Superconducting flux pump, system and control method based on alternating magnetic field coupling

Abstract

The present disclosure provides a superconducting flux pump, system and control method based on alternating magnetic field coupling, the superconducting flux pump comprising: a transformer, comprising a first iron core and a primary winding and a secondary winding wound around the first iron core, the primary winding being connected to a first AC power source, the secondary winding and a superconducting flux bridge forming a first closed loop for providing an induced current corresponding to the current on the primary winding to the superconducting flux bridge; an electromagnet, comprising a second iron core and a winding wound around the second iron core, the second winding being connected to a second AC power source, for applying an alternating magnetic field to the superconducting flux bridge so that a DC voltage is induced at both ends of the superconducting flux bridge; and a superconducting coil, forming a second closed loop with the superconducting flux bridge, so as to excite the superconducting coil with a DC voltage.

Description

Technical Field

[0001] The present disclosure relates to the technical field of superconducting magnets, and in particular to a superconducting flux pump based on alternating magnetic field coupling. Background Art

[0002] High-temperature superconducting tapes have high critical current density and critical magnetic field strength, and high-temperature superconducting magnets made of them have great application potential in the field of strong magnetic fields. However, due to the inherent characteristics of high-temperature superconducting tapes, high-temperature superconducting magnets cannot operate in a closed loop in the "continuous current mode" like low-temperature superconducting magnets. This is mainly caused by the following two reasons: First, in high-temperature superconducting tapes, the extremely thin superconducting layer is encapsulated in a protective layer, and the resistance of the welding joint cannot be avoided, so Joule heat loss will be generated, causing the current in the closed-loop high-temperature superconducting magnet to continue to decay; second, high-temperature superconducting materials will produce magnetic flux creep due to thermal activation, which will also cause the current in them to decay.

[0003] In the process of implementing the embodiments of the present disclosure, the inventors discovered that the use of a DC power supply to directly excite a high-temperature superconducting magnet in related examples has the problems of high excitation cost and low excitation efficiency. Summary of the invention

[0004] In view of this, the main purpose of the present invention is to provide a superconducting flux pump, system and control method based on alternating magnetic field coupling, in order to partially solve at least one of the above technical problems.

[0005] In order to achieve the above-mentioned object, the present invention provides a superconducting flux pump based on alternating magnetic field coupling, a system and a control method thereof.

[0006] According to a first aspect of the present disclosure, a superconducting flux pump based on alternating magnetic field coupling is provided, comprising:

[0007] The transformer comprises a first core and a primary winding and a secondary winding wound around the first core, wherein the primary winding is connected to a first AC power source, and the secondary winding and a superconducting flux bridge form a first closed loop for providing an induced current corresponding to a current on the primary winding to the superconducting flux bridge.

[0008] The electromagnet comprises a second core and a winding wound around the second core; the second winding is connected to a second AC power source and is used to apply an alternating magnetic field to the superconducting flux bridge so that a DC voltage is induced at both ends of the superconducting flux bridge.

[0009] The superconducting coil and the superconducting flux bridge form a second closed loop to excite the superconducting coil using a DC voltage.

[0010] According to an embodiment of the present disclosure, the electromagnet comprises:

[0011] The forward electromagnet includes a second core and a winding wound around the second core, wherein the second winding is connected to a second AC power supply and is used to apply an alternating magnetic field to the first superconducting flux bridge so that a first DC voltage is induced at both ends of the first superconducting flux bridge, wherein a direction of the first DC voltage is the same as a forward current direction of the first AC power supply.

[0012] The negative electromagnet includes a third core and a winding wound around the third core, wherein the third winding is connected to a third AC power supply and is used to apply an alternating magnetic field to the second superconducting flux bridge so that a second DC voltage is induced at both ends of the second superconducting flux bridge, wherein the direction of the second DC voltage is opposite to the negative current direction of the first AC power supply.

[0013] According to an embodiment of the present disclosure, the number of electromagnets corresponds to the number of secondary windings and the number of flux bridges.

[0014] According to an embodiment of the present disclosure, the induction surface of the superconducting flux bridge is perpendicular to the magnetic induction direction of the alternating magnetic field.

[0015] According to an embodiment of the present disclosure, the ratio of the number of turns of the primary winding to the number of turns of the secondary winding includes: 20:1~200:1.

