A test device and method for the intrinsic energy consumption of a high-temperature superconducting flux pump

Abstract

The present invention discloses a test device and method for the intrinsic energy consumption of a high-temperature superconducting flux pump, which includes a cooling box, a superconducting component, and a permanent magnet component. The superconducting component is located inside the cooling box. The permanent magnet component includes a rotating shaft and a permanent magnet flywheel, and the permanent magnet flywheel is provided on the rotating shaft. The present invention utilizes the cooperation of the permanent magnet component and the superconducting component, and uses the rotation of the permanent magnet flywheel to generate a traveling magnetic field wave, which acts on the stator short tape to generate a direct current in the closed-loop circuit for brushless excitation of the superconducting coil. In the experimental method, by measuring the mechanical-electromagnetic conversion energy and subtracting the excitation energy, the joint resistance energy consumption, and the HTS tape dynamic resistance energy consumption, the value of the intrinsic energy consumption is obtained. By cooperating with the corresponding theoretical calculation method to calculate the objectively existing physical quantity of the intrinsic energy consumption, the internal physical mechanism of the intrinsic energy consumption is analyzed and determined, and it is determined that the action of the traveling magnetic field wave is the fundamental reason for generating the intrinsic energy consumption in the stator short tape.

Description

Technical Field

[0001] The present invention relates to the technical field of superconducting tapes, and particularly to a test device and method for the intrinsic energy consumption of a high-temperature superconducting flux pump. Background Art

[0002] High-temperature superconducting (HTS) synchronous motors have broad application prospects. However, the n value of HTS materials is low, and the superconducting joint technology still needs to be developed. The superconducting rotor magnet in a low-temperature environment still needs to be excited from the outside through current leads, resulting in Joule heat and leakage heat, increasing the refrigeration load. The HTS flux pump can excite the magnet without mechanical contact between the closed-loop superconducting magnet and the normal-temperature environment, replacing the current leads, and has become a research hotspot in recent years. A large amount of experimental data and HTS motor designs based on the flux pump have been reported. However, based on its working principle, there are dynamic resistance and flux movement in the HTS short tape (stator) in the flux pump, inevitably generating energy consumption, namely the so-called intrinsic energy consumption.

[0003] In recent years, through the research on HTS flux pumps at home and abroad, the excitation effect on the magnetic field of the HTS magnet closed-loop circuit has been demonstrated experimentally, and beneficial explorations have been carried out on the phenomenon theory. Based on this, the designs of HTS synchronous motors and rotors with brushless excitation based on HTS flux pumps have been carried out. However, the "intrinsic energy consumption" problem of HTS flux pumps during the excitation process has not received attention. In the limited reports, only the Joule heat generated by the dynamic resistance of the HTS short tape (stator) and its impact on the load of the entire cooling system have been mainly considered. Based on the working principle of the HTS flux pump, the dynamic resistance and flux movement in the HTS short tape caused by the alternating magnetic field, resulting in Joule heat and hysteresis loss, may all be non-negligible components of the intrinsic energy consumption of the HTS flux pump. Moreover, this energy consumption will directly lead to the temperature rise of the HTS short tape (stator) and the instability of the working state, thus affecting the technical advantages and corresponding practical value of the HTS flux pump compared with conventional current leads. Therefore, the present invention proposes a test device and method for the intrinsic energy consumption of a high-temperature superconducting flux pump to solve the problems existing in the prior art. Summary of the Invention

[0004] Aiming at the above problems, the purpose of the present invention is to propose a test device and method for the intrinsic energy consumption of a high-temperature superconducting flux pump. The device and method analyze and determine the internal physical mechanism of the intrinsic energy consumption, and determine that the action of the traveling magnetic field wave is the fundamental reason for the generation of intrinsic energy consumption in the stator short tape, which has very high practical value for the research of HTS flux pump technology.

