A high-temperature superconducting switch device with closed-loop operation of a superconducting magnet and its use method

Abstract

The present invention provides a high-temperature superconducting switch device for closed-loop operation of a superconducting magnet and a method for use thereof, comprising a control magnet, a control magnet core, a high-temperature superconducting tape installed perpendicular to the plane of the control magnet's magnetic field, an insulating bracket, and an AC power supply. The control magnet is installed in the core, which is made of stacked silicon steel sheets or other materials that can reduce AC losses. The control magnet is externally connected to an AC power supply to generate an alternating magnetic field in the axial direction. The high-temperature superconducting tape is placed in a plane perpendicular to the magnetic field and fixed to the insulating bracket. The present invention achieves the function of rapid opening and closing of the circuit through the directional electric field generated by the high-temperature superconducting material under the AC magnetic field and the superconducting state restored to the superconducting material after the AC magnetic field is removed, thereby achieving closed-loop operation of the high-temperature superconducting magnet.

Description

Technical Field

[0001] The present invention relates to the technical field of superconducting magnets, and in particular to a high-temperature superconducting switch device for closed-loop operation of a superconducting magnet and a method for using the device. Background Art

[0002] Superconducting materials in their superconducting state exhibit properties such as zero resistance and the Meisner effect. Superconducting magnets made from these materials offer advantages such as high magnetic field strength and uniformity. With the recent development of high-temperature superconducting materials, high-temperature superconducting magnets have gradually come into the spotlight. Compared to low-temperature superconducting magnets, high-temperature superconducting magnets can operate at higher temperatures and possess higher critical field strengths. A representative example is the yttrium barium copper oxide (YBCO) high-temperature superconducting material.

[0003] Closed-loop operation utilizes the zero-resistance characteristics of superconducting magnets to maintain a stable current flow even after the external power supply is disconnected. High-temperature superconducting coils in closed-loop operation maintain excellent magnetic field stability for extended periods, unaffected by losses caused by current leads. This is a key technology for superconducting magnets.

[0004] Commonly used superconducting switches can be divided into three types: thermally controlled, current-controlled, and magnetic-field-controlled. Thermally controlled switches operate by heating a superconductor above its critical temperature, causing it to quench and close. However, a disadvantage of thermally controlled switches is their long switching times (typically several seconds or more). Current-controlled switches operate by increasing the current through the switch to exceed the superconductor's critical current, causing it to close. However, these frequent quenches can degrade switch performance. Summary of the Invention

[0005] In response to the closed-loop operation conditions required for high-temperature superconducting magnets, the present invention provides a high-temperature superconducting switch device and a method of use for closed-loop operation of superconducting magnets. The device realizes the function of rapid opening and closing of the circuit through the directional electric field generated by the high-temperature superconducting material under the AC magnetic field and the superconducting state restored by the superconducting material after the AC magnetic field is removed, thereby realizing the closed-loop operation of the high-temperature superconducting magnet.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] A high-temperature superconducting switch device with a superconducting magnet operating in a closed loop comprises a control magnet, an iron core, a high-temperature superconducting tape mounted on a plane perpendicular to the control magnet's magnetic field direction, an insulating bracket, and an AC power supply. The control magnet is connected to the AC power supply to generate an alternating magnetic field in the axial direction. The high-temperature superconducting tape is fixed to the insulating bracket. The control magnet is divided into two layers, upper and lower, and fixed to the iron core via an intermediate insulating bracket. The iron core is a symmetrical double-E-shaped iron core centered on the insulating bracket, with a circular central column. The control magnet is wound and connected to the central column of the iron core. The high-temperature superconducting magnet is connected to an excitation power supply to generate an excitation effect during the excitation phase of the high-temperature superconducting magnet.

[0008] Furthermore, the iron core is made of stacked silicon steel sheets, thereby reducing AC loss; the iron core is a symmetrical double E-shaped iron core centered on the insulating bracket.

[0009] Furthermore, the insulating bracket and the control magnet are fastened with bolts or fixed with glue.

[0010] Furthermore, the high-temperature superconducting switch device is provided with a potential signal line to measure the generated directional voltage to determine the dynamic resistance of the high-temperature superconducting switch device.

[0011] Furthermore, the control magnet is in a solenoid shape to generate a vertical field strength on the surface of the high temperature superconducting switch device.