[0016] According to an embodiment of the present disclosure, the superconducting flux bridge, the secondary winding and the superconducting coil are all made of superconducting materials.

[0017] According to an embodiment of the present disclosure, the secondary winding, the superconducting flux bridge and the superconducting coil are disposed in a container at a predetermined temperature, and the predetermined temperature is less than the critical transition temperature of the superconducting material.

[0018] According to an embodiment of the present disclosure, the superconducting flux bridge, the secondary winding and the superconducting coil are all in a superconducting state.

[0019] Another aspect of the present disclosure provides a superconducting flux system based on alternating magnetic field coupling, comprising: the above-mentioned superconducting flux pump and a controller.

[0020] The controller is electrically connected to the first AC power source and the second AC power source, and is used to control the working state of the electromagnet according to the direction of the alternating current in the primary winding, and to adjust the working parameters of the first AC power source and the second AC power source.

[0021] Another aspect of the present disclosure provides a control method for a superconducting magnetic flux system based on alternating magnetic field coupling, comprising:

[0022] In response to detecting that the direction of the initial winding alternating current is a predetermined direction, the AC power supply corresponding to the predetermined direction is controlled to be turned on to apply an alternating magnetic field to the superconducting flux bridge, so that a DC voltage with the same direction as the secondary winding current is induced at both ends of the superconducting flux bridge.

[0023] In response to detecting that the parameter of the alternating current of the initial winding exceeds a first predetermined threshold range, sending a first control instruction to a regulating device connected to the first AC power source to adjust the operating parameter of the first AC power source, and

[0024] In response to detecting that the parameter of the alternating magnetic field exceeds a second predetermined threshold range, a second control instruction is sent to a regulating device connected to the second AC power source to adjust the operating parameter of the second AC power source.

[0025] According to the disclosed embodiment, the superconducting flux pump based on alternating magnetic field coupling is powered by an AC power supply. When the alternating magnetic field generated by the electromagnet acts on the current-carrying superconducting flux bridge, the pinning force of the superconducting material on the magnetic flux will be broken, and a dynamic resistance effect will be generated in the superconducting material. A DC voltage is induced at both ends of the superconducting flux bridge, and this voltage can excite the superconducting coil. At the same time, since the resistance of the superconducting coil is zero, the current excited in the superconducting coil by the voltage at both ends of the superconducting flux bridge will gradually accumulate, and the wireless excitation of the DC superconducting magnet running in a closed loop in a closed low-temperature system realizes flexible compensation of the magnetic field of the high-temperature superconducting magnet, and efficiently maintains the stability of the magnetic field of the closed-loop superconducting magnet. Compared with the method of directly exciting the high-temperature superconducting magnet with a DC power supply in the related examples, the excitation cost is effectively reduced and the excitation efficiency is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0027] Figure 1 A schematic diagram of the structure of a superconducting flux pump operating in a half-cycle based on alternating magnetic field coupling according to an embodiment of the present disclosure is shown;

[0028] Figure 2 A schematic diagram of the structure of a superconducting flux pump operating in a full cycle based on alternating magnetic field coupling according to an embodiment of the present disclosure is shown;

[0029] Figure 3 A schematic diagram of a superconducting magnetic flux system based on alternating magnetic field coupling provided in an embodiment of the present disclosure; and

[0030] Figure 4 A schematic diagram of a control method for a superconducting magnetic flux system based on alternating magnetic field coupling provided in an embodiment of the present disclosure.

[0031] Reference numerals:

[0032] 1. Transformer; 11. Primary winding; 12. First secondary winding; 13. First iron core; 14. First AC power supply; 15. Second secondary winding; 2. Superconducting flux bridge A; 6. Superconducting flux bridge B; 4. Superconducting coil; 31. Second iron core; 32. Second winding; 33. Second AC power supply; 3. Electromagnet A; 7. Electromagnet B; 71. Third iron core; 72. Third winding; 73. Third AC power supply; 5. Cryogenic container; 8. Controller; 9. Computer. DETAILED DESCRIPTION

[0033] In order to make the objectives, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0034] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0035] All terms used herein, including technical and scientific terms, have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification, and should not be interpreted in an idealized or overly rigid manner.

