting. I can't. For this reason, in order to increase the radial rigidity of the armature winding body 5, a cross-sectional structure having an intermediate support plate 13 at the center of the cooling pipe 10 is adopted. With such a cross-sectional structure, first, regarding the vertical compressive force of the cooling pipe based on the radial electromagnetic force, the cross-sectional area for supporting the vertical compressive force can be increased, and the compressive stress generated inside the pipe can be reduced. . Regarding the bending of the upper and lower sides of the cooling pipe 10 due to the electromagnetic force, the bending rigidity with respect to the radial electromagnetic force is increased by increasing the number of support portions in the center.

It is conceivable that the flow rate of the refrigerant such as water flowing in the cooling pipe 10 decreases with the change of the cross-sectional structure as compared with the case where the intermediate support plate 13 is not provided, and the cooling characteristics are deteriorated. On the other hand, it is possible to improve the heat transfer coefficient by forming irregularities on the inner surface of the cooling pipe 10 and increase the heat transfer area, thereby preventing a decrease in cooling efficiency.

Further, as shown in FIG. 3, the cooling pipe 10 having the above-described cross-sectional structure has a structure divided at the intermediate support plate 13, that is, two pipes having irregularities on the inner surface are arranged in parallel. It is also possible to form.

[0023]

As described above, according to the present invention,
Since the magnetic flux flow path around the armature winding body and the teeth of the stator of the superconducting rotating electric machine can be controlled, the amount of magnetic flux from the superconducting field winding that directly acts on the armature winding can be reduced. This has the effect of reducing the electromagnetic force acting on the surface.

Further, since the buried material is also a vibration absorbing material, it has an effect of suppressing radial and circumferential vibrations of the armature winding body due to the electromagnetic force.

Further, the intermediate support plate provided inside the cooling pipe in the armature winding body has an effect of increasing the radial rigidity of the armature winding body.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing a configuration of an armature winding trunk of a superconducting rotary electric machine stator according to one embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing a configuration of a cooling pipe according to another embodiment of the present invention.

FIG. 3 is an enlarged sectional view showing another configuration of the cooling pipe.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stator 3 Insulation tooth 4 Iron core tooth 7 Bottom damper (vibration absorption material) 8 Side damper (vibration absorption material) 10 Cooling pipe 13 Intermediate support plate

Claims (2)

(57) [Claims] 1. A superconducting rotor in which a stator of an air-gap armature winding system whose teeth are made of a nonmagnetic material and a magnetic material and a rotor having a superconducting field winding are opposed to each other via a predetermined gap. In a stator of an electric machine, the stator includes a bottom damper made of a non-magnetic vibration absorbing material provided between a bottom surface of an electric winding body having a large number of wires and a bottom side of the teeth portion. And a side damper which is a nonmagnetic vibration absorbing material provided between a side surface of the armature winding body and the teeth portion, and the teeth portion is a bottom side of the stator. The magnetic teeth made of a magnetic material and the insulating teeth made of a non-magnetic material arranged on the rotor side of the stator are formed separately.
A stator for a superconducting rotary electric machine, wherein a magnetic shield made of a ferromagnetic material is formed at a bottom portion of the magnetic teeth. 2. A stator for a superconducting rotary electric machine according to claim 1, wherein an intermediate support plate is provided near a central portion in an axial section of the cooling pipe buried in the armature winding body. .