[0005] To achieve the objectives of the present invention, the present invention is realized through the following technical solutions: A test device for the intrinsic energy consumption of a high-temperature superconducting flux pump, comprising a cooling box, a superconducting component, and a permanent magnet component. The superconducting component is located inside the cooling box. The permanent magnet component includes a rotating shaft and a permanent magnet flywheel. The permanent magnet flywheel is provided on the rotating shaft. The superconducting component includes a superconducting coil, HTS joints, and stator short tapes. The superconducting coil is arranged inside the cooling box and is wound by HTS tapes. The two ends of the superconducting coil are HTS joints, and stator short tapes are connected to the two ends of the HTS joints. The permanent magnet flywheel is adjacent to the stator short tapes.

[0006] A further improvement lies in that: Liquid nitrogen refrigerant is filled inside the cooling box.

[0007] A further improvement lies in that: A bracket is provided on the superconducting coil, and the bracket is fixed to the bottom inside the cooling box.

[0008] A further improvement lies in that: There is a gap between the superconducting component and the permanent magnet component and they do not contact each other.

[0009] A further improvement lies in that: The superconducting coil, HTS joints, and stator short tapes form a closed-loop energized circuit.

[0010] A test method for the intrinsic energy consumption of a high-temperature superconducting flux pump comprises the following steps:

[0011] Step 1: Place the superconducting component and the permanent magnet component in the low-temperature environment of the liquid nitrogen refrigerant, rotate the rotating shaft to drive the permanent magnet flywheel to rotate, generate a traveling magnetic field wave, and the traveling magnetic field wave performs brushless excitation on the superconducting coil to generate a critical current.

[0012] Step 2: Due to the high B of the HTS tape, a normal state region cannot be generated in the stator short tape. Instead, as the permanent magnet flywheel rotates, it is affected by a traveling magnetic field wave with an amplitude between B C2 and B C1 and B C2 . The magnetic flux passing through it experiences a cyclic process of increasing and then decreasing, generating a net DC voltage V dc and a dynamic resistance R d , thereby generating an increment of DC induced current in each cycle until the current I L in the closed-loop circuit formed by the superconducting component reaches a saturation value I C close to the critical current I L0 ;

[0013] Step 3: Set L as the inductance of the superconducting coil and R as the resistance of the closed-loop circuit formed by the superconducting component. This resistance includes the resistance R J of the HTS joints in the circuit and the dynamic resistance R of the HTS tape wound around the superconducting coil.d ’, then the current I in the circuit L and the magnetic induction intensity B in the superconducting coil follow the following exponential decay law:

[0014] I L (t) = I L (0)·exp[(-R / L)·t], B(t) = B(0)·exp[(-R / L)·t] (1)

[0015] where t represents time / s. When the above formula is applied to the superconducting component and the permanent magnet component, the closed-loop circuits of superconducting components with different powers have different decay characteristics. The permanent magnet component pumps a current and a magnetic flux increment into the circuit in real time to make up for this decay and maintain the magnetic induction intensity B in the superconducting coil unchanged. The energy consumption required for this magnetic flux increment, that is, the excitation energy, is marked as "ΔE B ", and we get:

[0016] ΔE B = 1 / 2·[(I L0 ) 2 -(I L0 -ΔI L ) 2 ·L = (I L0 *ΔI L -ΔI L 2 / 2)·L (2)

[0017] When the HTS joint resistance is small and the magnetic induction intensity decays very slowly, ΔI L << I L0 , then:

[0018] ΔE B = 2·(ΔI L / I L0 )·E B0 (3)

[0019] When this excitation energy is in the unit of W, it is expressed as:

[0020] ΔE B = 2·(ΔI L / I L0 )·E B0 ·f (4)

[0021] The joule heats (Q J and Q d ') caused by the HTS joint resistance R J and the dynamic resistance R d ' of the HTS tape used to wind the superconducting coil are the other two energy consumptions in the closed-loop circuit, that is:

[0022] Q J = I L0 2 ·R J (5)

[0023] Q d ′ = I L0 2 ·R d ′ (6)

[0024] R d ′ is calculated using the exponential law:

