JPH04308452A - Rotor superconducting electric rotary machine - Google Patents

Abstract

PURPOSE:To provide a rotor for superconducting electric rotary machine having supporting structure of current lead pipe containing a current lead for feeding current to a superconducting field coil wherein insulator covering the current lead is protected against deterioration and liquid helium sump is sealed hermetically. CONSTITUTION:A superconducting field coil 5 is wound around a coil fixing shaft 4. Helium end plates 7 are disposed at the opposite ends of the coil fixing shaft 4 to form a liquid helium sump 8 between. A current lead 16 is connected at one end with the superconducting field coil 5. The current lead 16 is coated with an insulator 16b and the first welded part 23a of a thick ring coupling 23 is previously contained in a current lead pipe 16a subjected to seal welding. The current lead pipe 16a penetrates through the helium end plate 7 and secured through the thick ring coupling 23 to the other helium end plate 7 by subjecting the second welding part 3b of the thick ring coupling 23 and the helium end plate 7 to seal welding. The liquid helium sump 8 is sealed hermetically by the seal welded parts 24, 25.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a rotor for a superconducting rotating electric machine, and more particularly to a support structure for internal piping that houses current leads for supplying current to superconducting field coils in the rotor.

0002

[Prior Art] FIG. 2 shows, for example, Japanese Patent Application Laid-Open No. 57-166888
1 is a sectional view showing the structure of a rotor of a conventional superconducting rotating electric machine disclosed in the publication. In the figure, 1 is a hollow torque tube whose both ends are fixed to the flange 2a of the drive end shaft 2 and the flange 3a of the non-drive end shaft 3, and 4 is a hollow torque tube formed in the center of the torque tube 1. A hollow coil mounting shaft 5 is a superconducting field coil wound and fixed around the coil mounting shaft 4 . A helium outer cylinder 6 is disposed on the outer periphery of the coil mounting shaft 4, and helium end plates 7 as end plates are disposed on each of both side surfaces of the coil mounting shaft 4, and serve as a refrigerant reservoir. A liquid helium reservoir 8 is formed. Reference numeral 9 denotes a room-temperature damper whose both ends are fixed to the flange portion 2a of the drive-side end shaft 2 and the flange portion 3a of the non-drive-side end shaft 3, and is disposed to surround the torque tube 1 and the coil attachment shaft 4. , 10 is a low-temperature damper disposed between the coil mounting shaft 4 and the normal-temperature damper 9, 11 is a bearing that pivotally supports the drive side end shaft 2 and the non-drive side end shaft 3, and 12 is the torque tube 1. The formed or arranged heat exchanger, 13 is a side radiation shield provided inside the torque tube 1 on the outside of both side surfaces of the coil mounting shaft 4, and 14 is a vacuum section.

Reference numeral 15 denotes a slip ring for supplying field current provided on the opposite end shaft 3, and 16 penetrates the helium end plate 7 to electrically connect the superconducting field coil 5 and the slip ring 15. 16a is the current lead 16
This is a current lead tube that houses the current. 17 is a helium supply/discharge device attached to the shaft end of the non-drive side end shaft 3; 18 is a liquid helium supply pipe that communicates the liquid helium reservoir 8 with the helium supply/discharge device 17; and 19 is a liquid helium supply/discharge device. A helium pipe 20 communicates the liquid reservoir 8 and the heat exchanger 12, and 20 indicates a helium supply/discharge device 17 between the heat exchanger 12 and the heat exchanger 12.
A gas helium discharge pipe 21 communicates between the current lead pipe 16a and the helium supply/discharge device 17.