[0036] When using expressions such as "at least one of A, B, and C, etc.", it should generally be interpreted as the meaning of the expression generally understood by those skilled in the art. For example, "a system having at least one of A, B, and C" should include but not be limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc. When using expressions such as "at least one of A, B, or C, etc.", it should generally be interpreted as the meaning of the expression generally understood by those skilled in the art. For example, "a system having at least one of A, B, or C" should include but not be limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.

[0037] It should also be noted that the directional terms mentioned in the embodiments, such as "upper", "lower", "front", "back", "left", "right", etc., are only reference directions of the drawings and are not intended to limit the scope of protection of the present disclosure. Throughout the drawings, the same elements are represented by the same or similar reference numerals. Conventional structures or configurations will be omitted when they may cause confusion in the understanding of the present disclosure.

[0038] Since high-temperature superconducting magnets cannot operate in a closed-loop "continuous current mode", the relevant examples use a DC power supply to directly excite the high-temperature superconducting magnet. However, this method has the following problems: First, the excitation of superconducting magnets requires a large-capacity, high-performance DC power supply, which is expensive; second, the current lead connecting the DC power supply and the superconducting magnet needs to go from a room temperature environment to an ultra-low temperature environment, which introduces a large amount of heat into the low-temperature environment, increasing the burden on the refrigeration system.

[0039] In view of this, as one aspect of the present disclosure, a superconducting flux pump based on alternating magnetic field coupling is provided, comprising:

[0040] The transformer comprises a first core and a primary winding and a secondary winding wound around the first core, wherein the primary winding is connected to a first AC power source, and the secondary winding and a superconducting flux bridge form a first closed loop for providing an induced current corresponding to a current on the primary winding to the superconducting flux bridge.

[0041] an electromagnet, comprising a second core and a winding wound around the second core; the second winding is connected to a second AC power source and is used to apply an alternating magnetic field to the superconducting flux bridge so that a DC voltage is induced at both ends of the superconducting flux bridge, and

[0042] The superconducting coil and the superconducting flux bridge form a second closed loop to excite the superconducting coil using a DC voltage.

[0043] The specific components and structure of the superconducting flux pump based on alternating magnetic field coupling according to the embodiment of the present disclosure are described in detail below with reference to the accompanying drawings.

[0044] Figure 1 A schematic diagram of the structure of the half-cycle operation of a superconducting flux pump based on alternating magnetic field coupling provided in an embodiment of the present disclosure.

[0045] According to the embodiments of the present disclosure, Figure 1 As shown, the transformer (1) comprises a first iron core (13) and a primary winding (11) and a first secondary winding (12) wound around the first iron core (13), the primary winding (11) being connected to a first AC power source (14), the first secondary winding (12) and a superconducting flux bridge A (2) forming a first closed loop. The electromagnet A (3) comprises a second iron core (31) and a winding wound around the second iron core, the second winding (32) being connected to a second AC power source (33), and a superconducting coil (4) forming a second closed loop with the superconducting flux bridge.

[0046] According to the embodiments of the present disclosure, when the alternating magnetic field generated by the electromagnet acts on the current-carrying superconducting flux bridge, the pinning force of the superconducting material on the magnetic flux will be broken, and a dynamic resistance effect will be generated in the superconducting material, and a DC voltage will be induced at both ends of the superconducting flux bridge, which can excite the superconducting coil. At the same time, since the resistance of the superconducting coil is zero, the current excited in the superconducting coil by the voltage at both ends of the superconducting flux bridge will gradually accumulate until the target excitation current is reached.

[0047] According to an embodiment of the present disclosure, when the first AC power source (14) supplies power to the primary winding (11), the first secondary winding (12) generates an induced current, and the first secondary winding (12) and the superconducting flux bridge A (2) form a first closed loop. The function of the transformer (1) is to provide the superconducting flux bridge A (2) with an induced current corresponding to the current on the primary winding (11). When the second AC power source (33) supplies power to the second winding (32), the electromagnet A (3) applies an alternating magnetic field to the superconducting flux bridge A (2). When the superconducting flux bridge has both current passing through it and an alternating magnetic field applied to it, a DC voltage is induced at both ends. The induced voltage is in the same direction as the current. The superconducting flux bridge and the superconducting coil form a second closed loop. By charging the superconducting coil (4), the current of the superconducting coil (4) is gradually increased to reach the target excitation current, thereby realizing wireless excitation of a DC superconducting magnet operating in a closed loop in a closed cryogenic system.