[0025] R d ′ = V0·[I L0 / I C (B r )] n / I L0 (7)

[0026] where V0 = 1 μV / cm, and I C (B r ) is the critical current of the HTS tape under the action of the magnetic field, which is directly affected by the vertical component B r of B r ⊥ and is expressed by the following equation:

[0027] I C (B r ) = I c (0) / (1 + |B r ⊥ | / B0) (8)

[0028] The sum of the above three energy consumptions is equal to the energy output from the permanent magnet assembly in the closed-loop circuit, which is labeled as "P FP " and is expressed as follows:

[0029] P FP = ΔE B + Q J + Q d ′ (9);

[0030] Step 4: When the permanent magnet assembly is working, the stator short tape is affected by the traveling magnetic field wave, generating flux motion and dynamic resistance R d in it, which is the basis for generating the net DC voltage V dc in the closed-loop circuit. Due to the existence of the alternating magnetic field, the dynamic resistance R d and the flux motion generate energy consumption in the stator short tape, including the AC dynamic resistance loss Q d and the hysteresis loss Q B, the energy consumption of these two parts is the intrinsic energy consumption, and its total value is marked as "Q FP ", that is:

[0031] Q FP =Q d +Q B (10)

[0032] Therefore, the total electric energy obtained by the superconducting component through the rotation of the permanent magnet flywheel's mechanical energy is E M , and it is distributed into two parts in the closed-loop circuit formed by the superconducting component: the intrinsic energy consumption "Q FP " and the net output energy "P FP ", that is:

[0033] E M =P FP +Q FP =ΔE B +Q J +Q d '+Q FP (11);

[0034] Step Five: According to the actually measured traveling magnetic field wave waveform, the net DC voltage V dc on the stator short band, the saturated excitation current I L0 , the resistance R J of the HTS joint, and the total electric energy E M obtained by the rotation of the permanent magnet flywheel's mechanical energy, and the excitation energy ΔE B required to maintain the magnetic induction intensity of the superconducting component unchanged, and then obtain the value of the intrinsic energy consumption according to the following formula:

[0035] Q FP =E M -ΔE B -Q J -Q d ' (12).

[0036] A further improvement lies in that: in the second step, the traveling magnetic field wave is an alternating magnetic field with a DC bias.

[0037] A further improvement lies in that: in the second step, the faster the permanent magnet flywheel rotates, that is, the higher the frequency of the traveling magnetic field wave, the faster I L rises, and the closer I L0 is to I c .

[0038] The beneficial effects of the present invention are as follows: The present invention utilizes the cooperation of a permanent magnet component and a superconducting component. The rotation of the permanent magnet flywheel generates a traveling magnetic field wave, which acts on the stator short tape, generating a direct current in a closed-loop circuit to perform brushless excitation on the superconducting coil. In the experimental method, by measuring the mechanical-electromagnetic conversion energy and subtracting the excitation energy, the joint resistance energy consumption, and the dynamic resistance energy consumption of the HTS tape, the value of the intrinsic energy consumption is obtained. Combining with the corresponding theoretical calculation method to calculate the objectively existing physical quantity of the intrinsic energy consumption, analyzing and determining the internal physical mechanism of the intrinsic energy consumption, it is determined that the action of the traveling magnetic field wave is the fundamental reason for the generation of the intrinsic energy consumption in the stator short tape, which has very high practical value for the research of HTS flux pump technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 is the front view of the present invention;

[0040] Figure 2 is the schematic structural diagram of the device of the present invention;

[0041] Figure 3 is the equivalent circuit diagram of the present invention;

[0042] Figure 4 is the schematic diagram showing the change of the energy consumption value of the present invention with frequency;

[0043] Figure 5 is the schematic diagram of the quantitative relationship of the physical quantities of the present invention.

[0044] Among them: 1. Cooling box; 2. Rotating shaft; 3. Permanent magnet flywheel; 4. Superconducting coil; 5. HTS joint; 6. Stator short tape; 7. Bracket. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045] In order to deepen the understanding of the present invention, the following will further elaborate on the present invention in combination with embodiments. These embodiments are only used to explain the present invention and do not constitute a limitation to the protection scope of the present invention.

