Superconducting magnetic flux pump and excitation experimental system with volt-class DC voltage output

Abstract

The objective is to provide a superconducting magnetic flux pump and excitation experimental system having a volt-class DC voltage output. [Solution] The present invention relates to a superconducting flux pump and an excitation experimental system having a volt-class DC voltage output, belonging to the technical field of superconducting flux pumps. The superconducting flux pump uses a three-phase AC core and a DC bias core to form a magnetic coupling gap. When a three-phase AC current is supplied to the three-phase AC winding, magnetic flux is guided through the core, generating a traveling wave magnetic field in the magnetic coupling gap. The magnetic field generated by the DC bias winding is also guided through the core, generating a DC bias magnetic field in the magnetic coupling gap. The traveling wave magnetic field and the DC bias magnetic field are superimposed to generate a biased traveling wave magnetic field in the magnetic coupling gap, which acts on the superconducting stator in the magnetic coupling gap, thereby generating a DC voltage output. The present invention makes it possible to achieve a volt-class DC voltage output with a superconducting flux pump, significantly reducing the power supply cost of high-temperature superconducting magnets, contributing to a reduction in the burden on the cooling system, and enabling rapid charging of the superconducting coil and operation in persistent current mode.

Description

Technical Field

[0001] The present invention relates to the technical field of superconducting flux pumps, and particularly to a superconducting flux pump having a DC voltage output of the order of volts and an excitation experiment system.

Background Art

[0002] A superconducting magnet is a very important component in the field of superconducting power applications. Compared with conventional permanent magnets and general electromagnets, it has the characteristics of being lightweight, small-sized, capable of generating a stronger magnetic field, and having extremely low losses. Due to such excellent performance, superconducting magnets are applied in various fields such as medical, energy, and transportation. A superconducting magnet is a core component of various superconducting devices and provides a high-intensity and high-stability magnetic field.

[0003] A superconducting magnet needs to operate in a persistent current mode. A flux pump functions as a non-contact power source, injects a DC current into a closed loop composed of a superconducting stator and a superconducting magnet, and compensates for current decay caused by flux creep and welding resistance. Although Patent Document 1 details the configuration and operating principle of a linear flux pump, the conventional contact-type DC power source has a high cost, and due to the short effective coupling length of the linear flux pump, the output voltage is small, making it difficult to achieve rapid excitation and current conversion for a superconducting magnet, and it is limited to the use of maintaining the current of a superconducting magnet.

[0004] In short, it is an urgent issue to increase the effective coupling length of the flux pump on the superconducting stator and raise the output voltage to the order of volts. If this issue is reasonably resolved, it will be possible to effectively promote the industrial application of high-temperature superconducting magnets and superconducting flux pumps.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

[0006] To solve the above technical problems, the present invention provides a superconducting magnetic flux pump and an excitation experimental system having a volt-class DC voltage output. [Means for solving the problem]

[0007] In a first embodiment, the present invention provides a superconducting flux pump having a volt-class DC voltage output. The superconducting flux pump comprises a three-phase AC core, a DC bias core, a three-phase AC winding, a DC bias winding, and a cylindrical housing fitted to the outside of the DC bias core, wherein one end of the DC bias core is connected to one end of the cylindrical housing. Teeth slots are provided on the outside of the three-phase AC core, the three-phase AC windings are wound within the teeth slots of the three-phase AC core, the DC bias windings are wound on the outside of the DC bias core, one end of the three-phase AC core is positioned close to one end of the DC bias core, and a magnetic coupling gap is formed between the three-phase AC core and the cylindrical housing. When a three-phase AC current is supplied to the three-phase AC winding, magnetic flux is guided through the iron core, generating an alternating traveling wave magnetic field in the magnetic coupling gap between the tooth slot and the cylindrical housing. The magnetic field generated by the DC bias winding is also guided through the iron core, generating a DC bias magnetic field in the magnetic coupling gap between the tooth slot and the cylindrical housing. The traveling wave magnetic field and the DC bias magnetic field are superimposed to generate a biased traveling wave magnetic field in the magnetic coupling gap. The alternating traveling wave magnetic field is then biased by the DC bias magnetic field and acts on the superconducting stator in the magnetic coupling gap, generating a DC voltage output.