Next, the operation of the rotor of a conventional superconducting rotating electric machine will be explained. First, liquid helium, which is a refrigerant, is supplied from the helium supply/discharge device 17 to the liquid helium reservoir 8 via the helium supply pipe 18 . The superconducting field coil 5 is cooled to an extremely low temperature by the liquid helium in the liquid helium reservoir 8, and its electrical resistance becomes zero. The liquid helium in the liquid helium reservoir 8 evaporates due to the heat that enters through heat conduction from the torque tube 1 and the heat that enters through radiation from the low-temperature damper 10, and the helium that becomes a gas flows through the helium pipe 19. Once guided to the heat exchanger 12 through the gas helium exhaust pipe 20, after absorbing most of the heat that enters the torque tube 1 from the drive end shaft 2 and the non-drive end shaft 3, the helium It is discharged from the supply/discharge device 17 to the outside of the machine. In addition, the current lead 16 is in contact with a normal temperature part at the connection point with the slip ring 15, and the current lead 16 itself is made of copper and generates Joule heat when energized. Heat enters the section 8. The gaseous helium evaporated by the heat entering the current lead 16 flows through the current lead tube 16a, and
6 is discharged from the helium supply/discharge device 17 to the outside of the machine through the gas helium discharge pipe 21 while being cooled. Next, a field current is supplied from the slip ring 15 to the superconducting field coil 5 via the current lead 16 to excite the superconducting field coil 5. Since the superconducting field coil 5 has zero electrical resistance, it generates a strong magnetic field without excitation loss, and generates alternating current power in a stator (not shown).

In this manner, in order to cool and maintain the superconducting field coil 5 at an extremely low temperature, liquid helium is supplied to the liquid helium reservoir 8 while the inside of the rotor is kept in a high vacuum by the vacuum section 14. The torque tube 1 that transmits the rotational torque to the ultra-low temperature superconducting field coil 5 and the coil mounting shaft 4 is made of a thin-walled cylinder, and a heat exchanger 12 is provided. By flowing low-temperature gaseous helium through the heat exchanger 12, gas helium discharge pipe 20, and helium supply/discharge device 17, the heat that enters the cryogenic section through the torque tube 1 is reduced as much as possible. Additionally, side radiation shields 13 reduce heat entering due to radiation from the sides. Also,
The room temperature damper 9 and the low temperature damper 10 have the function of shielding harmonic magnetic fields from the stator, protecting the superconducting field coil 5, and damping rotor vibrations caused by disturbances in the power system. has a function as a vacuum outer cylinder, and the low temperature damper 10 also has a function as a radiation shield for the helium storage part 8.

Here, regarding the support structure of the current lead 16 in the rotor of the conventional superconducting rotating electrical machine shown in FIG.
This will be explained based on FIGS. 3 and 4. The current lead 16 is covered with an insulator 16b to prevent short circuit with the current lead tube 16a, and is housed in the current lead tube 16a, which is a pipe made of a metal without low-temperature brittleness such as austenitic stainless steel. has been done. This current lead tube 1
6a is directly seal welded to the helium end plate 7 at a seal welding portion 22 of a penetrating portion penetrating the helium end plate 7, and maintains the airtightness of the liquid helium reservoir portion 8.

[0007]

[Problems to be Solved by the Invention] Since the rotor of the conventional superconducting rotating electric machine is constructed as described above, when seal welding the current lead tube 16a and the helium end plate 7,
There was a problem in that the insulator 16b covering the current lead 16 deteriorated due to the heat of seal welding. This invention was made in order to solve the above-mentioned problems, and it maintains the airtightness of the refrigerant reservoir, and also securely connects the pipe to the end without deteriorating the insulation covering the current lead. The objective is to obtain a rotor for a superconducting rotating electric machine that can be seal-welded to a plate.

[0008]

[Means for Solving the Problems] A rotor for a superconducting rotating electric machine according to the present invention includes a first welding portion in which a current lead covered with an insulating material is seal-welded to the outer peripheral surface of the pipe before the current lead is housed in the pipe. The pipe is fixed to the end plate via a thick ring-shaped joint having a rear end plate housing a current lead and a second welded portion for seal welding.