[0048] According to the embodiments of the present disclosure, the above-mentioned superconducting flux pump is powered by an AC power supply, and uses an electromagnet to apply an alternating magnetic field to the superconducting flux bridge, thereby realizing wireless excitation of a DC superconducting magnet operating in a closed loop in a closed cryogenic system, greatly reducing the excitation cost, reducing the refrigeration burden of the cryogenic system, and efficiently maintaining the magnetic field stability of the superconducting magnet operating in a closed loop.

[0049] According to an embodiment of the present disclosure, the ratio of the number of turns of the primary winding to the number of turns of the secondary winding includes: 20:1~200:1. For example, it can be 20:1, 50:1, 100:1, 200:1, etc. The configuration of the number of turns ratio of the primary winding and the secondary winding realizes the flexible adjustment of the magnitude of the excitation current of the superconducting coil.

[0050] According to an embodiment of the present disclosure, the superconducting flux bridge, the secondary winding and the superconducting coil are all made of superconducting materials.

[0051] According to an embodiment of the present disclosure, the secondary winding, the superconducting flux bridge and the superconducting coil are disposed in a container at a predetermined temperature, and the predetermined temperature is less than the critical transition temperature of the superconducting material.

[0052] According to an embodiment of the present disclosure, the primary winding (11), the first AC power source (14), and the second AC power source (33) may be located inside the cryogenic container (5), or may be located outside the cryogenic container (5). The embodiment of the present disclosure does not specifically limit the positional relationship between the primary winding, the first AC power source, the second AC power source, and the cryogenic container.

[0053] According to the embodiments of the present disclosure, since the secondary winding, the superconducting flux bridge and the superconducting coil are arranged inside the cryogenic container, the superconducting flux pump based on alternating magnetic field coupling is powered by an AC power supply to realize wireless excitation of the DC superconducting magnet operating in a closed loop in a closed cryogenic system, thereby replacing the large-capacity DC power supply and current leads used in the traditional superconducting magnet excitation method, which can reduce the refrigeration burden of the cryogenic system and efficiently maintain the magnetic field stability of the closed-loop superconducting magnet.

[0054] According to an embodiment of the present disclosure, the superconducting flux bridge, the secondary winding and the superconducting coil are all in a superconducting state.

[0055] According to the embodiments of the present disclosure, a superconducting flux bridge in a superconducting state can generate a dynamic resistance effect under the action of an alternating magnetic field, and a DC voltage is induced at both ends of the superconducting flux bridge, which can excite a superconducting coil with zero resistance.

[0056] Figure 2 A schematic diagram of the structure of the full-cycle operation of a superconducting flux pump based on alternating magnetic field coupling provided in an embodiment of the present disclosure.

[0057] like Figure 2 As shown, the structure of the superconducting flux pump includes:

[0058] The transformer (1) comprises a first iron core (13) and a primary winding (11) wound around the first iron core (13), a first secondary winding (12) and a second secondary winding (15); the primary winding (11) is connected to a first AC power source (14).

[0059] The electromagnet A (3) comprises a second core (31) and a winding wound around the second core. The second winding (32) is connected to a second AC power source (33). For example, the electromagnet can be a positive magnet in the positive direction.

[0060] The electromagnet B (7) comprises a third core (71) and a winding wound around the third core, wherein the third winding (72) is connected to a third AC power source (73). For example, the electromagnet may be a reverse electromagnet, and the electromagnet B (7) is used to apply an alternating magnetic field to the superconducting flux bridge B (6).

[0061] The superconducting flux bridge A (2) and the superconducting flux bridge B (6) are respectively welded with the first secondary winding (12) and the second secondary winding (15) to form a closed loop. The second secondary winding (15) and the superconducting flux bridge B (6) form a third closed loop.