[0008] In a second aspect, the present invention provides an excitation experimental system based on a superconducting magnetic flux pump having a volt-class DC voltage output. The excitation experimental system is The system comprises a superconducting magnetic flux pump having a volt-class DC voltage output and a superconducting closed-loop magnet, the superconducting closed-loop magnet comprising a superconducting stator and a superconducting magnet, one end of the superconducting stator being positioned in the magnetic coupling gap of the superconducting magnetic flux pump and the other end being connected to the superconducting magnet. After the traveling wave magnetic field and the DC bias magnetic field are superimposed, a traveling wave magnetic field biased to the magnetic coupling gap is generated, which acts on the superconducting stator located in the magnetic coupling gap, thereby generating a DC voltage output.

[0009] Based on the technical means described above, the present invention can be further improved as follows.

[0010] Furthermore, the DC bias core is fixed on the disk, and one end of the cylindrical housing is fixed around the disk. The magnetic field generated by the DC bias core passes sequentially through the disk, cylindrical housing, tooth slot and three-phase AC core, and returns to the DC bias core, generating a DC bias magnetic field between the tooth slot and the cylindrical housing.

[0011] Furthermore, a DC bias winding is provided at one end of the three-phase AC winding, one end of the DC bias core is fixed on a disc, and one end of the cylindrical housing is fixed around the disc. Furthermore, DC bias windings are provided at both ends of the three-phase AC winding, one end of the DC bias core is fixed on one disk, the other end of the DC bias core is fixed on the other disk, one end of the cylindrical housing is fixed around one disk, and the other end of the cylindrical housing is fixed around the other disk.

[0012] Furthermore, the traveling magnetic field acts on the superconducting stator in the magnetic coupling gap, generating a DC voltage.

[0013] Furthermore, the superconducting stator is installed in the magnetic coupling gap between the tooth slot and the cylindrical housing using a helical winding system.

[0014] Furthermore, the superconducting magnet is constructed by stacking at least one superconducting double pancake coil concentrically in series or non-series, with support members fixing the spaces between the multiple concentrically stacked superconducting coils.

[0015] Furthermore, the orientation of the superconducting stator is perpendicular to the direction of propagation of the traveling magnetic field generated by the three-phase AC winding.

[0016] Furthermore, the superconducting stator is installed in the magnetic coupling gap of the superconducting flux pump using a helical winding method. [Effects of the Invention]

[0017] (1) The present invention enables the realization of a superconducting magnetic flux pump having a volt-class DC voltage output, thereby enabling rapid current conversion and maintenance of high current in superconducting magnets, and promoting further development of superconducting magnet excitation technology and industrial application of superconducting magnetic flux pumps. (2) The present invention utilizes a magnetic excitation principle based on magnetic flux dynamics, enabling the excitation of a magnet without requiring an external contact-type DC power supply by forming a closed loop between the superconducting stator and the superconducting coil. This magnetic excitation principle differs from conventional technology, eliminating the need for high-temperature superconducting magnets to rely on expensive DC power supplies, thereby significantly reducing the power supply costs of high-temperature superconducting magnets. (3) Because the present invention does not use current leads, the burden on the cooling system is greatly reduced, enabling rapid charging of high-temperature superconducting coils and operation in persistent current mode, and compensating for current attenuation due to magnetic flux creep and welding resistance in real time during operation, thereby greatly reducing energy consumption during operation. [Brief explanation of the drawing]

[0018] [Figure 1] This is a cross-sectional view of a superconducting magnetic flux pump having a volt-class DC voltage output, according to a first embodiment of the present invention. [Figure 2] This is a cross-sectional view of a superconducting flux pump according to an alternative embodiment of the first embodiment of the present invention. [Figure 3]It is a schematic perspective view of a superconducting flux pump having a bolt-level DC voltage output. [Figure 4] It is a schematic configuration diagram of a three-phase AC iron core. [Figure 5] It is a schematic diagram of the excitation operation of a superconducting flux pump having a bolt-level DC voltage output and a superconducting closed-loop magnet. [Figure 6] It is a schematic diagram showing the connection state between a superconducting magnet and a superconducting stator.

Embodiments for Carrying Out the Invention

[0019] To make the objects, technical means, and advantages of the embodiments of the present invention clearer, hereinafter, referring to the drawings in the embodiments of the present invention, the technical means in the embodiments of the present invention will be described in detail. However, the described embodiments are only some embodiments of the present invention, and it is needless to say that they are not all embodiments. The components of the embodiments of the present invention generally described and illustrated in this specification can be arranged and designed in various configurations.

