A method and equipment for calculating AC loss of a three-phase overlay superconducting cable

Abstract

This invention relates to a method and apparatus for calculating the AC loss of a three-phase integrated superconducting cable. The method includes the following steps: calculating the AC loss of the main body portion, which includes AC losses of multiple harmonic components obtained analytically; calculating the AC loss of the terminal portion, which includes Joule heat loss and leakage heat loss; and adding the AC losses of the main body portion and the AC losses of the terminal portion to obtain the AC loss of the three-phase integrated superconducting cable. The multiple harmonic components include hysteresis losses generated by main current fluctuations and hysteresis losses generated by multiple small current fluctuations. The main current fluctuation is a sine wave with the fundamental frequency of the load current as its amplitude, and the small current fluctuations are current fluctuations caused by harmonic current distortion. The harmonic currents are obtained using an interlayer current distribution solution method. Compared with existing technologies, this invention can improve the accuracy of the calculation results.

Description

Technical Field

[0001] This invention belongs to the field of power transmission and distribution technology, and in particular relates to a method and equipment for calculating AC loss of a three-phase integrated superconducting cable. Background Technology

[0002] Three-phase superconducting cables possess advantages such as large transmission capacity, low loss, and environmental friendliness, making them one of the power equipment sectors currently receiving significant research and development both domestically and internationally. Their structure consists of three mutually insulated superconducting cores encased in a vacuum-insulated tube. Each superconducting core comprises, from the inside out, a copper backing, a superconducting conductor layer, and an insulation layer. When alternating current is transmitted through a superconducting cable or when it is exposed to an alternating magnetic field, the changing magnetic field induces an electric field in the superconductor, resulting in energy loss, known as alternating current loss. AC loss is one of the fundamental parameters that must be considered in the design and operation of superconducting cable systems. Its calculation methods mainly include analytical calculation methods and numerical calculation methods. Currently, finite element software based on numerical calculation is mostly used to simulate and solve the AC loss of superconducting cables. This can provide a relatively intuitive understanding of the current distribution and the changes and distribution of AC loss. However, due to the complex spiral structure and precise material arrangement of superconducting cables, the computational complexity of the entire calculation model is high. If it also contains multiple harmonic current components of different amplitudes and phases, it will be even more time-consuming and labor-intensive. Moreover, since the AC loss of superconducting cables is on the order of magnitude small, the mesh, which is the key to ensuring the accuracy of the calculation, must be finely divided to obtain a relatively ideal calculation result, but this also greatly increases the simulation running time.

[0003] Chinese invention patent CN117871987B discloses a method for detecting losses in long-distance superconducting cables, combining electrical and thermal measurement methods to detect various losses in long-distance superconducting cables without power interruption. However, when load equipment is connected to the power system, it draws electrical energy from the grid to form a load current. Due to the presence of various nonlinear and asymmetrical loads, such as power electronic equipment (rectifiers, frequency converters), electric arc furnaces, and electromagnets, harmonic components are introduced into the load current, generating additional AC losses in the superconducting cable system and reducing transmission efficiency. Therefore, research on superconducting cable losses should not be limited to the AC losses of the superconducting tape itself under normal load current. A separate AC loss calculation method needs to be designed to consider the impact of nonlinear load currents on the AC losses of three-phase integrated superconducting cable systems. This is of great significance for optimizing the design of superconducting cables and guiding their operation and maintenance. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the existing technology by providing a method and equipment for calculating the AC loss of a three-phase integrated superconducting cable, thereby improving the accuracy and comprehensiveness of the calculation results.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] This invention provides a method for calculating the AC loss of a three-phase overlay superconducting cable, comprising the following steps:

[0007] Calculate the AC loss of the main body section, which includes the AC loss of the multi-order harmonic components solved by analytical methods; calculate the AC loss of the terminal section, which includes Joule heat loss and leakage heat loss; add the AC loss of the main body section and the AC loss of the terminal section to obtain the AC loss of the three-phase integrated superconducting cable.

