JPH04105547A - Rotor of superconducting rotary electric apparatus - Google Patents

Abstract

PURPOSE:To obtain the rotor of a superconducting rotative electric apparatus capable of decreasing vibration caused by the anisotropy of the rigidity of a coil fixation shaft without decreasing the rigidity by arranging a flexible support having two elastic main axes of different rigidity on a plane intersecting the rotation central axis of the coil fixation shaft. CONSTITUTION:The rigidity in the direction of the X-axis of a flexible support 20 to support a coil fixation shaft 6 is greater than its rigidity in the direction of the Y-axis. Therefore, when the flexible support 20, which has two elastic main axes of different rigidity, is arranged with its high-rigidity X-axis at the slot side of the coil fixation shaft 6 and its low-rigidity Y-axis at the magnetic pole side of the coil fixation shaft 6, the anisotropy of the rigidity of the coil fixation shaft 6 is cancelled and that of the whole rotor is decreased. Therefore, vibration caused by the anisotropy of the rigidity of the coil fixation shaft 6 is decreased without decreasing its rigidity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Field of Industrial Application) The present invention relates to a rotor for a superconducting rotating electric machine.

(Prior Art) In recent years, so-called superconducting rotating electric machines that utilize superconducting conductors as field windings of rotors have been developed.

The rotor of this type of rotating electrical machine (hereinafter referred to as a superconducting rotor) is constructed as shown in FIG. It is attached with its axial center line aligned with the axial center line of the room temperature damper 1. Each of these rotating shafts 2.3 is supported by a bearing 4, and a flange 5 is provided at an end of the rotating shaft 2 to be connected to a drive source such as a turbine (not shown).

Further, the normal temperature damper 1 also serves as a vacuum container, and a shaft 6 for mounting a coil is housed inside the vacuum container. In this coil installation, the shaft 6 is for holding the superconducting field coil 7, and the surface thereof has a plurality of slots 8 (see Fig. 10).
However, the coil attachment is formed along the axial direction of the shaft 6.

These slots 8 have a so-called saddle shape, and a superconducting conductor forming the superconducting field coil 7 is housed inside the slots 8 .

Further, in the case of mounting the coil, the shaft 6 is hollow in the center, and liquid helium 9 as a refrigerant is accommodated in the hollow part. This liquid helium 9 is superconducting field coil 7
The refrigerant is supplied through a refrigerant supply pipe 11 from a refrigerant supply/discharge device 10 provided at the end of the rotating shaft 3. Note that a collector ring 13 is provided at the end of the rotating shaft 3 to supply a field current to the superconducting field coil 7 via a current lead 12.

In addition, in the coil installation, the shaft 6 is supported approximately at the center of the normal temperature damper 1 by a torque tube 14 and a flexible support 15. The torque tube 14 is used to transmit the rotation of the rotary shaft 2.3 to the shaft 6, and the coil is installed between one end of the shaft 6 and the end of the normal temperature damper 1. The flexible support 15 is designed to absorb the difference in thermal contraction between the room temperature damper 1 and the shaft 6, and the coil is mounted between the outer periphery of the end of the shaft 6 and the inner peripheral surface of the room temperature damper 1. It is provided. In addition,
The flexible support 15 is formed from a circular thin plate so that the coil can be easily bent in the axial direction of the shaft 6. In addition, in the above-mentioned coil installation, a radiation shield 16 is provided on the outer periphery of the shaft 6 through a space, and this radiation shield 16
This prevents heat from entering from outside.

In the superconducting rotor configured as described above, the superconducting field coil 7 is cooled to an extremely low temperature by liquid helium 9, and the superconducting field coil is connected to the current lead 12 from the collector ring 13 provided at the end of the rotating shaft 3. When a field current is applied to the superconducting field coil 7, the superconducting field coil 7 becomes a permanent magnet and generates a strong magnetic field. Therefore, by rotating the rotor while maintaining the superconducting state of the superconducting field coil 7, alternating current power can be generated in a stator (not shown) disposed around the room temperature damper 1.

By the way, in the superconducting rotor as described above, when the superconducting field coil 7 has a two-pole configuration, the coil mounting shaft 6 has a cross-sectional shape as shown in FIG. When mounting a coil with such a cross-sectional shape, the shaft 6 has different rigidity in the X-axis direction and the Y-axis direction, which are orthogonal to each other, and the coil mounting has different rigidity in the Y-axis direction due to the effect of the slot 8 formed on the surface of the shaft 6. is larger than the bending rigidity in the X-axis direction.

A rotating shaft with two elastic principal axes with different stiffnesses is generally called an anisotropic rotating shaft, and if the anisotropic rotating shaft is supported horizontally, the Since the deflection varies depending on the rotation angle of the rotating shaft, the anisotropic rotating shaft vibrates at a frequency twice the number of rotations. In addition, when an anisotropic rotating shaft is rotated at the bending natural frequency of 172, the excitation based on the anisotropy of the shaft stiffness and the bending natural frequency match, causing resonance called a secondary critical speed. Phenomena also occur.