[0020] (First Embodiment) As one embodiment, as shown in FIG. 1, in order to increase the effective coupling length of the flux pump on the superconducting stator, raise the output voltage of the flux pump to the bolt level, and realize large current output and rapid current conversion of the magnet, this embodiment provides a superconducting flux pump having a bolt-level DC voltage output. The superconducting flux pump includes a three-phase AC iron core 101, a DC bias iron core 102, a three-phase AC winding 103, a DC bias winding 104, and a cylindrical housing 105 fitted on the outside of the DC bias iron core 102. One end of the DC bias iron core 102 is connected to one end of the cylindrical housing 105. Teeth slots 106 are provided on the outside of the three-phase AC iron core 101. The three-phase AC winding 103 is wound in the teeth slots 106 of the three-phase AC iron core 101. The DC bias winding 104 is wound on the outside of the DC bias iron core 102. One end of the three-phase AC iron core 101 is arranged close to one end of the DC bias iron core 102. A magnetic coupling gap is formed between the three-phase AC iron core 101 and the cylindrical housing 105. When a three-phase AC current is supplied to the three-phase AC winding 103, magnetic flux is guided through the iron core, generating an alternating traveling wave magnetic field in the magnetic coupling gap between the tooth slot 106 and the cylindrical housing 105. The magnetic field generated by the DC bias winding 104 is also guided through the iron core, generating a DC bias magnetic field in the magnetic coupling gap between the tooth slot 106 and the cylindrical housing 105. The traveling wave magnetic field and the DC bias magnetic field are superimposed to generate a biased traveling wave magnetic field in the magnetic coupling gap. The alternating traveling wave magnetic field is then biased by the DC bias magnetic field and acts on the superconducting stator 201 in the magnetic coupling gap to generate a DC voltage output.

[0021] The superconducting flux pump is a contactless charging device for superconducting magnets. It generates a DC voltage by causing a traveling wave magnetic field generated in the magnetic coupling gap to couple with magnetic flux quanta on the superconducting stator, resulting in directional movement and generating a DC current within the superconducting magnet.

[0022] The superconducting stator 201 is provided in the magnetic coupling gap formed between the three-phase AC core 101 and the DC bias core 102, and by increasing the effective coupling length, the output voltage of the superconducting magnetic flux pump can be further increased.

[0023] In practical terms, by employing a multi-slot structure, the superconducting flux pump can increase the magnetic coupling gap area of ​​the flux pump, increase the effective coupling length of the superconducting stator, and improve the DC voltage output. The DC bias winding 104 comprises at least one, but when the superconducting flux pump employs a multi-slot structure, multiple DC bias windings 104 can be used to provide a sufficient DC bias magnetic field.

[0024] In practical applications, electromagnetic pure iron, grain-oriented silicon steel sheets, non-grain-oriented silicon steel sheets, and iron-based amorphous materials are commonly selected as core materials for superconducting magnetic flux pumps, possessing excellent permeability, high magnetic saturation intensity, and low iron loss.

[0025] In practical terms, superconducting flux pumps can be used while being cooled by immersion in liquid nitrogen or liquid helium, and can also be used outside of a cryogenic Dewar flask.

[0026] Alternatively, the three-phase AC core 101 and the DC bias core 102 are connected by screws.

[0027] As an alternative embodiment, as shown in Figure 1, the DC bias core 102 is fixed on the disc 107, and one end of the cylindrical housing 105 is fixed around the disc 107.

[0028] As an alternative embodiment, as shown in Figure 1, a DC bias winding 104 is provided at one end of the three-phase AC winding 103, one end of the DC bias core 102 is fixed on a disc 107, and one end of the cylindrical housing 105 is fixed around the disc 107.

[0029] As an alternative embodiment, as shown in Figure 2, DC bias windings 104 are provided at both ends of the three-phase AC winding 103, one end of the DC bias core 102 is fixed on one disc 107, the other end of the DC bias core 102 is fixed on the other disc 107, one end of the cylindrical housing 105 is fixed around one disc 107, and the other end of the cylindrical housing 105 is fixed around the other disc 107. In other words, DC bias windings 104 are provided at both ends of the three-phase AC winding 103, and discs 107 are fixed at both ends of the cylindrical housing 105.