[0008] The AC losses of the multi-order harmonic components include hysteresis losses generated by the main current fluctuations and hysteresis losses generated by multiple small current fluctuations. The main current fluctuations are sine waves with the fundamental frequency of the load current as the amplitude, and the small current fluctuations are current fluctuations formed by the distortion of harmonic currents. The harmonic currents are obtained by the interlayer current distribution solution method.

[0009] Furthermore, the specific formula for calculating the AC loss of the multi-order harmonic components is as follows:

[0010]

[0011] Where Q represents the AC loss of the multi-order harmonic components, Q major Hysteresis loss caused by main current fluctuations. To represent the hysteresis loss caused by the i-th small current fluctuation. The self-field transmission hysteresis loss is caused by the main current fluctuation. Q is the self-field transmission hysteresis loss caused by small current fluctuations. mag External field transmission hysteresis loss caused by current, including external field transmission hysteresis loss caused by main current fluctuations. External field transmission hysteresis loss caused by small current fluctuations

[0012] Furthermore, the self-field transmission hysteresis loss generated by the main current fluctuation The specific calculation formula is as follows:

[0013]

[0014] i i =I major / I c

[0015] Where f is the operating frequency, N j Let be the number of superconducting tape elements in the j-th layer, μ0 be the vacuum permeability, and i i Main current relative index, I majorMain current fluctuation amplitude, I c denoted as the critical current density of the superconducting cable, and n as the total number of superconducting layers.

[0016] Furthermore, the self-field transmission hysteresis loss generated by small current fluctuations The specific calculation formula is as follows:

[0017]

[0018] i i =I minor / I c

[0019] in, Let be the number of the i-th type of small current fluctuation. For the self-field transmission hysteresis loss caused by the i-th type of small current fluctuation, i max N represents the number of small current types, f represents the operating frequency, and N represents the number of different types of small currents. j Let I be the number of superconducting tape elements in the i-th layer, μ0 be the free permeability, and n be the total number of superconducting layers. c i is the critical current density of the superconducting cable. i I is a relative indicator for low current. minor This represents the amplitude of small current fluctuations.

[0020] Furthermore, the external field transmission hysteresis loss Q generated by the current mag The specific calculation formula is as follows:

[0021] Q mag =∑Q magi

[0022]

[0023] Among them, Q magi Let f be the external field magnetization loss of the i-th superconducting tape layer, f be the operating frequency, and B be the value of B. i Let β be the magnetic flux density at the i-th layer of the superconducting cable. i S is a relative index of magnetic induction. i Let B be the cross-sectional area of ​​the i-th layer of superconducting tape. zi and B θi J represents the axial magnetic field generated inside the i-th layer by the circumferential current and the circumferential magnetic field generated outside the i-th layer by the axial current of the i-th layer, respectively. C denoted as the critical current of the superconducting tape under the influence of a magnetic field, μ0 is the vacuum permeability, and b is half the thickness of the superconducting cable tape.

[0024] Furthermore, in solving for the axial magnetic field B generated inside the i-th layer by the circumferential current in the i-th layer... zi and the circumferential magnetic field B generated by the axial current of the i-th layer outside the i-th layer. θiAt that time, the main current fluctuation amplitude I major Instead of calculating the current value for each layer, the specific calculation formula is as follows:

[0025]

[0026]

[0027] Where n is the total number of superconducting layers, ε k As a relative dielectric, L pk and L pi To control the pitch, r ic and r io denoted as the inner radius and outer radius of the i-th current-carrying layer, respectively.

[0028] Furthermore, the specific formula for calculating the Joule heat loss is as follows:

[0029] W = n p I 2 R p

[0030] Where W is the Joule heat loss, n p Where I is the number of phases in the superconducting cable, I is the magnitude of the single-phase current, and R is the current in the superconducting cable. p This refers to the single-phase terminating resistor of a superconducting cable.

[0031] Furthermore, the specific formula for calculating the heat leakage loss is as follows:

[0032]

[0033] Among them, W ter Where I is the heat loss due to leakage, K is the thermal conductivity, ρ is the resistivity, and T is the temperature.