[0062] According to an embodiment of the present disclosure, when the primary winding (11) is connected to a first AC power source (14), the first secondary winding (12) and the second secondary winding (15) generate an induced current. When the second winding is connected to a second AC power source, an alternating magnetic field is applied to the superconducting flux bridge A (2), and the superconducting flux bridge A (2) is not only subjected to the induced current generated by the first secondary winding (12), but also subjected to an alternating magnetic field, so that a first DC voltage is induced at both ends of the superconducting flux bridge A (2). When the third winding is connected to a third AC power source, an alternating magnetic field is applied to the superconducting flux bridge B (6), and a second DC voltage is induced at both ends of the superconducting flux bridge B (6), so that current compensation of the superconducting coil (4) is achieved, a target excitation current is achieved, and excitation of the superconducting magnetic field is achieved.

[0063] According to an embodiment of the present disclosure, in a full-cycle flux pump, the mutual inductance direction between the first secondary winding (12) and the primary winding is opposite to the mutual inductance direction between the second secondary winding (15) and the primary winding.

[0064] According to an embodiment of the present disclosure, the first AC power source (14) can be in a continuous working state, and the second AC power source and the third AC power source can switch the working state according to the periodic change of the current of the primary winding.

[0065] For example, in the positive cycle of the current of the primary winding (11) connected to the first AC power source, the electromagnet A (3) applies an alternating magnetic field to the superconducting flux bridge A (2), and the electromagnet B (7) does not apply a magnetic field. In the negative cycle of the current of the primary winding (11), the electromagnet B (7) applies an alternating magnetic field to the superconducting flux bridge B (6), and the electromagnet A (3) does not apply a magnetic field. In the positive cycle of the current, the direction of the first DC voltage is the same as the positive current of the first AC power source, and in the negative cycle of the current, the direction of the second DC voltage is the same as the negative current of the first AC power source.

[0066] When an alternating current is passed through the primary winding of the transformer, the second alternating current power source and the third alternating current power source are alternately turned on in positive and negative cycles, thereby achieving current compensation for the superconducting coil (4) during the entire cycle of the operation of the first alternating current power source (14). The superconducting flux bridge A (2) and the superconducting flux bridge B (6) alternately charge the superconducting coil (4), shortening the excitation time and increasing the excitation efficiency.

[0067] According to the embodiment of the present disclosure, the number of electromagnets corresponds to the number of secondary windings and the number of flux bridges. The embodiment of the present disclosure does not specifically limit the number of transformer secondary windings, superconducting flux bridges, and electromagnets.

[0068] According to an embodiment of the present disclosure, the induction surface of the superconducting flux bridge is perpendicular to the magnetic induction direction of the alternating magnetic field.

[0069] According to the embodiments of the present disclosure, the size, structure, material, etc. of the transformer (1), electromagnet A (3) and electromagnet B (7) should be designed according to actual needs. The transformer (1) should be able to induce a current amplitude in the first secondary winding (12) and the second secondary winding (15) that is greater than the critical current of the superconducting coil (4). The electromagnet A (3) and the electromagnet B (7) should be able to provide sufficient magnetic field strength. The second core (31), the third core (71) and the first core (13) are made of high magnetic permeability materials, such as iron-based amorphous alloys.

[0070] According to an embodiment of the present disclosure, the above-mentioned flux pump may include two transformer secondary windings and two superconducting flux bridges. The mutual inductance formed by the two secondary windings and the primary winding is opposite in direction. Each secondary winding forms a closed loop with a superconducting flux bridge, and the current phase difference between the two secondary windings is 180°. Therefore, regardless of the positive cycle or negative cycle of the primary winding current, the direction of the current carried in the superconducting flux bridge is the same, and the direction of the voltage generated at both ends of the superconducting flux bridge is also the same. The direction of the voltage generated at both ends of the superconducting flux bridge is independent of the direction of the applied alternating magnetic field, and is the same as the direction of the current carried, thereby achieving continuous excitation of the superconducting coil.

[0071] Figure 3 Schematic diagram of a superconducting magnetic flux system based on alternating magnetic field coupling provided in an embodiment of the present disclosure.

[0072] like Figure 3 As shown, the superconducting flux system includes the above-mentioned superconducting flux pump, a controller (8) and a computer (9).