[0030] Figure 3 is a schematic three-dimensional view of a superconducting flux pump having a volt-class DC voltage output. As shown in Figure 3, the flux pump as a whole is cylindrical, and the cylindrical housing 105 forms part of the DC bias core via a disc 107 and is arranged to enclose the three-phase AC core 101. The DC bias core is fixed on the disc 107, and one end of the cylindrical housing 105 is fixed around the disc 107, and the three-phase AC core and the DC bias core are assembled by screw coupling. A rectangular notch is drilled in the DC bias core to facilitate the installation and removal of the superconducting stator.

[0031] In an alternative embodiment, the DC bias core is fixed on a disk, and one end of the cylindrical housing is fixed around the disk. The magnetic field generated by the DC bias core passes sequentially through the disk, cylindrical housing, tooth slots, and three-phase AC core and returns to the DC bias core, generating a DC bias magnetic field between the tooth slots and the cylindrical housing.

[0032] The DC bias core of a superconducting flux pump with a volt-class DC voltage output can be manufactured as a single unit or assembled from segmented components. One end of the cylindrical housing is fixed to a disc, the DC bias core is fixed to the center of the disc, and an opening is formed on the side of the cylindrical housing.

[0033] As shown in Figure 4, the three-phase AC core 101 of a superconducting magnetic flux pump having a volt-class DC voltage output is usually manufactured as a single unit, with a cylindrical central section and a disc-shaped outer section. The tooth slots 106 between the discs facilitate winding work using round or flat copper wire. The number of slots in the three-phase AC core is not fixed, and the number of tooth slots 106 can be increased as needed when a higher voltage output is required.

[0034] Alternatively, the superconducting stator is provided in a helical winding configuration in the magnetic coupling gap between the tooth slot 106 and the cylindrical housing 105.

[0035] As an alternative embodiment, the present invention provides an extended superconducting magnetic flux pump having a volt-class DC voltage output. Unlike the embodiments described above, this extended volt-class magnetic flux pump comprises two DC bias cores and a DC bias winding, and aims to provide a stronger DC bias magnetic field.

[0036] As an alternative embodiment, unlike the embodiments described above, the number of tooth slots and three-phase AC windings of the three-phase AC core of the extended volt-class superconducting magnetic flux pump are significantly increased, and the number of tooth slots and three-phase AC windings of the three-phase AC core can be customized according to the output voltage requirements. The length and number of DC bias cores and DC bias windings are changed according to the length of the three-phase AC core, and the longer the three-phase AC core and the greater the number of tooth slots, the longer the DC bias cores and DC bias windings will be.

[0037] This invention enables the realization of volt-level DC voltage output using a superconducting flux pump, thereby facilitating rapid current conversion and maintenance of high currents in superconducting magnets, and promoting further development of superconducting magnet excitation technology and industrial applications of superconducting flux pumps.

[0038] This invention utilizes a magnetic excitation principle based on magnetic flux dynamics, enabling the excitation of a magnet without requiring an external DC power supply for extended periods by forming a closed loop between the superconducting stator and superconducting coil. This magnetic excitation principle differs from conventional technologies, eliminating the need for high-temperature superconducting magnets to rely on expensive DC power supplies, significantly reducing the power supply costs for such magnets.

[0039] Because this invention does not use current leads, the burden on the cooling system is greatly reduced, enabling rapid charging and operation in persistent current mode of high-temperature superconducting coils. Furthermore, it compensates for current attenuation due to magnetic flux creep and welding resistance in real time during operation, and greatly reduces energy consumption during operation.

[0040] (Second embodiment) Based on the same principle as the method shown in the first embodiment of the present invention, one embodiment of the present invention provides an excitation experiment system based on a superconducting magnetic flux pump having a volt-class DC voltage output. The excitation experiment system is The first embodiment comprises a superconducting flux pump having a volt-class DC voltage output and a superconducting closed-loop magnet, the superconducting closed-loop magnet comprising a superconducting stator 201 and a superconducting magnet 202, one end of the superconducting stator 201 being positioned in the magnetic coupling gap of the superconducting flux pump and the other end being connected to the superconducting magnet 202. After the traveling wave magnetic field and the DC bias magnetic field are superimposed, a traveling wave magnetic field biased to the magnetic coupling gap is generated, which acts on the superconducting stator 202 located in the magnetic coupling gap to generate a DC voltage output.