[0046] According to Figure 1 、 2 、and as shown in FIG. 3, this embodiment provides a test device for the intrinsic energy consumption of a high-temperature superconducting flux pump, including a cooling box 1, a superconducting component, and a permanent magnet component. The superconducting component is located inside the cooling box 1. The permanent magnet component includes a rotating shaft 2 and a permanent magnet flywheel 3. The permanent magnet flywheel 3 is provided on the rotating shaft 2. The superconducting component includes a superconducting coil 4, an HTS joint 5, and a stator short tape 6. The superconducting coil 4 is arranged inside the cooling box 1 and is wound by HTS tape. The two ends of the superconducting coil 4 are HTS joints 5, and stator short tapes 6 are connected to the two ends of the HTS joints 5. The permanent magnet flywheel 3 is adjacent to the stator short tape 6.

[0047] The interior of the cooling box 1 is filled with liquid nitrogen refrigerant.

[0048] A bracket 7 is provided on the superconducting coil 4, and the bracket 7 is fixed to the bottom inside the cooling box 1.

[0049] There is a gap between the superconducting component and the permanent magnet component and they do not contact each other.

[0050] The superconducting coil 4, the HTS joint 5 and the stator short strap 6 form a closed-loop energized circuit.

[0051] According to Figure 1 , 2 , Figures 3, 4, and 5 show that this embodiment provides a test method for the intrinsic energy consumption of a high-temperature superconducting flux pump, including the following steps:

[0052] Step 1: Place the superconducting component and the permanent magnet component in the low-temperature environment of the liquid nitrogen refrigerant, rotate the rotating shaft 2 to drive the permanent magnet flywheel 3 to rotate, generate a traveling magnetic field wave, and the traveling magnetic field wave performs brushless excitation on the superconducting coil 4 to generate a critical current;

[0053] Step 2: Due to the high B C2 of the HTS tape, a normal state region cannot be generated in the stator short strap 6. Instead, as the permanent magnet flywheel 3 rotates, it is affected by a traveling magnetic field wave with an amplitude between B C1 and B C2 . The traveling magnetic field wave is an alternating magnetic field with a DC bias. The magnetic flux passing through the stator short strap 6 undergoes a cyclic process of increasing and then decreasing, generating a DC voltage net value V dc and a dynamic resistance R d . Thus, a DC induced current increment is generated in each cycle until the current I L in the closed-loop circuit formed by the superconducting components reaches a saturation value I C close to the critical current I L0 . The faster the permanent magnet flywheel 3 rotates, that is, the higher the frequency of the traveling magnetic field wave, the faster I L rises, and the closer I L0 is to I c ;

[0054] Step 3: Set L as the inductance of the superconducting coil 4 and R as the resistance of the closed-loop circuit formed by the superconducting components. This resistance includes the resistance R J of the HTS joint 5 in the circuit and the dynamic resistance R d ' of the HTS tape wound around the superconducting coil 4. Then, the current I L in the circuit and the magnetic induction intensity B in the superconducting coil 4 follow the following exponential decay law:

[0055] I L (t) = IL (0)·exp[(-R / L)·t], B(t) = B(0)·exp[(-R / L)·t] (1)

[0056] Where t represents time / s. When the above formula is applied to the superconducting component and the permanent magnet component, the closed-loop circuits of superconducting components with different powers have different attenuation characteristics. The permanent magnet component pumps a current and magnetic flux increment into the circuit in real time to compensate for this attenuation and maintain the magnetic induction intensity B in the superconducting coil 4 unchanged. The energy consumption required for this magnetic flux increment, i.e., the excitation energy, is marked as "ΔE" B ", and we get:

[0057] ΔE B = 1 / 2·[(I L0 ) 2 -(I L0 -ΔI L ) 2 ·L = (I L0 *ΔI L -ΔI L 2 / 2)·L (2)

