A dynamic resistance testing device and method for high-temperature superconducting cable superconducting tape

Abstract

The present invention discloses a dynamic resistance testing device and method for a high-temperature superconducting cable superconducting tape, which belongs to the technical field of superconducting tapes, and includes a power supply component, a sensor component, and an electromagnet component. A superconducting tape is also arranged inside the sensor component; the power supply component includes a DC power supply and an AC power supply; the sensor component includes a Hall patch; the electromagnet component includes a winding coil and a magnet; both winding coils are connected to the AC power supply; a control component is provided, and the control component can adjust the current of the AC power supply. Through the present invention, the Hall patch is connected to a multimeter, and the dynamic resistance of the superconducting tape under different magnetic fields and current conditions can be detected in real time, providing high-precision test data. The electromagnet component is provided with a winding coil and a magnet. The two winding coils and the magnet form an electromagnetic induction device, which is connected to the AC power supply, and the magnetic field can be controlled by adjusting the size, frequency and other parameters of the AC power supply.

Description

Technical Field

[0001] The invention relates to a dynamic resistance testing device and method for a high-temperature superconducting cable superconducting tape, belonging to the field of superconducting technology testing and measurement, and specifically to the technical field of high-temperature superconducting material performance detection. Background Art

[0002] The second generation of high temperature superconducting tape (REBCO tape) has been widely used in the field of high temperature superconducting technology in recent years due to its excellent current carrying capacity, mechanical properties and high cost performance. This type of material has gradually become the core material in a variety of advanced equipment such as high temperature superconducting cables, motors, magnets, etc. However, in actual use, especially in the operating environment of high temperature superconducting cables, superconducting tapes will be affected by the complex electromagnetic environment, resulting in the phenomenon of "dynamic resistance".

[0003] When a high-temperature superconducting cable transmits direct current, there is often an external alternating magnetic field around the tape. This magnetic field will induce a direct current electric field in the same direction as the direct current inside the tape, forming a dynamic resistance. Specifically, the existence of dynamic resistance will lead to the following effects: 1. Cable loss increases, and dynamic resistance reduces the transmission efficiency of the superconducting tape, and the lost energy is released in the form of heat; 2. Heat accumulation will cause the temperature of the tape to rise, increasing the refrigeration burden of the cryogenic system; 3. The increase in temperature will cause the superconducting tape to gradually lose its superconducting ability, resulting in cable failure; 4. The damage to the superconducting tape may cause large-scale equipment downtime and economic losses.

[0004] In order to ensure the feasibility and operating efficiency of high-temperature superconducting cables, the dynamic resistance characteristics of superconducting tapes must be accurately measured. At present, there are certain problems in the dynamic resistance test of superconducting tapes, including low test accuracy, high complexity of the test device, and inability to fully simulate actual operating conditions. Therefore, there is an urgent need for a dynamic resistance test device and method for superconducting tapes of high-temperature superconducting cables. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a dynamic resistance testing device and method for high-temperature superconducting cable superconducting tape, which solves the current problems of low accuracy in dynamic resistance detection of superconducting tapes, great complexity of the testing device, and inability to fully simulate actual use conditions.

[0006] The technical problem to be solved by the present invention is achieved by adopting the following technical solution: a dynamic resistance test device for high-temperature superconducting cable superconducting tape, comprising:

[0007] Power supply components, sensor components, electromagnet components,

[0008] The power supply component is connected to the sensor component or the electromagnet component, and a superconducting tape is also arranged inside the sensor component;

[0009] The power supply assembly includes a DC power supply and an AC power supply; the sensor assembly includes a Hall patch; the electromagnet assembly includes a winding coil and a magnet;

[0010] The magnet is rectangular, and the two winding coils are symmetrically arranged on two sides of the magnet;

[0011] Both ends of the superconducting tape are connected to the DC power supply, and the Hall patch is arranged on the surface of the superconducting tape;

[0012] The two winding coils are both connected to the AC power source;

[0013] A control component is also provided, which is connected to the AC power supply and can adjust the current of the AC power supply.

[0014] Preferably, a notch is provided in the middle of one side of the magnet where the winding coil is not provided, and the superconducting tape is provided in the middle of the notch.