[0041] As shown in Figure 5, in an alternative embodiment, the superconducting stator 201 is installed perpendicular to the direction of travel of the traveling wave. The superconducting stator 201 is positioned between the three-phase AC core and the DC bias core of the superconducting flux pump 100, forming a magnetic coupling gap. The superconducting magnet 202 is connected to the superconducting stator 201. When using a helical winding system, the superconducting stator 201 must be kept as perpendicular as possible to the direction of travel of the wave. Figure 6 is a schematic diagram showing the connection between the superconducting magnet 202 and the superconducting stator 201.

[0042] As an alternative embodiment, an extended superconducting flux pump excitation experimental system having a volt-class DC voltage output comprises at least one extended volt-class flux pump and at least one superconducting magnet, wherein the extended superconducting flux pump generates a traveling wave magnetic field biased to the magnetic coupling gap between a three-phase AC core and a DC bias core, and the traveling wave magnetic field moves flux quanta on a superconducting stator in a directional manner, ultimately outputting a volt-class DC voltage to the superconducting magnet.

[0043] As an alternative embodiment, the superconducting stator can be made of high-temperature superconducting ReBCO tape, which is connected in series with the superconducting magnet to form a closed loop. The ReBCO tape comprises a Hastelloy alloy layer as a base material, a ReBCO layer, and a buffer layer, where ReBCO is a superconducting material and Re represents a rare earth element, and the operating temperature of the superconducting magnet is 90K or less.

[0044] Alternatively, the orientation of the superconducting stator 201 is perpendicular to the direction of propagation of the traveling magnetic field generated by the three-phase AC winding.

[0045] Alternatively, the superconducting stator 201 is provided in the magnetic coupling gap of the superconducting flux pump 100 using a helical winding method.

[0046] The superconducting magnet 202 is wound from a superconducting material and typically employs a double pancake coil winding. The superconducting magnet 202 is constructed by stacking at least two superconducting double pancake coils concentrically in series or non-series, with support members fixing the spaces between the concentrically stacked superconducting coils.

[0047] In practical applications, superconducting stators and superconducting magnets are cooled to a superconducting state using refrigerators, cooling helium gas, or liquid helium.

[0048] As an alternative embodiment, an extended volt-class superconducting flux pump is excited by a helically wound superconducting stator, and superconducting magnets are connected to the superconducting flux pump via the superconducting stator, with a cylindrical housing containing a DC bias core concealed in the figure. The superconducting stator, when combined with the extended superconducting flux pump using a helical winding method, can increase the DC voltage output of the superconducting flux pump. The helical winding method makes it possible to keep the direction of movement of the traveling wave magnetic field as perpendicular as possible to the orientation of the superconducting stator.

[0049] Alternatively, the superconducting magnet may be constructed by stacking at least one superconducting double pancake coil concentrically in series or non-series, with support members fixing the spaces between the concentrically stacked superconducting coils.

[0050] The embodiments described above are merely preferred examples of the present invention and do not limit it. Those skilled in the art can make various changes and modifications based on the technical idea of ​​the present invention. Any modifications, substitutions with equivalents, and improvements made within the spirit and principles of the present invention are covered by the present invention. [Explanation of symbols]

[0051] 100 Superconducting Magnetic Flux Pumps 101 Three-phase AC iron core 102 DC bias iron core 103 Three-phase AC winding 104 DC bias winding 105 Cylindrical housing 106 Teeth Slots 107 discs 201 Superconducting Stator 202 Superconducting Magnet