[0073] The controller (8) is connected to the first AC power source, the second AC power source and the third AC power source. When wireless excitation is performed, the first AC power source is always in a working state, and the controller controls the working state of the electromagnet according to the direction of the alternating current in the primary winding. When the primary winding (11) is in a positive cycle of the current, the controller controls the second AC power source to supply power, and the electromagnet A (3) enters a working state, applies an alternating magnetic field to the superconducting flux bridge A (2), and performs current compensation on the superconducting coil. When the primary winding (11) is in a negative cycle of the current, the controller causes the third AC power source to enter a working state, and the electromagnet B (7) applies an alternating magnetic field to the superconducting flux bridge B (6), and the electromagnet A (3) does not apply a magnetic field. The controller can also adjust the working parameters such as amplitude and frequency of the first AC power source, the second AC power source and the third AC power source.

[0074] According to an embodiment of the present disclosure, by controlling the power supply of an AC power source, the amplitude, frequency, waveform or phase of the alternating magnetic field of electromagnet A (3) and electromagnet B (7) can be changed for adjustment, or the amplitude, frequency or waveform of the alternating current in the primary winding (11) can be changed for adjustment, so as to control the average DC excitation voltage generated by the superconducting flux bridge A (2) and the superconducting flux bridge B (6), thereby realizing flexible compensation for the charging of the superconducting coil.

[0075] Figure 4 A schematic diagram of a control method for a superconducting flux pump based on alternating magnetic field coupling provided in an embodiment of the present disclosure.

[0076] like Figure 4 As shown, the control method of the superconducting flux system based on alternating magnetic field coupling of this embodiment includes operations S410 to S430.

[0077] In operation S410, it is detected that the direction of the initial winding alternating current is a predetermined direction, and the AC power supply corresponding to the predetermined direction is controlled to be turned on to apply an alternating magnetic field to the superconducting flux bridge, so that a DC voltage with the same direction as the secondary winding current is induced at both ends of the superconducting flux bridge.

[0078] In operation S420, it is detected that the parameter of the alternating current of the initial winding exceeds a first predetermined threshold range, and a first control instruction is sent to a regulating device connected to the first AC power source to adjust the operating parameter of the first AC power source.

[0079] In operation S430, it is detected that the parameter of the alternating magnetic field exceeds a second predetermined threshold range, and a second control instruction is sent to a regulating device connected to the second AC power source to adjust the operating parameter of the second AC power source.

[0080] According to an embodiment of the present disclosure, the transformer AC power supply is in a continuous working state, and the predetermined direction may be the direction of the alternating current of the primary initial winding.

[0081] For example: in the positive cycle of the current of the initial winding, the second AC power supply is controlled to be turned on to apply an alternating magnetic field to the superconducting flux bridge, and a DC voltage with the same direction as the secondary winding current is induced at both ends of the superconducting flux bridge to charge the superconducting coil. In the negative cycle of the current of the initial winding, the third AC power supply is controlled to be turned on to apply an alternating magnetic field to the superconducting flux bridge, and a DC voltage with the same direction as the secondary winding current is induced at both ends of the superconducting flux bridge to charge the superconducting coil. This realizes wireless excitation of a DC superconducting magnet operating in a closed loop in a closed cryogenic system.

[0082] According to an embodiment of the present disclosure, the operating parameters of the first AC power supply and the operating parameters of the second AC power supply can be dynamically adjusted according to the excitation requirements of the actual scenario.

[0083] According to an embodiment of the present disclosure, the parameters of the alternating current of the initial winding may include parameters such as current amplitude, frequency, and waveform, etc. The parameters of the alternating magnetic field may include parameters such as amplitude, frequency, and waveform of the alternating magnetic flux, etc.

[0084] According to an embodiment of the present disclosure, the first predetermined threshold range may be determined based on parameters such as the amplitude, frequency or waveform of the alternating magnetic field generated by the electromagnet. The second predetermined threshold range may be determined based on parameters such as the amplitude, frequency or waveform of the current of the initial winding, so as to achieve matching between the alternating magnetic field of the superconducting flux bridge and the current carried.

[0085] For example, when it is detected that the parameters of the alternating current of the initial winding exceed the first predetermined threshold range, the adjustment device can be used to adjust the working parameters of the first AC power supply so that the parameters of the alternating current of the initial winding are within the first predetermined threshold range.

[0086] For example, when it is detected that the parameters of the alternating magnetic field exceed the second predetermined threshold range, the adjustment device can be used to adjust the working parameters of the second AC power supply so that the parameters of the alternating magnetic field are within the second predetermined threshold range. According to the embodiment of the present disclosure, the control method of the superconducting flux pump based on alternating magnetic field coupling adjusts the magnitude of the superconducting coil compensation current by changing the parameters of the alternating current detected in the initial winding, thereby achieving control of the charging speed, shortening the charging waiting time, and improving the efficiency of wireless excitation.

