CN201478345U

CN201478345U - Superconducting switch

Info

Publication number: CN201478345U
Application number: CN2009201486280U
Authority: CN
Inventors: 王超; 方志春
Original assignee: Siemens Shenzhen Magnetic Resonance Ltd
Current assignee: Siemens Shenzhen Magnetic Resonance Ltd
Priority date: 2009-03-31
Filing date: 2009-03-31
Publication date: 2010-05-19
Anticipated expiration: 2019-03-31

Abstract

The utility model discloses a superconducting switch comprising at least two parallel switch coils. The superconducting switch can ensure the working current of a magnet to equally flow through each switch coil as far as possible through the production inspection and control, thereby improving the stability of a magnetic switch and effectively preventing the quench of a magnetic closed loop.

Description

A kind of superconducting switch

Technical field

The utility model relates to the superconductor technology field, particularly a kind of superconducting switch.

Background technology

In the superconducting magnet of magnetic resonance imaging (MRI) equipment, need the superconducting switch of two parallel connections usually, can reduce like this because switch is former thereby cause the risk of quench.That is to say that in the time of can not working even one of them superconducting switch breaks down, another superconducting switch can be born the current loading that two superconducting switchs of former cause are born.Under normal conditions, two superconducting switchs are worked in magnet together, and each superconducting switch is only born the load current of half, like this can so that superconducting switch more stably work.Yet, because the resistance of tie point is usually different between each superconducting switch and the superconducting coil, so the electric current on each superconducting switch is also different.

Fig. 1 has provided the connection diagram of superconducting switch of the prior art and superconducting magnet.As shown in Figure 1, comprise two

superconducting switchs

10 and 20 in MRI equipment, these two superconducting switchs are connected with magnet 30.Wherein, superconducting switch 10 has two

superconduction tie points

11 and 12, and superconducting switch 20 has two superconduction tie points 13 and 14.Superconducting switch 10 is connected with magnet 30 with 16 by superconduction tie point 15 with 20.Superconduction tie point the 11,12,13, the 14th forms in the manufacture process of

switch

10,20, and superconduction tie point the 15, the 16th forms in the process of making magnet.Superconduction

tie point

11,12,13,14 connects two superconductivity wires separately, that is, and and switch wire and switch fly line.Superconduction

tie point

15,16 connects three superconductivity wires separately, that is, and and two switch fly lines and a magnet wire.Being connected resistance and may having greatest differences of switch fly line and magnet wire in the

superconduction tie point

15,16, the electric current that flows into each superconducting switch so can be different therefrom.In the worst case, a superconducting switch (for example superconducting switch 10) is born most operating current, and 20 of another superconducting switchs are born very little electric current.This just makes the superconducting switch 10 of bearing great current become unstable, easy quench, thus cause the superconducting magnet quench.

In the prior art, mainly improve the stability of superconducting switch by dual mode.First kind of mode realizes by the design of magnet.Because it is more stable to have the switch of less operating current, thus the superconducting magnet of less operating current can be designed, less with this electric current of realizing flowing through superconducting switch, thus the stability of superconducting switch improved.Yet this method needs more magnet wire to realize identical magnetic field, and the result has not only strengthened the complexity on the superconducting magnet structure, has also increased the cost of superconducting magnet.

Another kind of mode is by the design of superconducting switch and makes and realize.Use high performance superconductivity wire and better technology to make switch, can improve the critical current of superconducting switch, thereby make superconducting switch under higher electric current, still keep stable.But,, increased the manufacturing cost of superconducting switch owing to the change of material and technology.In addition, verify the reliability of a new superconducting switch, usually need a plurality of superconducting switchs to be measured are connected in the superconducting magnet operation with closed ring above time of half a year at least.

The utility model content

In view of this, the utility model proposes a kind of superconducting switch, in order to improve the stability of superconducting switch.

Therefore, the utility model provides a kind of superconducting switch, and this superconducting switch comprises the switch coil of at least two parallel connections.

In one embodiment, described switch coil is arranged side by side.

In another embodiment, described switch coil is arranged among the row.

In technique scheme, the superconduction tie point of described switch coils from parallel connection of coils is formed by Wood's metal or cerrobase alloy perfusion.

In technique scheme, an end of described switch coils from parallel connection of coils is connected with magnet wire by a fly line.

In technique scheme, the superconduction tie point of described fly line and magnet wire is formed by Wood's metal or cerrobase alloy perfusion.

As can be seen, superconducting switch of the present utility model can make magnet operating current each switch coil of as far as possible flowing through fifty-fifty by its production testing control, thereby has improved the stability of magnet switch, prevents magnet closed loop quench effectively from such scheme.Because superconducting switch of the present utility model is made up of the switch coil of two parallel connections at least, compare with the superconducting switch of prior art, superconducting switch of the present utility model has reduced by two superconduction tie points, can reduce the cost of superconducting switch, and has reduced the magnet current decay.Superconducting switch of the present utility model has smaller volume, only needs less downfield working space (to connect for the Wood's metal superconduction, need be placed on the magnetic field less than 0.8T usually; Connect for the cerrobase alloy superconduction, need be placed on less than the magnetic field about 1.2T usually) get final product, be easier to the design and assembly magnet like this.