[0012] The present invention also provides a method for using a high-temperature superconducting switch device with a superconducting magnet in closed-loop operation, comprising:

[0013] Preparation stage: Weld the high-temperature superconducting tape used as the superconducting switch in parallel with the high-temperature superconducting magnet that needs to operate in a closed loop, and connect the control magnet to an external AC power supply;

[0014] Cooling stage: Cooling the high-temperature superconducting magnets and high-temperature superconducting switch devices that need to be operated in a closed loop to below the superconducting critical transition temperature;

[0015] Excitation stage: Use the excitation power supply to energize the high-temperature superconducting magnet that needs to operate in a closed loop. At this time, turn on the AC power supply to control the magnet to generate an alternating magnetic field on the high-temperature superconducting tape serving as the superconducting switch. The induced electric field hinders the current from flowing through the high-temperature superconducting switch device. At this time, the high-temperature superconducting switch device is in the disconnected state.

[0016] Closed-loop stage: After the high-temperature superconducting magnet that needs to operate in a closed loop reaches the required operating current, the excitation power supply is turned off and the AC power supply connected to the control magnet is turned off. At this time, the high-temperature superconducting tape serving as the superconducting switch recovers the superconducting state, the high-temperature superconducting switch device is in the open state, and the high-temperature superconducting magnet achieves closed-loop operation.

[0017] The beneficial effects of the present invention compared to the prior art are:

[0018] The AC magnetically controlled high-temperature superconducting switch has a short opening and closing time (milliseconds) and a response speed much faster than that of a traditional thermally controlled superconducting switch. The control magnet used in the AC magnetically controlled high-temperature superconducting switch requires a small magnetic field strength, and does not require the high magnetic field strength required by traditional magnetically controlled superconducting switches to cause magnetic field quenching. Moreover, the opening and operation of the switch will not cause performance degradation of the superconducting material itself, which serves as the high-temperature superconducting switch. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] To more clearly illustrate the embodiments of the present invention, the accompanying drawings are now provided. A person skilled in the art will readily appreciate various other advantages and benefits from reading the detailed description of the preferred embodiments below. The accompanying drawings are provided for illustration purposes only and are not to be construed as limiting the present invention.

[0020] Figure 1 A schematic diagram of the control magnet and insulating bracket of the present invention;

[0021] Figure 2 A schematic diagram of a high-temperature superconducting switch device of the present invention connected to a high-temperature superconducting magnet;

[0022] Figure 3 This is a schematic diagram of the present invention in an example of closed-loop operation of a high-temperature superconducting magnet.

[0023] Figure 4 It is a schematic diagram of the upper half of the iron core of the present invention;

[0024] In the accompanying drawings: 1-control magnet; 2-iron core; 3-high-temperature superconducting tape; 4-insulating bracket; 5-AC power supply; 6-high-temperature superconducting magnet; 7-excitation power supply. DETAILED DESCRIPTION

[0025] Examples of the present invention are described in detail below with reference to the accompanying drawings. The present disclosure may be implemented in various forms and should not be limited by the embodiments described herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0026] like Figure 1-4As shown, the high-temperature superconducting switch device of the present invention includes a control magnet 1, an iron core 2, a high-temperature superconducting tape 3, an insulating support 4, and an AC power supply 5. The control magnet 1 is typically wound with copper wire and contains silicon steel sheets or other materials to reduce AC losses. The high-temperature superconducting tape 3, which serves as a superconducting switch, is placed on a plane perpendicular to the magnetic field direction of the control magnet 1. The control magnet 1 is externally connected to the AC power supply 5 to generate an alternating magnetic field in the axial direction. The high-temperature superconducting tape 3 is fixed to the insulating support 4. The control magnet 1 is divided into two layers, upper and lower, and fixed to the iron core 2 via the intermediate insulating support 4. The iron core 2 is a symmetrical double E-shaped iron core centered on the insulating support 4. The central column of the iron core 2 is circular, and the control magnet 1 is wound and connected to the iron core 2 through the central column. The high-temperature superconducting magnet 6 is externally connected to the excitation power supply 7 to generate the excitation effect during the excitation phase of the high-temperature superconducting magnet 6.

[0027] like Figure 2 As shown, the high-temperature superconducting switch device of the present invention is connected to the high-temperature superconducting magnet 6, usually by welding, and is connected in parallel at both ends of the high-temperature superconducting magnet.

[0028] like Figure 3 As shown, the high-temperature superconducting magnet 6 is powered by an excitation power supply 7, the high-temperature superconducting switch device is connected in parallel with the high-temperature superconducting magnet 6, and the control magnet 1 is energized by the AC power supply 5 to achieve the opening and closing effects of the high-temperature superconducting switch device.

[0029] like Figure 4 As shown, the central column of the iron core 2 is circular.