[0058] When the resistance of the HTS joint 5 is small and the attenuation of the magnetic induction intensity is very slow, ΔI L << I L0 , then:

[0059] ΔE B = 2·(ΔI L / I L0 )·E B0 (3)

[0060] When this excitation energy is in the unit of W, it is expressed as:

[0061] ΔE B = 2·(ΔI L / I L0 )·E B0 ·f (4)

[0062] The joule heats (Q J and Q d ') respectively caused by the resistance R J of the HTS joint 5 and the dynamic resistance R d ' of the HTS tape used to wind the superconducting coil 4 are the other two energy consumptions in the closed-loop circuit, that is:

[0063] Q J = I L0 2 ·R J (5)

[0064] Q dI' = I L0 2 ·R d ' (6)

[0065] R d The calculation of R' uses the exponential law:

[0066] R d ' = V0·[I L0 / I C (B r )] n / I L0 (7)

[0067] where V0 = 1 μV / cm, and I C (B r ) is the critical current of the HTS tape under the action of the magnetic field, which is more directly affected by the vertical component B r of B r ⊥ and is expressed by the following equation:

[0068] I C (B r ) = I c (0) / (1 + |B r ⊥ | / B0) (8)

[0069] The sum of the above three energy consumptions is equal to the energy output from the permanent magnet assembly in the closed-loop circuit, which is labeled as "P FP " and is expressed as follows:

[0070] P FP = ΔE B + Q J + Q d ' (9);

[0071] Step 4: When the permanent magnet assembly is working, the stator short tape 6 is affected by the traveling magnetic field wave, generating flux movement and dynamic resistance R d in it, which is the basis for generating the net DC voltage V dc in the closed-loop circuit. Due to the existence of the alternating magnetic field, the dynamic resistance R d and flux movement generate energy consumption in the stator short tape 6, including the AC dynamic resistance loss Q d and the hysteresis loss Q B . These two parts of energy consumption are the intrinsic energy consumption, and their total value is labeled as "Q FP ", that is:

[0072] Q FP = Q d + Q B (10)

[0073] Therefore, the total electric energy obtained by the superconducting component through the rotation of the mechanical energy of the permanent magnet flywheel 3 is E M , and it is distributed into two parts in the closed-loop circuit formed by the superconducting component: the intrinsic energy consumption "Q FP " and the net output energy "P FP ", that is:

[0074] E M = P FP + Q FP = ΔE B + Q J + Q d '+ Q FP (11);

[0075] Step Five: According to the actually measured traveling magnetic field wave waveform, the net DC voltage V dc on the stator short strap 6, the saturated excitation current I L0 , the resistance R J of the HTS joint 5, and the total electric energy E M obtained by the rotation of the mechanical energy of the permanent magnet flywheel 3, and the excitation energy ΔE B required to maintain the magnetic induction intensity of the superconducting component unchanged, and then obtain the value of the intrinsic energy consumption according to the following formula:

[0076] Q FP = E M - ΔE B - Q J - Q d ' (12).

[0077] Verification Example:

[0078] A superconducting component and a permanent magnet component form a flux pump. Taking the literature [Ma J, et al., Rotating Permanent MagnetsBased Flux Pump for HTS No-Insulation Coil, EEE Trans.Appl.Supercond.2019, 29(5): 5202106] as an example, researchers obtained and maintained different saturated excitation currents I L0 at the traveling magnetic field wave frequencies of 10 - 160 Hz, that is, at a certain frequency, the net output energy "P FP " of the flux pump, the excitation energy ΔE B at this time, the HTS joint resistance energy consumption Q J of the superconducting tape, and the dynamic resistance energy consumption Q d ' of the superconducting tape maintain a dynamic balance state when added together. According to the data of the insulated coil (INS Coil) in "Table I" in the literature (including R J= 205.5 nΩ, the calculated length of the superconducting tape is 14 meters), and the equations (2), (5), (6), (7), (8) in this article. Assuming that the n value of the I-V curve of the superconducting coil with an inductance of 123 μH used in the experiment is set to 18, the relevant parameters at different frequencies can be calculated, as listed in Table 1:

