JPH0622965Y2 - Superconducting coil device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial field of application) The present invention relates to a superconducting coil device with a thermal permanent current switch that enables permanent electric operation used in a magnetic levitation train or the like.

(Prior Art) The conventional superconducting coil device with a thermal permanent current switch is the third
As shown in the figure, a superconducting coil main body 2 and a thermal permanent current switch 3 are housed in an inner tank container 1 filled with liquid helium. The switch is often installed above or below the R portion of the race track, and the lead-out portion 3a of the switch and the connecting portion 4 between the switch lead-out portion 3b and the lead wire 2a of the coil reduce the instability of the lead-out wire portion. Therefore, the length of the lead wire is short and the lead wire is arranged near the coil body 2. In addition, the superconducting coil device includes a vacuum tank, a pipe,
A radiation shield plate, various ports, and sensors are also installed, but they have been omitted for the sake of simplicity.

(Problems to be solved by the invention) The thermal permanent current switch 3 is covered with a heat insulating pan 3c as shown in Fig. 4 so that the superconducting wire can be heated to a resistance state, and the movement of the lead-out portion 3b When heat from the lead-out portion 3a is generated, if the lead-out portion 3a is located close to the coil body 2, the ambient magnetic field is high, so the thermal allowable value of the superconducting wire, which is the lead-out wire, decreases, There was a risk of quenching the entire switch due to the transition from the superconducting state to the normal conducting state with respect to the heat generation of. In particular, this tendency is remarkable when the coil becomes large and the peripheral magnetic field becomes large. Similarly, the connecting portion 4 between the switch lead wire 3b and the coil lead wire 2a
When placed in a place near the coil body 2 where the surrounding magnetic field is high,
There is a high possibility that the superconducting wire at the connecting portion will change to the normal conducting state due to the heat generated due to the connection and AC loss during the excitation / demagnetization, and there is a risk of quenching the coil and the switch.

The present invention is a superconducting coil device that prevents quenching at a lead portion of a switch and quenching at a joint portion between a lead wire of a switch and a lead wire of a coil.

[Constitution of device]

(Problems to be Solved by the Invention) The present invention has a structure in which the lead-out portion of the thermal permanent current switch and the connecting portion between the lead-out wire of the switch and the lead-out wire of the coil are arranged at a low ambient magnetic field position away from the coil body. Take

(Function) Since the position of the switch lead and connection is far from the coil body, and the ambient magnetic field is low, the thermal allowable value of the superconducting wire is large, and the heat generated due to overheating of the lead and connection loss As a result, the normal conduction transition of the lead wire is less likely to occur, and the occurrence of quench can be reduced.

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

FIG. 1 shows a specific embodiment of the thermal permanent current switch lead portion 3a, switch lead portion 3b and coil lead wire 2a.
The connecting portion 4 for connection with is arranged at a position separated from the coil body 2. Although the length of the coil lead wire 2a becomes longer,
Stabilization of the lead wire is aimed at by providing a stabilizing material such as copper.

With the structure as described above, the ambient magnetic field around the lead-out portion 3a and the connecting portion 4 of the switch becomes small, the thermal allowance of the superconducting wire that is the lead-out wire becomes large, and the normal-conducting transition hardly occurs. As an example, in the case of a coil with a magnetomotive force of 700 KA class, the magnetic field is 2.51T, 130 mm at the position 30 mm outside the coil winding.
In the position of, it drops to 0.51T and 1/5. In this way, the magnetic field strength can be reduced to a fraction by separating from the coil winding portion.

Due to the above-mentioned action, heat generation at the mouth 3a,
Even if heat is generated due to a connection loss at the connection portion 4, the normal transition of the lead wire does not occur, so that the occurrence of quench in the switch body and the coil body can be reduced.

As shown in FIG. 2, when the thermal permanent current switch 3 is composed of a plurality of two or more, they are connected in parallel and the connecting portion 5 with the coil lead wire 2a is connected to the coil main body 2 in the same manner as above.
By arranging at a position farther away and having a lower ambient magnetic field, the same effect as described above can be expected.

[Effect of device]

As described above, in a superconducting coil device with a thermal permanent current switch capable of operating a permanent current, the output part of the switch and the connection part between the output wire of the switch and the output wire of the coil are surrounded by an ambient magnetic field. By placing it at a low position, the superconducting wire, which is the lead wire, will not easily change to normal conduction due to the heat generated by the heat generated at the lead wire and the heat generated by the connection loss at the connection part, and quenching of the switch body and coil body will occur. Can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram of a superconducting coil device according to an embodiment of the present invention, FIG. 2 is a block diagram of a superconducting coil device according to another embodiment of the present invention, and FIG. 3 is a block diagram of a conventional superconducting coil device. FIG. 4 is a sectional view of the thermal permanent current switch. 1 ... Inner tank, 2 ... Superconducting coil, 2a ... Coil lead wire, 3 ... Thermal permanent current switch, 3a ... Switch lead wire, 3b ... Switch lead wire, 3c ... Switch heat insulation pot, 4 ... Connection part, 5 ... Connection.

Claims (1)

[Scope of utility model registration request] 1. In a superconducting coil device having a thermal permanent current switch that enables permanent current operation, a lead-out portion of the permanent current switch and a connecting portion with a coil-side superconducting wire are connected to the main body of the permanent current switch by a magnetic field. A superconducting coil device, which is installed at a position farther from the coil body.