In addition, because superconducting switch of the present utility model has just connected at least two switch coils during fabrication, so can in the process of producing superconducting switch, carry out matching control to the switch coil, be suitable for mass production, and switch coil of the prior art is separate, if the test matching then needs extra superconduction to connect and corresponding frock, be unsuitable for mass production.

Description of drawings

Fig. 1 is the connection diagram of superconducting switch in the prior art;

Fig. 2 is the connection diagram according to superconducting switch of the present utility model;

Fig. 3 is the superconducting switch according to a kind of execution mode of the present utility model;

Fig. 4 is the superconducting switch according to another kind of execution mode of the present utility model;

Fig. 5 is the position view of superconducting switch shown in Figure 4 in superconducting magnet.

Embodiment

For making the purpose of this utility model, technical scheme and advantage clearer, by the following examples the utility model is further described.

In order to make those skilled in the art's easy to understand the utility model, in the embodiment below, comprise that with superconducting switch two switch coils are that example describes.

Figure 2 shows that according to the superconducting switch of a kind of execution mode of the utility model and the connection diagram of superconducting magnet.As shown in Figure 2, superconducting switch 40 has two independently switch coils, and each switch coil can be shared electric current.These two switch coils are connected in parallel by superconduction tie point 41,42.Superconducting switch 40 is by being connected with superconducting magnet by two superconduction tie points 43,44.Different with the superconducting switch that has only a switch coil in the prior art, superconducting switch of the present utility model has two independently switch coils, these two switch coils not only can be shared electric current jointly, can also backup each other, when one of them switching line was irised out existing fault, another switch coil can be born all electric currents.According to superconducting switch of the present utility model, can reduce by two superconduction tie points, can reduce the cost of superconducting switch like this, can also reduce existing current attenuation.

In Fig. 2,

superconduction tie point

41,42 connects two switch coils and a switch fly line separately.Superconduction

tie point

43,44 connects a switch fly line and a magnet wire separately.Superconduction

tie point

41,42 forms in the process of making switch.Therefore, in making the process of switch, being connected resistance and can obtaining measuring between each switch coil and the switch fly line, thus control these connection resistance identical or close.So, the electrorheological that flows into each superconducting switch gets identical or close.These two switch wires are shared electric current fifty-fifty.This will improve the stability of superconducting switch, and reduce the quench of magnet.

Fig. 3 has provided the schematic diagram according to the superconducting switch of a kind of execution mode of the utility model.Fig. 4 has provided the schematic diagram according to the superconducting switch of the another kind of execution mode of the utility model.In Fig. 3, two

switch coils

50,60 are arranged side by side, and are connected in parallel between

superconduction tie point

51 and 61, and wherein the axis normal of

switch coil

50,60 is in the direction of Fig. 3 paper.In Fig. 4, two switch coils 70,80 are arranged among the row, are connected in parallel between superconduction tie point 71 and 81, and wherein the axis of switch coil 70,80 is the above-below direction in Fig. 4 paper.

Fig. 5 has provided the position view of superconducting switch 90 shown in Figure 4 in superconducting magnet 30.

According to the superconductivity of DISTRIBUTION OF MAGNETIC FIELD and Wood's metal (Woods Metal), superconducting switch need be placed on usually in the magnetic field less than 0.8T.Wood's metal is used for the superconduction tie point of superconducting switch.In the superconducting magnet of MRI equipment, especially in the high-intensity magnetic field magnet such as 3T, be difficult to find enough big downfield space that superconducting switch is installed less than 0.8T.Sometimes in order to obtain the 0.8T working space, need design again, for example increase shim coil magnet.Will increase the manufacturing complexity and the cost of magnet like this.Superconducting switch of the present utility model can address this problem well, because compare with two conventional switch of the prior art, superconducting switch volume of the present utility model is little, and has superconduction tie point still less.

In addition, the superconducting magnet coil of nearly all MRI equipment all is cylindrical structural on the whole, so magnetic field equipotential lines picture as shown in Figure 5 ringwise.Superconducting switch 90 as shown in Figure 4 can be installed in circumferencial direction as shown in Figure 5, thereby only needs less 0.8T working space to get final product.That is, superconducting switch shown in Figure 4 is compared with superconducting switch shown in Figure 3, needs less 0.8T working space.

The above only is preferred embodiment of the present utility model; not in order to restriction the utility model; all within spirit of the present utility model and principle, any modification of being done, be equal to replacement, improvement etc., all should be included within the protection range of the present utility model.

Claims

1. a superconducting switch is characterized in that, this superconducting switch comprises the switch coil of at least two parallel connections.

2. superconducting switch according to claim 1 is characterized in that, described switch coil is arranged side by side.

3. superconducting switch according to claim 1 is characterized in that, described switch coil is arranged among the row.

4. superconducting switch according to claim 1 is characterized in that, an end of described switch coils from parallel connection of coils is connected with magnet wire by a fly line.

5. superconducting switch according to claim 4 is characterized in that, the superconduction tie point of described fly line and magnet wire is formed by Wood's metal or cerrobase alloy perfusion.

6. superconducting switch according to claim 1 is characterized in that, the superconduction tie point of described switch coils from parallel connection of coils is formed by Wood's metal or cerrobase alloy perfusion.