Such a vibration phenomenon caused by an anisotropic rotating shaft is a problem not only in the rotor of a superconducting rotating electric machine but also common in conventional two-pole turbine generators, that is, normally conducting rotors. As a means to solve this problem, in conventional two-pole turbine generators, for example, as shown in FIG. There are known methods of reducing the anisotropy of rigidity, or by providing grooves 18 called cross slots in the magnetic pole part at appropriate intervals in the axial direction, as shown in FIG. There is.

(Problems to be Solved by the Invention) However, when these techniques are applied to a superconducting rotating electric machine, the following problems occur.

That is, in a superconducting rotating electrical machine, the strength of supporting and fixing the superconducting field coil 7 is often considered important. This is because if the support and fixation of the superconducting field coil 7 is insufficient, there is a concern that the superconducting conductors forming the superconducting field coil 7 will move when electromagnetic force etc. act, generating frictional heat. be. The superconducting field coil 7 either achieves a superconducting state by satisfying the conditions of a certain current value, magnetic field strength, and temperature, or the generation of frictional heat causes a rise in the temperature of the coil, causing a transition from a superconducting state to a normal conducting state (quenching). ) may cause Therefore, when installing the coil, the shaft 6 is required to have high rigidity in order to firmly fix the superconducting field coil 7 in the slot 8 using a wedge or the like. However, in all of the above-mentioned conventional technologies, the coil attachment reduces the rigidity of the shaft 6, and the coil attachment with low rigidity causes the superconducting field coil 7 fixed to the shaft 6 to be affected by an increase in bending amplitude due to vibration, for example. This may cause quenching due to the effects of increased torsional displacement due to torsional vibration during short circuit.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to install a coil without reducing the rigidity of the shaft, to reduce vibrations caused by the anisotropy of the rigidity of the shaft, and to achieve stable superconducting. An object of the present invention is to provide a rotor for a superconducting rotating electric machine that can obtain the following state.

[Structure of the Invention] (Means for Solving the Problems) In order to solve the above problems, the present invention provides a room-temperature damper having rotating shaft portions at both ends and serving as a vacuum container, and a damper housed in the room-temperature damper. The coil is attached to the shaft, the superconducting conductor is housed in a slot formed on the surface of the shaft and forms a superconducting field coil, and the coil is attached to the shaft so that it is flexible in the axial direction relative to the normal temperature damper. In a rotor of a superconducting rotating electric machine having a flexible support, the flexible support has two elastic main shafts with different rigidities in a plane orthogonal to the rotation center axis of the shaft, and The elastic main shaft with high rigidity is arranged on the slot side of the shaft when the coil is mounted, and the elastic main shaft with low rigidity is arranged on the side of the shaft where the slot is not formed when the coil is mounted.

(Function) In the present invention, the shaft is flexibly supported with the flexible support as described above against the normal temperature damper, and the anisotropy of the rigidity of the shaft is canceled out by the flexible support, and the coil can be mounted without rotation. The anisotropy of the stiffness of the entire child is reduced. Therefore, there is no need to provide a separate groove on the shaft other than the slot for storing the superconducting field coil, and the coil installation does not reduce the rigidity of the shaft. Vibration can be reduced.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show a first embodiment of the present invention, and a second embodiment of the present invention is shown in FIG.
The figure is a partial sectional view of a superconducting rotor.

In the figure, 1 is a normal temperature damper, 2 is a rotating shaft, 5 is a flange, 6 is a coil mounting shaft, 7 is a superconducting field coil, 9
16 is liquid helium, and 16 is a radiation shield, which are the same as those shown in FIG.

In addition, 20 is a flexible support that flexibly supports the shaft 6 with respect to the room temperature damper 1 for mounting the coil.
As shown in FIG. 1, this flexible support 20 is formed from an inner ring 21, an outer ring 22, and a plurality of spokes 23 arranged radially between the inner ring 21 and the outer ring 22. The spokes 23 have different widths depending on their positions in the circumferential direction, and in the figure, the spokes 23 in the X-axis direction have a large width, and the spokes 23 in the Y-axis direction have a small width.

The flexible support 20 configured as described above is
Since the width of the spokes 23 in the X-axis direction is greater than the width of the spokes 23 in the Y-axis direction, the rigidity in the X-axis direction is greater than the rigidity in the Y-axis direction. Therefore, the two elastic main axes (X axis, Y axis,
As shown in Figure 3, the flexible support 20 with the coil is attached to the slot side of the axis 6, and the Y-axis, which is less rigid, is attached to the slot side of the axis 6. By placing it on the magnetic pole side of the shaft 6,
When the coil is attached, the rigidity anisotropy of the shaft 6 is canceled out by the flexible support 20, and the rigidity anisotropy of the rotor as a whole is reduced.