[0079] Table 1 Calculation results of relevant parameters in the literature

[0080]

[0081] R in Table 1 d ’ is the dynamic resistance of the superconducting tape when the flux pump is in a non-operating state, obtained by calculating with formula (7) (where I C (B r ) = 62 A); the loop resistance value R that causes the loop current to decay is R = R d ’ + R J . It should be noted that the value of R d ’ calculated here according to the basic exponential law of the I-V curve is several times the value of R d reported in this literature because they respectively reflect the characteristics during the saturated excitation current and "charging". V d is the voltage drop across the superconducting coil when maintaining the saturated excitation current at a certain frequency (including the two joints connected to the stator of the superconducting short tape of the flux pump); listing the value of this physical quantity in the unit of μV / cm can directly show that when I L is lower than I c , V d is still less than Vc (1 μV / cm). The variation of each energy consumption value with frequency is as shown in Figure 4 , the excitation energy ΔE B , the energy consumption Q J of the superconducting tape joint resistance, the energy consumption Q d ’ of the superconducting tape dynamic resistance, and the net output energy P FP of the flux pump, calculated from the experimental data in the literature [Ma J, et al., Rotating Permanent Magnets Based Flux Pump for HTS No-Insulation Coil, EEE Trans. Appl. Supercond. 2019, 29(5): 5202106]. It can be seen from Figure 4 that the higher the frequency, the closer the loop current I L is to the critical current I c of the superconducting coil, the higher the proportion of the excitation energy ΔE B . At 10 Hz and 20 Hz, ΔE Bare only 2.3 mW and 7.8 mW respectively, which are close to the value of Q d '; however, when the frequency rises to 120 Hz and 160 Hz, they reach 142 mW and 209 mW respectively, far exceeding Q d ' at the same frequency; meanwhile, the net output energy of the flux pump increases from 4.5 mW and 15 mW to 164 mW and 233 mW. This shows that due to the increase in the dynamic resistance R d ' of the superconducting tape and the small inductance of the superconducting coil, the decay rate of the loop current is significantly accelerated, resulting in the excitation energy ΔE L required to maintain I B constant dominating the demand for its static output energy P FP in this flux pump device. As the frequency rises from 10 Hz to 160 Hz, the energy consumption Q J of the superconducting tape joint resistance only increases from 0.5 mW to 0.7 mW, accounting for a very small proportion in the total energy consumption, especially at higher frequencies.

[0082] The sum of the static output energy P FP of the flux pump and its intrinsic energy consumption Q FP is the mechanical-electromagnetic conversion energy E M of the flux pump. This E M can be measured experimentally. Given that there is no available experimental data for reference, in this paper, it is assumed that the energy obtained by the flux pump through "mechanical-electromagnetic" conversion in each cycle is a constant. This energy constant is an important parameter of the flux pump, labeled as "e m ". By giving an appropriate value to e m , a preliminary analysis of the dynamic balance relationship of "E M = P FP + Q FP " can be attempted. According to this assumption, E M in equation (11) is proportional to the frequency and satisfies the basic condition of "E M > P FP " at any frequency. Therefore, e m must not be less than about 1.5 mJ; thus, we take e m = 1.9 mJ. At this time, the quantitative relationship of the three physical quantities is as Figure 5 shown. In the literature [Ma J, et al., Rotating Permanent Magnets Based Flux Pump for HTS No-Insulation Coil, EEE Trans. Appl. Supercond. 2019, 29(5): 5202106], the mechanical-electromagnetic conversion energy E M and the net output energy P FPand the intrinsic energy consumption Q FP The relationship; Assuming E M = 1.9 mJ·f and 3.7 mJ·f respectively for comparison; When the frequency is low, the proportion of the intrinsic energy consumption of the flux pump is relatively large, and it may even exceed its net output energy; When the frequency increases, the growth of the intrinsic internal energy consumption Q FP is slower than that of P FP , so the proportion becomes smaller and is significantly lower than the proportion of P FP . Of course, e m may have a higher value. When e m = 3.7 mJ, the growth rate of Q FP with frequency is equivalent to that of P FP , but still shows a linear growth trend; That is, operating the flux pump at high frequencies will not cause a sharp increase in the intrinsic energy consumption of the flux pump.