Claims

1. A superconducting magnetic flux pump having a volt-class DC voltage output, the superconducting magnetic flux pump comprises a three-phase AC core (101), a DC bias core (102), a three-phase AC winding (103), a DC bias winding (104), and a cylindrical housing (105) fitted to the outside of the DC bias core (102), with one end of the DC bias core (102) connected to one end of the cylindrical housing (105). A tooth slot (106) is provided on the outside of the three-phase AC core (101), the three-phase AC winding (103) is wound inside the tooth slot (106) of the three-phase AC core (101), the DC bias winding (104) is wound on the outside of the DC bias core (102), one end of the three-phase AC core (101) is positioned close to one end of the DC bias core (102), and a magnetic coupling gap is formed between the three-phase AC core (101) and the cylindrical housing (105). When a three-phase AC current is supplied to the three-phase AC winding (103), magnetic flux is guided through the iron core, generating an alternating traveling wave magnetic field in the magnetic coupling gap between the tooth slot (106) and the cylindrical housing (105). The magnetic field generated by the DC bias winding (104) is also guided through the iron core, generating a DC bias magnetic field in the magnetic coupling gap between the tooth slot (106) and the cylindrical housing (105). The traveling wave magnetic field and the DC bias magnetic field are superimposed to generate a biased traveling wave magnetic field in the magnetic coupling gap. The alternating traveling wave magnetic field is then biased by the DC bias magnetic field and acts on the superconducting stator (201) in the magnetic coupling gap to generate a DC voltage output. A superconducting magnetic flux pump having a volt-class DC voltage output, characterized by the following features.

2. A superconducting magnetic flux pump having a volt-class DC voltage output, characterized in that the DC bias core (102) is fixed on a disk (107), one end of the cylindrical housing (105) is fixed around the disk (107), the cylindrical housing (105) is fitted to the outside of the DC bias core (102), the magnetic field generated by the DC bias core (102) passes sequentially through the disk (107), the cylindrical housing (105), the tooth slot (106), and the three-phase AC core (101) and returns to the DC bias core (102), and a DC bias magnetic field is generated between the tooth slot (106) and the cylindrical housing (105).

3. A superconducting magnetic flux pump having a volt-class DC voltage output, characterized in that one end of the three-phase AC winding (103) is provided with the DC bias winding (104), one end of the DC bias core (102) is fixed on the disc (107), and one end of the cylindrical housing (105) is fixed around the disc (107).

4. A superconducting magnetic flux pump having a volt-class DC voltage output, characterized in that a DC bias winding (104) is provided at both ends of the three-phase AC winding (103), one end of the DC bias core (102) is fixed on one of the discs (107), the other end of the DC bias core (102) is fixed on the other disc (107), one end of the cylindrical housing (105) is fixed around one of the discs (107), and the other end of the cylindrical housing (105) is fixed around the other disc (107), as described in claim 1.

5. A superconducting magnetic flux pump having a volt-class DC voltage output, characterized in that a traveling wave magnetic field acts on the superconducting stator (201) in the magnetic coupling gap, thereby generating a DC voltage.

6. The superconducting magnetic flux pump having a volt-class DC voltage output, characterized in that the superconducting stator (201) is provided in a helical winding manner in the magnetic coupling gap between the tooth slot (106) and the cylindrical housing (105).

7. An excitation experiment system based on a superconducting magnetic flux pump having a volt-class DC voltage output as described in claim 1, A superconducting magnetic flux pump having a volt-class DC voltage output as described in claim 1, and a superconducting closed-loop magnet, wherein the superconducting closed-loop magnet comprises a superconducting stator (201) and a superconducting magnet (202), one end of the superconducting stator (201) is positioned in the magnetic coupling gap of the superconducting magnetic flux pump, and the other end is connected to the superconducting magnet (202), After the traveling wave magnetic field and the DC bias magnetic field are superimposed, a traveling wave magnetic field biased to the magnetic coupling gap is generated and acts on the superconducting stator (201) located in the magnetic coupling gap, thereby generating a DC voltage output. An excitation experiment system based on a superconducting magnetic flux pump having a volt-class DC voltage output, characterized by the following features.

8. The excitation experimental system based on a superconducting magnetic flux pump having a volt-class DC voltage output, characterized in that the superconducting magnet (202) is constructed by stacking at least one superconducting double pancake coil concentrically in series or non-series, and the spaces between the concentrically stacked superconducting coils are fixed by support members, as described in claim 7.

9. An excitation experimental system based on a superconducting magnetic flux pump having a volt-class DC voltage output, characterized in that the orientation of the superconducting stator (201) is perpendicular to the direction of propagation of the traveling wave magnetic field generated by the three-phase AC winding (103), as described in claim 7.

10. The excitation experimental system based on a superconducting flux pump having a volt-class DC voltage output, characterized in that the superconducting stator (201) is provided in the magnetic coupling gap of the superconducting flux pump in a helical winding manner.

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