[0015] Preferably, the DC power supply is capable of outputting a constant current.

[0016] Preferably, the control component can adjust the AC power supply to change the magnetic field size of the electromagnet component.

[0017] Preferably, the control component includes a programmable calculator and a multimeter, the programmable calculator can adjust the size of the AC power supply, and the multimeter is connected to the Hall patch.

[0018] Preferably, the multimeter can detect the voltage of the Hall patch.

[0019] A method for testing the dynamic resistance of a high-temperature superconducting cable superconducting tape, preferably,

[0020] Step 1: Fix the winding coil on the magnet, and connect the winding coil to the AC power supply;

[0021] Step 2: connecting the two ends of the superconducting tape to the DC power supply, setting the Hall patch on the surface of the superconducting tape, and connecting the Hall patch to the multimeter;

[0022] Step 3: Connecting the programmable calculator to the AC power supply;

[0023] Step 4: Except for the power supply component and the control component, the remaining parts are placed in liquid nitrogen at 7.2K to 77.4K;

[0024] Step 5: Adjust the output current value of the DC power supply to 100A;

[0025] Step 6: Control the programmable computer to adjust the output of the AC power supply, adjust the magnetic pole strength of the electromagnet assembly to 0-200mT and the frequency to 50Hz;

[0026] Step 7: Use the multimeter to test the voltage of the Hall patch under different magnetic fields;

[0027] Step 8: Calculate the DC transmission current I of the superconducting tape under different magnetic field intensities according to the parameters of the Hall patch.

[0028] The beneficial effects of the present invention are:

[0029] (1) According to the present invention, a power supply component, a sensor component, an electromagnet component, and a control component are provided in the device, wherein the sensor component includes a Hall patch, and the Hall patch can be connected to a multimeter in the control component. Through the combination of the Hall patch and the multimeter, the dynamic resistance of the superconducting tape under different magnetic fields and current conditions can be detected in real time, providing high-precision test data. The electromagnet component is provided with a winding coil and a magnet. The two winding coils and the magnet form an electromagnetic induction device, which is connected to an AC power supply, and the magnetic field can be controlled by adjusting the size, frequency and other parameters of the AC power supply.

[0030] (2) Through the present invention, during the detection process, by simultaneously applying direct current and alternating current magnetic field, wherein the direct current is provided by a direct current power supply and the alternating current magnetic field is provided by an alternating current power supply, the resistance of the superconducting tape in a complex working environment can be simulated. The test device is mainly composed of common electronic components and equipment, and the hardware structure is simple and easy to build. The alternating current power supply is controlled by a programmable computer to modify the magnetic field of the electromagnet assembly, thereby reducing the error of manual operation and improving the test efficiency.

[0031] (3) Through the present invention, the data of the AC power supply and the Hall patch can be transmitted to a programmable computer to realize the control of data acquisition and power supply components. The device can be applied to superconducting tapes of different models and specifications and has good versatility. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the device connection structure of the present invention.

[0033] In the figure: 1-superconducting tape, 2-head end, 3-tail end, 4-Hall patch, 5-winding coil 1, 6-winding coil 2, 7-magnet, 8-DC power supply, 9-AC power supply, 10-programmable computer, 11-multimeter. DETAILED DESCRIPTION

[0034] In order to make the technical means, creative features, objectives and effects of the present invention easier to understand, the present invention is further described below in conjunction with specific embodiments.

[0035] Example 1

[0036] like Figure 1 As shown, a dynamic resistance testing device for high-temperature superconducting cable strips includes:

[0037] A power supply component, a sensor component, an electromagnet component, and a control component. The power supply component is connected to the sensor component or the electromagnet component. A superconducting tape 1 is also arranged inside the sensor component.

[0038] Reference Figure 1 The power supply component includes a DC power supply 8 and an AC power supply 9; the sensor component includes a Hall patch 4; the electromagnet component includes a winding coil 1 5, a winding coil 2 6, and a magnet 7. The DC power supply 8 is connected to the sensor component, and the AC power supply 9 is connected to the electromagnet component.