Therefore, when installing the coil, there is no need to separately provide a groove or the like other than the slot for housing the superconducting field coil 7 on the shaft 6.
The coil attachment can reduce vibrations caused by the anisotropy of the rigidity of the shaft 6 without reducing the rigidity of the shaft 6.

In the above embodiment, the width of the spokes 23 was changed to give the flexible support 20 rigidity anisotropy, but instead of changing the width of the spokes 23, the thickness of the spokes 23 may be changed, or the thickness of the spokes 23 may be changed. Both may be used together.

Furthermore, the same effect can be obtained by arranging the spokes 23 at irregular intervals as shown in FIG.

FIG. 5 and FIG. 6 are diagrams showing a third embodiment of the present invention,
In this embodiment, the flexible support 20 includes two flexible supports 24a.

24b. The flexible support 24a is made of a material with a high elastic modulus, and as shown in FIG. 7, the spokes 23 are present only in the X-axis direction. Further, the flexible support 24b is made of a material with a low elastic modulus, and as shown in FIG. 8, the spokes 23 are present in the Y-axis direction.

Therefore, these flexible supports 24a, 2
By overlapping and integrating 4b, the rigidity in the X-axis direction becomes greater than the rigidity in the Y-axis direction, similar to the flexible support shown in Figure 1, so installing the coil reduces the rigidity of the shaft 6. By attaching the coil to the shaft 6, vibrations caused by the anisotropy of the rigidity of the shaft 6 can be reduced.

[Effects of the Invention] As explained above, the present invention provides a room-temperature damper that has rotating shaft portions at both ends and also serves as a vacuum container, a coil housed in the room-temperature damper that is mounted on the shaft, and a coil that is mounted on the shaft. A superconducting rotating electric machine having a superconducting conductor that is housed in a slot formed on the surface of the machine and forming a superconducting field coil, and a flexible support that flexibly supports the shaft of the coil in the axial direction with respect to the normal temperature damper. In the rotor, the flexible support has two elastic main shafts with different rigidities on a plane perpendicular to the rotational center axis of the shaft, and the elastic main shaft with greater rigidity is the main shaft on which the coil is mounted. The coil is mounted on the side of the shaft where the slot is not formed, and the elastic main shaft with low rigidity is located on the side of the shaft where the slot is not formed.

Therefore, according to the present invention, since the anisotropy of the stiffness of the shaft is canceled out by the flexible support, the coil mounting does not reduce the stiffness of the shaft. can be reduced,
A rotor for a superconducting rotating electric machine that can obtain a stable superconducting state can be provided.

[Brief explanation of drawings]

1 to 3 are diagrams for explaining the first embodiment of the present invention, in which FIG. 1 is a front view of the flexible support, and FIG.
The figure is a partial sectional view of the superconducting rotor, the jIB figure is a diagram showing the positional relationship between the flexible support and the coil mounting shaft, Figure 4 is a front view of the flexible support showing the second embodiment of the present invention, and Figure 5 8 to 8 are diagrams for explaining the third embodiment of the present invention, in which FIG. 5 is a side view of the flexible support, FIG. 6 is a front view thereof, FIG. 7 is a front view of the flexible support, and FIG. The figure is a front view of the flexible pull support, Figures 9 to 12 are diagrams for explaining the conventional technology, Figure 9 is a schematic sectional view of a superconducting rotor, and Figure 10 shows the cross-sectional shape of the shaft for installing the coil. Figures 11 and 12 showing
The figure shows a conventional technique for reducing rotor vibration. 1... Normal temperature damper, 2, 3... Rotating shaft, 6... Coil mounting shaft, 7... Superconducting field coil, 8... Slot, 9... Liquid helium, 16...・Radiation shield, 20... Flexible support, 21... Inner ring, 22... Outer ring, 23... Spoke. Applicant's Representative Patent Attorney Takehiko Suzue Figure 5 Figure 6 Ward 7 Ward Ishi 8 Ward 3 Ward 4 1119 Figure 10

Claims (1)

[Claims] A room-temperature damper that has rotating shafts at both ends and doubles as a vacuum container;
A coil mounting shaft housed in this room temperature damper, a superconducting conductor that is housed in a slot formed on the surface of this coil mounting shaft and forming a superconducting field coil, and a coil mounting shaft that is connected to the room temperature damper. In a rotor of a superconducting rotating electrical machine having a flexible support that supports the coil in a flexible manner, the flexible support has two elastic main axes having different rigidities in a plane perpendicular to the central axis of the coil mounting shaft, and one of these elastic main axes is A rotor for a superconducting rotating electrical machine, characterized in that an elastic main shaft with high rigidity is arranged on the slot side of the coil mounting shaft, and an elastic main shaft with low rigidity is arranged on the side of the coil mounting shaft where the slot is not formed.