[0083] The present invention utilizes the cooperation of a permanent magnet component and a superconducting component. The permanent magnet flywheel 3 rotates to generate a traveling magnetic field wave, which acts on the stator short tape 6 to generate a direct current in a closed loop and excite the superconducting coil 4 brushlessly. In the experimental method, by measuring the mechanical-electromagnetic conversion energy and subtracting the excitation energy, the joint resistance energy consumption, and the dynamic resistance energy consumption of the HTS tape, the value of the intrinsic energy consumption is obtained. Combining with the corresponding theoretical calculation method to calculate the objectively existing physical quantity of the intrinsic energy consumption, analyzing and determining the internal physical mechanism of the intrinsic energy consumption, it is determined that the action of the traveling magnetic field wave is the fundamental reason for generating the intrinsic energy consumption in the stator short tape, which has very high practical value for the research of HTS flux pump technology.

[0084] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of the present invention claimed is defined by the appended claims and their equivalents.

Claims

1. A test method for the intrinsic energy consumption of a high-temperature superconducting flux pump, providing the following device, including a cooling box (1), a superconducting component, and a permanent magnet component, characterized in that: The superconducting component is located inside the cooling box (1). The permanent magnet component includes a rotating shaft (2) and a permanent magnet flywheel (3). The permanent magnet flywheel (3) is provided on the rotating shaft (2). The superconducting component includes a superconducting coil (4), an HTS joint (5), and a stator short strap (6). The superconducting coil (4) is arranged inside the cooling box (1), and the superconducting coil (4) is wound by HTS tapes. The two ends of the superconducting coil (4) are HTS joints (5), and stator short straps (6) are connected at the two ends of the HTS joints (5). The permanent magnet flywheel (3) is adjacent to the stator short strap (6); Liquid nitrogen refrigerant is filled inside the cooling box (1); A bracket (7) is provided on the superconducting coil (4), and the bracket (7) is fixed to the bottom inside the cooling box (1); There is a gap between the superconducting component and the permanent magnet component and they do not contact each other; The superconducting coil (4), the HTS joint (5), and the stator short strap (6) form a closed-loop energized circuit; The method includes the following steps: Step 1: Place the superconducting component and the permanent magnet component in a low-temperature environment of liquid nitrogen refrigerant, rotate the rotating shaft (2) to drive the permanent magnet flywheel (3) to rotate, generate a traveling magnetic field wave, and the traveling magnetic field wave performs brushless excitation on the superconducting coil (4) to generate a critical current; Step 2: Since the B of the HTS tape is C2 high, a normal state region cannot be generated in the stator short tape (6). Instead, as the permanent magnet flywheel (3) rotates, it is subjected to a traveling magnetic field wave with an amplitude between B C1 and B C2 . The magnetic flux passing through it undergoes a cyclic process of increasing and then decreasing, generating a net DC voltage V dc and a dynamic resistance R d . As a result, a DC induced current increment is generated in each cycle until the current I L in the closed-loop circuit composed of superconducting components reaches a saturation value I C close to the critical current I L0 ; Step 3: Set L as the inductance of the superconducting coil (4), and R as the resistance of the closed-loop circuit formed by the superconducting components. This resistance includes the resistance R J of the HTS joints (5) in the loop and the dynamic resistance R d ’ of the HTS tape used to wind the superconducting coil (4). Then, the current I L in the loop and the magnetic induction intensity B in the superconducting coil (4) follow the following exponential decay law: I L i(t) = I L i(0)·exp[(-R / L)·t], B(t) = B(0)·exp[(-R / L)·t] (1) Where t represents time / s. When the above formula is applied