[0039] In this embodiment, the magnet 7 of the electromagnet assembly is rectangular, and winding coil 1 5 and winding coil 2 6 are symmetrically arranged on both sides of the rectangle. A gap is arranged in the middle of one side of the magnet 7 where winding coil 1 5 and winding coil 2 6 are not arranged, and the superconducting tape 1 is arranged in the middle of the gap of the magnet 7.

[0040] The two ends of the superconducting tape 1 are divided into a head end 2 and a tail end 3, wherein the two ends of the DC power supply 8 are provided with wires respectively connected to the head end 2 and the tail end 3 of the superconducting tape 1. A Hall patch 4 is also provided in the middle of the superconducting tape 1, and the Hall patch 4 is provided on a side close to the tail end 3 and is not in the gap of the magnet 7.

[0041] The AC power supply 9 is provided with two wires, which are respectively connected to the winding coil 1 5 and the winding coil 2 6; the other end of the AC power supply 9 is connected to the control component, and the control component can adjust the magnetic field size of the electromagnet component by adjusting the output current of the AC power supply 9. In this embodiment, the multimeter 11 is connected to the Hall patch 4, and the multimeter 11 can detect the voltage of the Hall patch 4. The data detected by the multimeter 11 can be transmitted to the programmable computer 10.

[0042] The programmable calculator 10 can calculate the size of the dynamic resistance in the superconducting tape according to the set current output by the DC power supply 8, the voltage of the Hall patch 4 set on the superconducting tape 1 detected by the multimeter 11, and the magnetic field strength output by the electromagnet assembly.

[0043] A dynamic resistance test method for high-temperature superconducting cable superconducting tape, the specific test method is as follows:

[0044] Step 1: Fix the winding coil 1 5 and the winding coil 2 6 on the magnet 7, and connect the AC power supply 9 to the winding coil 1 5 and the winding coil 2 6 respectively.

[0045] Step 2: Connect the head end 2 and the tail end 3 of the superconducting tape 1 to a DC power supply 8 through wires, and arrange a Hall patch 4 on the surface of the superconducting tape 1 , and connect the other end of the Hall patch 4 to a multimeter 11 .

[0046] Step 3: Connect the programmable calculator 10 to the AC power supply 9 . The programmable calculator 10 can control the output of the AC power supply 9 , and the data detected by the multimeter 11 can be transmitted to the programmable calculator 10 .

[0047] Step 4: Except for the power supply component and the control component, the rest of the device is placed in liquid nitrogen at 7.2K to 77.4K.

[0048] Step 5: Adjust the output current of the DC power supply to 100A.

[0049] Step 6: Control the programmable calculator 10 to adjust the output of the AC power supply 9. By adjusting the output of the AC power supply 9, the magnetic pole strength of the electromagnet assembly is controlled to be 0-200mT and the frequency to be 50Hz.

[0050] Step 7: Use the multimeter 11 to test the voltage detected by the Hall patch 4 on the superconducting tape 1 under different magnetic fields.

[0051] Step 8: Based on the data detected by the Hall patch 4, the multimeter 11 transmits the data detected by the Hall patch 4 to the programmable calculator 10, and calculates the DC transmission current I of the superconducting tape 1 under different magnetic field intensities based on the detected parameters.

[0052] A method for calculating the dynamic resistance of a superconducting tape 1 is provided:

[0053] When the amplitude of the component of the external alternating magnetic field perpendicular to the surface of the strip exceeds a certain threshold, the magnetic flux movement will be triggered, and some magnetic flux quanta will enter from one side of the superconducting strip, pass through the central area where the DC current flows, and finally exit from the other side of the superconducting strip. In each cycle of the alternating magnetic field, a certain amount of magnetic flux will pass through the center of the superconducting strip, that is, the area where the DC transmission current flows, and transfer from one side of the superconductor to the other side. At this time, the superconducting strip will generate a DC voltage along the direction of current transmission. Since the voltage is consistent with the direction of the DC load current, a transmission loss will be generated. A virtual resistor can be introduced to equalize the transmission loss. Therefore, this phenomenon is called the "dynamic resistance effect", the virtual resistor is called the "dynamic resistor", and the transmission loss is called the "dynamic resistance loss".