[0009]

[Operation] In this invention, the second
The thickness of the welded part reduces the effect of heat associated with seal welding of the end plate and thick-walled ring-shaped joint on the insulator covering the current lead.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings. FIG. 1 is an enlarged sectional view of a main part showing an embodiment of a rotor of a superconducting rotating electric machine according to the present invention, and in the figure, the same or equivalent parts as the rotor of the conventional superconducting rotating electric machine shown in FIGS. 3 and 4 are shown. are given the same reference numerals and their explanations will be omitted. In the figure, 23 is a thick-walled ring-shaped joint, and this thick-walled ring-shaped joint 23 has a thin first welded part 23a at both ends and a thick second welded part 23b in the center.
is formed. Next, attachment of the current lead 16 will be explained. First, the thick-walled ring-shaped joint 23 is inserted into the current lead tube 16a, and the first welded portion 23a of the thick-walled ring-shaped joint 23 is seal-welded to the outer peripheral surface of the current lead tube 16a. The current lead pipe 16a and the thick-walled ring-shaped joint 23 are integrated at a seal weld 24 in a state where airtightness is maintained. Next, the current lead 16 covered with the insulator 16b is housed in the current lead tube 16a. Further, the current lead tube 16a is passed through the helium end plate 7, and one end of the current lead 16 is connected to the superconducting field coil 5. Thereafter, by seal-welding the second welded portion 23b of the thick-walled ring-shaped joint 23 integrated with the current lead pipe 16a and the helium end plate 7, the thick-walled ring-shaped joint 23 and the helium end plate 7 are separated. The seal weld 25 maintains airtightness, and the liquid helium reservoir 8 maintains airtightness.

As described above, in the above embodiment, before the current lead 16 is housed in the current lead tube 16a, the first welded portion 23a of the thick-walled ring-shaped joint 23 is attached to the current lead tube 16a.
It is seal welded to the outer circumferential surface of the thick ring joint 2.
When seal-welding the second welded portion 23b of 3 to the helium end plate 7, the second welded portion 23b of the thick-walled ring-shaped joint 23
Since the insulator 16b is thick, deterioration of the insulator 16b due to heat caused by seal welding can be prevented.

[0012] In the above embodiment, liquid helium was used as the refrigerant, but the present invention is not limited thereto.

[0013]

As described above, according to the present invention, the first welding part is seal-welded to the outer peripheral surface of the pipe before housing the current lead, and the second welding part is seal-welded to the rear end plate housing the current lead. Since the pipe is fixed to the end plate through a thick ring joint with a welded part, the heat generated by the seal welding between the thick ring joint and the end plate does not affect the insulation, and the refrigerant The present invention has the effect of providing a rotor for a superconducting rotating electrical machine that maintains the airtightness of the liquid reservoir, and also allows the pipe to be reliably seal-welded to the end plate without deterioration of the insulator covering the current lead.

[Brief explanation of drawings]

FIG. 1 is an enlarged sectional view of a main part showing an embodiment of a rotor of a superconducting rotating electric machine according to the present invention.

FIG. 2 is a sectional view showing an example of the position of a rotor of a conventional superconducting rotating electric machine.

FIG. 3 is an enlarged sectional view of a main part of a rotor of the conventional superconducting rotating electric machine shown in FIG. 2;

4 is a cross-sectional view of a current lead tube in the conventional superconducting rotating electric machine shown in FIG. 2. FIG.

[Explanation of symbols]

4 Coil mounting shaft 5 Superconducting field coil 7 Helium end plate 8 Liquid helium reservoir 16 Current lead 16a current lead tube 16b insulator 23 Thick ring joint 23a first welding part 23b second welding part

Claims (1)

[Claims] 1. A hollow coil mounting shaft around which a superconducting field coil is wound, a refrigerant reservoir provided in the coil mounting shaft, and a refrigerant reservoir provided at both ends of the coil mounting portion. an end plate that seals the liquid reservoir, a pipe that is disposed through the end plate, and a current that is housed within the pipe and covered with an insulating material and that is electrically connected to the superconducting field coil. A rotor of a superconducting rotating electric machine that is driven by supplying a field current through the current lead to excite the superconducting field coil, the current lead being covered with the insulating material. a thick-walled ring having a first welded portion that is seal-welded to the outer peripheral surface of the pipe before being accommodated in the pipe; and a second welded portion that is seal-welded to the end plate after the current lead is accommodated in the pipe; A rotor for a superconducting rotating electric machine, characterized in that the pipe is fixed to the end plate via a shaped joint.