to the superconducting component and the permanent magnet component, the closed-loop circuits of superconducting components with different powers have different attenuation characteristics. The permanent magnet component pumps a current and a magnetic flux increment into the circuit in real time to compensate for this attenuation and maintain the magnetic induction intensity B in the superconducting coil (4) unchanged. The energy consumption required for this magnetic flux increment, that is, the excitation energy, is marked as "ΔE" B ”, and we get: ΔE B = 1 / 2·[(I L0 ) 2 -(I L0 -ΔI L ) 2 ·L = (I L0 *ΔI L -ΔI L 2 / 2)·L (2) When the resistance of the HTS joint (5) is small and the attenuation of the magnetic induction intensity is very slow, ΔI L <<I L0 , then: ΔE B = 2·(ΔI L / I L0 )·E B0 (3) When this excitation energy is in units of W, it is expressed as: ΔE B = 2·(ΔI L / I L0 )·E B0 ·f(4) HTS joint (5) resistance R J and the dynamic resistance R of the HTS tape used to wind the superconducting coil (4) d ’ respectively result in the Joule heat (Q J and Q d ’), which are the other two energy consumptions in the closed-loop circuit, namely: Q J = I L0 2 · R J (5) Q d ’ = I L0 2 · R d ’ (6) R d 'Calculate using the exponential law: R d ’ = V0·[I L0 / I C (B r )] n / I L0 (7) where V0 = 1 μV / cm, and I C (B r ) is the critical current of the HTS tape under the action of the magnetic field, which is directly affected by the vertical component B r of B r ⊥ and is expressed by the following equation: I C (B r ) = I c (0) / (1 + |B r ⊥ | / B0) (8) The sum of the above three energy consumptions is correspondingly equal to the energy output from the permanent magnet assembly in this closed-loop circuit, which is labeled as "P" FP ", expressed as follows: P FP = ΔE B + Q J + Q d ’ (9); Step Four: When the permanent magnet assembly is working, the stator short belt (6) is affected by the traveling magnetic field wave, generating magnetic flux movement and dynamic resistance R therein d , which is the basis for generating the net DC voltage V dc in the closed-loop circuit. Due to the existence of the alternating magnetic field, the dynamic resistance R d and the magnetic flux movement generate energy consumption in the stator short belt (6), including the AC dynamic resistance loss Q d and the hysteresis loss Q B . These two parts of energy consumption are the intrinsic energy consumption, and their total value is labeled as "Q FP ", that is: Q FP = Q d + Q B (10) Therefore, the total electric energy obtained by the superconducting component through the rotation of the mechanical energy of the permanent magnet flywheel (3) is E M , which is distributed into two parts in the closed-loop circuit formed by the superconducting component: the intrinsic energy consumption "Q FP " and the net output energy "P FP ", that is: E M = P FP + Q FP = ΔE B + Q J + Q d ’ + Q FP (11); Step Five: According to the actually measured traveling magnetic field wave waveform, the net DC voltage V on the stator short strap (6), dc the saturation excitation current I, L0 the resistance R of the HTS joint (5), J and the total electric energy E obtained from the rotational mechanical energy of the permanent magnet flywheel (3), M the excitation energy ΔE required to maintain the magnetic induction intensity of the superconducting component unchanged, B wherein, E M is obtained by subtracting the motor energy consumption when the permanent magnet component is not working from the total motor energy consumption when the permanent magnet component is working, and then the value of the energy consumption of this certificate is obtained according to the following formula: Q FP = E M - ΔE B - Q J - Q d ’ (12).

2. The test method for the intrinsic energy consumption of a high-temperature superconducting flux pump according to claim 1, wherein: In the second step, the traveling magnetic field wave is an alternating magnetic field with a DC bias.

3. A test method for the intrinsic energy consumption of a high-temperature superconducting flux pump according to claim 2, characterized in that: In the second step, the faster the permanent magnet flywheel (3) rotates, that is, the higher the frequency of the traveling magnetic field wave, the faster I L rises, and the faster I L0 gets closer to I c .

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