[0087] The embodiments of the present disclosure are described above. However, these embodiments are only for illustrative purposes and are not intended to limit the scope of the present disclosure. Although the embodiments are described above separately, this does not mean that the measures in the various embodiments cannot be used in combination to advantage. The scope of the present disclosure is defined by the attached claims and their equivalents. Without departing from the scope of the present disclosure, those skilled in the art may make a variety of substitutions and modifications, which should all fall within the scope of the present disclosure.

Claims

1. A superconducting flux pump based on alternating magnetic field coupling, comprising: A transformer, comprising a first iron core and a primary winding and a secondary winding wound around the first iron core, wherein the primary winding is connected to a first AC power source, and the secondary winding and a superconducting flux bridge form a first closed loop for providing an induced current corresponding to a current on the primary winding to the superconducting flux bridge; An electromagnet, comprising a second core and a winding wound around the second core; the second winding is connected to a second AC power source and is used to apply an alternating magnetic field to the superconducting flux bridge so that a DC voltage is induced at both ends of the superconducting flux bridge; as well as a superconducting coil, forming a second closed loop with the superconducting flux bridge, so as to excite the superconducting coil by using the DC voltage; The electromagnet comprises: A forward electromagnet, comprising a second core and a winding wound around the second core; the second winding is connected to a second AC power supply and is used to apply an alternating magnetic field to the first superconducting flux bridge, so that a first DC voltage is induced at both ends of the first superconducting flux bridge; wherein a direction of the first DC voltage is the same as a forward current direction of the first AC power supply; A negative electromagnet comprises a third core and a winding wound around the third core; the third winding is connected to a third AC power supply and is used to apply an alternating magnetic field to the second superconducting flux bridge so that a second DC voltage is induced at both ends of the second superconducting flux bridge; wherein the direction of the second DC voltage is opposite to the negative current direction of the first AC power supply.

2. The superconducting flux pump according to claim 1, characterized in that: The number of the electromagnets corresponds to the number of the secondary windings and the number of the flux bridges.

3. The superconducting flux pump according to claim 2, characterized in that: The induction surface of the superconducting flux bridge is perpendicular to the magnetic induction direction of the alternating magnetic field.

4. The superconducting flux pump according to claim 1, characterized in that: The ratio of the number of turns of the primary winding to the number of turns of the secondary winding includes: 20:1~200:

1.

5. The superconducting flux pump according to any one of claims 1 to 4, characterized in that: The superconducting flux bridge, the secondary winding and the superconducting coil are all made of superconducting materials.

6. The superconducting flux pump according to claim 5, characterized in that: The secondary winding, the superconducting flux bridge and the superconducting coil are arranged in a container at a predetermined temperature; the predetermined temperature is less than the critical transition temperature of the superconducting material.

7. The superconducting flux pump according to claim 5, characterized in that: The superconducting flux bridge, the secondary winding and the superconducting coil are all in a superconducting state.

8. A superconducting flux system based on alternating magnetic field coupling, characterized in that: include: The superconducting flux pump and controller according to any one of claims 1 to 7, The controller is electrically connected to the first AC power source and the second AC power source, and is used to control the working state of the electromagnet according to the direction of the alternating current in the primary winding; and to adjust the working parameters of the first AC power source and the second AC power source.

9. A control method based on the system according to claim 8, characterized in that: In response to detecting that the direction of the alternating current of the initial winding is a predetermined direction, controlling the AC power source corresponding to the predetermined direction to be turned on to apply an alternating magnetic field to the superconducting flux bridge, so that a DC voltage having the same direction as the secondary winding current is induced at both ends of the superconducting flux bridge; In response to detecting that a parameter of the alternating current of the initial winding exceeds a first predetermined threshold range, sending a first control instruction to a regulating device connected to a first AC power source to adjust an operating parameter of the first AC power source; as well as In response to detecting that the parameter of the alternating magnetic field exceeds a second predetermined threshold range, a second control instruction is sent to a regulating device connected to a second AC power source to adjust an operating parameter of the second AC power source.

Images