[0054] pass:

[0055]

[0056] The normalized current i of the superconducting tape 1 is calculated, where I is the DC transmission current of the superconducting tape 1 and I′ is the self-field critical current of the superconducting tape 1 when it leaves the factory.

[0057] Further:

[0058]

[0059] In this formula, the magnetic field intensity B1 of the superconducting tape 1 is calculated, D is the width of the superconducting tape 1, and μ is the magnetic permeability;

[0060] For the “dynamic resistance” in the superconducting tape 1, we have:

[0061]

[0062] The dynamic resistance R of the superconducting tape 1 can be calculated, B is the magnitude of the external AC magnetic field, and f is the frequency of the AC magnetic field.

[0063] In this embodiment, the programmable calculator 10 controls the output of the AC power supply 9 at step 6 to adjust the stimulation intensity of the electromagnet assembly to 30mT, 40mT, 50mT, and the frequency to 50Hz. It can be obtained by calculation that the dynamic resistance R of the superconducting tape 1 at the magnetic field magnitudes of 30mT, 40mT, and 50mT is: 2.67μΩ / m, 23.47μΩ / m, and 33.04μΩ / m.

[0064] The basic principles, main features and advantages of the present invention are shown and described above. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A dynamic resistance test device for high-temperature superconducting cable superconducting tape, comprising: Power supply components, sensor components, electromagnet components, The power supply component is connected to the sensor component or the electromagnet component, and a superconducting tape is also arranged inside the sensor component; Features: The power supply assembly includes a DC power supply and an AC power supply; the sensor assembly includes a Hall patch; the electromagnet assembly includes a winding coil and a magnet; The magnet is rectangular, and the two winding coils are symmetrically arranged on two sides of the magnet; Both ends of the superconducting tape are connected to the DC power supply, and the Hall patch is arranged on the surface of the superconducting tape; The two winding coils are both connected to the AC power source; A control component is also provided, which is connected to the AC power supply and can adjust the current of the AC power supply.

2. The dynamic resistance testing device for high-temperature superconducting cable superconducting tape according to claim 1, characterized in that: A notch is provided in the middle of one side of the magnet where the winding coil is not provided, and the superconducting tape is provided in the middle of the notch.

3. The dynamic resistance testing device for high-temperature superconducting cable superconducting tape according to claim 1, characterized in that: The DC power supply can output a constant current.

4. The dynamic resistance testing device for high-temperature superconducting cable superconducting tape according to claim 1, characterized in that: The control component can adjust the AC power supply to change the magnetic field size of the electromagnet component.

5. The dynamic resistance testing device for high-temperature superconducting cable superconducting tape according to claim 1, characterized in that: The control component includes a programmable calculator and a multimeter. The programmable calculator can adjust the size of the AC power supply, and the multimeter is connected to the Hall patch.

6. The dynamic resistance testing device for high-temperature superconducting cable superconducting tape according to claim 5, characterized in that: The multimeter can detect the voltage of the Hall patch.

7. A method for testing the dynamic resistance of a high-temperature superconducting cable superconducting tape, wherein the method is implemented by using a dynamic resistance testing device for a high-temperature superconducting cable superconducting tape according to any one of claims 1 to 6, and wherein: Step 1: Fix the winding coil on the magnet, and connect the winding coil to the AC power supply; Step 2: connecting the two ends of the superconducting tape to the DC power supply, setting the Hall patch on the surface of the superconducting tape, and connecting the Hall patch to the multimeter; Step 3: Connecting the programmable calculator to the AC power supply; Step 4: Except for the power supply component and the control component, the remaining parts are placed in liquid nitrogen at 7.2K to 77.4K; Step 5: Adjust the output current value of the DC power supply to 100A; Step 6: Control the programmable computer to adjust the output of the AC power supply, and adjust the magnetic pole strength of the electromagnet assembly to 0-200 mT and the frequency to 50 Hz; Step 7: Use the multimeter to test the voltage of the Hall patch under different magnetic fields; Step 8: Calculate the DC transmission current I of the superconducting tape under different magnetic field intensities according to the parameters of the Hall patch.

Images