[0030] The use of the high-temperature superconducting switch device in the present invention is divided into four stages:

[0031] Preparation stage: The high-temperature superconducting tape 3 serving as the superconducting switch is welded in parallel to the high-temperature superconducting magnet 6 that requires closed-loop operation, and the control magnet 1 is connected to an external AC power supply 5;

[0032] Cooling stage: cooling the high-temperature superconducting magnet 6 that needs to be operated in a closed loop to below the superconducting critical transition temperature;

[0033] Excitation stage: Use the excitation power supply 7 to energize the high-temperature superconducting magnet 6 that needs to operate in a closed loop. At this time, turn on the AC power supply 5 to control the magnet 1 to generate an alternating magnetic field on the high-temperature superconducting tape 3 serving as the superconducting switch. The induced electric field blocks the current from flowing through the high-temperature superconducting switch device. At this time, the high-temperature superconducting switch device is in the disconnected state.

[0034] Closed-loop stage: After the high-temperature superconducting magnet 6 that needs to operate in a closed loop reaches the required operating current, the excitation power supply 7 is turned off and the AC power supply 5 connected to the control magnet 1 is turned off. At this time, the high-temperature superconducting tape 3 serving as the superconducting switch recovers the superconducting state, the high-temperature superconducting switch device is in the open state, and the high-temperature superconducting magnet 6 achieves closed-loop operation.

[0035] The principle behind the AC magnetically controlled high-temperature superconducting switching device employed in this invention is that when a type II superconductor carrying a DC current is subjected to a perpendicular AC magnetic field, a directional electric field is generated. The applied AC magnetic field redistributes eddy currents within the superconductor, resulting in a net flux flowing from one side of the sample to the other, which, on a macroscopic scale, is equivalent to dynamic resistance.

[0036] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high-temperature superconducting switch device with a superconducting magnet in closed-loop operation, characterized in that: The invention comprises a control magnet (1), an iron core (2), a high-temperature superconducting tape (3) mounted on a plane perpendicular to the magnetic field direction of the control magnet (1), an insulating bracket (4) and an AC power supply (5); the control magnet (1) is externally connected to the AC power supply (5) to generate an alternating magnetic field in the axial direction; the high-temperature superconducting tape (3) is fixed on the insulating bracket (4); the control magnet (1) is divided into two layers, upper and lower, by the insulating bracket (4) in the middle and fixed on the iron core (2); the iron core (2) is a symmetrical double E-shaped iron core centered on the insulating bracket (4), the central column of the iron core (2) is circular, and the control magnet (1) is wound on the central column of the iron core (2); the high-temperature superconducting magnet (6) is externally connected to the excitation power supply (7) to generate an excitation effect on the excitation stage of the high-temperature superconducting magnet (6).

2. A high-temperature superconducting switch device with a superconducting magnet in closed-loop operation according to claim 1, characterized in that: The iron core (2) is made of stacked silicon steel sheets, thereby reducing AC losses.

3. A high-temperature superconducting switch device with closed-loop superconducting magnet operation according to claim 1, characterized in that: The insulating bracket (4) and the control magnet (1) are fastened with bolts or fixed with glue.

4. A high-temperature superconducting switch device with a superconducting magnet in closed-loop operation according to claim 1, characterized in that: The high-temperature superconducting switch device is provided with a potential signal line to measure the generated directional voltage so as to determine the dynamic resistance of the high-temperature superconducting switch device.

5. The high-temperature superconducting switch device with closed-loop superconducting magnet operation according to claim 1, characterized in that: The control magnet (1) is in a solenoid shape to generate a vertical field strength on the surface of the high-temperature superconducting switch device.

6. A method for using a high-temperature superconducting switch device with a superconducting magnet in closed-loop operation according to any one of claims 1 to 5, characterized in that: include: In the preparation stage, a high-temperature superconducting tape (3) serving as a superconducting switch is welded in parallel to a high-temperature superconducting magnet (6) that requires closed-loop operation, and the control magnet (1) is connected to an external AC power supply (5); In the cooling stage, the high-temperature superconducting magnet (6) and the high-temperature superconducting switch device that need to be operated in a closed loop are cooled to below the superconducting critical transition temperature; In the excitation stage, an excitation power supply (7) is used to excite and energize a high-temperature superconducting magnet (6) that needs to be operated in a closed loop. At this time, the AC power supply (5) is turned on to control the magnet (1) to generate an alternating magnetic field on the high-temperature superconducting tape (3) serving as a superconducting switch, thereby inducing an electric field that hinders the current from flowing through the high-temperature superconducting switch device. At this time, the high-temperature superconducting switch device is in an off state. In the closed-loop stage, after the high-temperature superconducting magnet (6) that needs to be operated in a closed-loop state reaches the required operating current, the excitation power supply (7) is turned off and the AC power supply (5) connected to the control magnet (1) is turned off. At this time, the high-temperature superconducting strip (3) serving as the superconducting switch recovers the superconducting state, the high-temperature superconducting switch device is in the open state, and the high-temperature superconducting magnet (6) realizes closed-loop operation.

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