[0034] Furthermore, the specific steps of the method for solving the interlayer current distribution are as follows:

[0035] Construct an equivalent circuit diagram of a multilayer superconducting cable, write Kirchhoff voltage equations for each phase and each layer for each order current containing harmonic components, and combine them to obtain the Kirchhoff voltage equation matrix.

[0036] Based on the Kirchhoff voltage equation matrix, the voltage magnitude of each phase is solved by using the current magnitude of each phase and the current relationship between the conductive layer and the shielding layer, and the current distribution of each layer is solved by using the fact that the voltages of each layer in each phase are the same.

[0037] The present invention also provides an electronic device, including a memory, a processor, and a program stored in the memory, wherein the processor executes the program to implement the above-described method.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] 1. This invention proposes a method for calculating the AC loss of a three-phase integrated superconducting cable. The AC loss of the three-phase integrated superconducting cable is decomposed into the main body part and the terminal part, which are solved separately. The AC loss of the terminal part includes Joule heat loss and leakage heat loss. The AC loss of the main body part includes the AC loss of multiple harmonic components solved by analytical methods. Specifically, the AC loss of multiple harmonic components includes the hysteresis loss generated by the main current fluctuation and the hysteresis loss generated by multiple small current fluctuations. The main current fluctuation is a sine wave with the fundamental frequency of the load current as the amplitude. The small current fluctuation is the current fluctuation formed by the distortion of the harmonic current. The harmonic current is obtained by solving the interlayer current distribution method. The above method can achieve fast and accurate calculation.

[0040] 2. This invention solves for the axial magnetic field B generated inside the i-th layer by the circumferential current in the i-th layer. zi and the circumferential magnetic field B generated by the axial current of the i-th layer outside the i-th layer. θi At that time, the main current fluctuation amplitude I major Instead of solving for the current value of each layer, this method simplifies the calculation process, improves calculation efficiency, and facilitates the analysis of the main influencing factors. Attached Figure Description

[0041] Figure 1 This is a flowchart of the method of the present invention;

[0042] Figure 2 The current waveform after the 9th harmonic current component is applied to a sinusoidal alternating current;

[0043] Figure 3 The main and small hysteresis loops containing the 7th harmonic component current;

[0044] Figure 4 The thermal conductivity of copper conductors at different temperatures;

[0045] Figure 5 The resistivity of copper conductors at different temperatures;

[0046] Figure 6 This is a schematic diagram of the calculation results.

[0047] Among them, (6a) represents the numerical values ​​of the three parts: the superconducting cable body loss, the terminal Joule heat loss, and the terminal leakage heat loss, and (6b) represents the total loss obtained by superposition. Detailed Implementation

[0048] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0049] Example 1

[0050] This embodiment provides a method for calculating the AC loss of a three-phase integrated superconducting cable, such as... Figure 1 As shown, it includes the following steps:

[0051] S1. Calculate the AC loss of the main body.

[0052] Typically, harmonic current components are formed by the superposition of harmonic currents of various orders, phases, and amplitudes. When three-phase currents containing harmonic currents enter a multilayer superconducting cable, the harmonic components also need to be shunted according to the cable structure. Therefore, the harmonic currents actually distributed in each layer should also be solved using the interlayer current distribution solution method. The steps are as follows: Construct an equivalent circuit diagram of the multilayer superconducting cable; write Kirchhoff voltage equations for each phase and each layer for each order of current containing harmonic components; combine them to obtain the Kirchhoff voltage equation matrix; based on the Kirchhoff voltage equation matrix, solve for the voltage magnitude of each phase using the current magnitude of each phase and the current relationship between the conductive layer and the shielding layer; solve for the current distribution of each layer using the fact that the voltages of each layer in each phase are the same. The interlayer current distribution solution method has been studied before, and the specific steps will not be repeated in this embodiment.

[0053] The AC losses in the main body include AC losses from multiple harmonic components, which are solved analytically in this embodiment. Hysteresis loss, which accounts for the majority of AC losses, originates from magnetic flux changes caused by magnetic field variations. When harmonic components are present in the system, their distortion effect on the sinusoidal current causes new peaks and troughs of varying degrees, quantities, and positions to appear on the originally regular waveform. This means that the distorted current generates additional magnetic flux changes, and this additional hysteresis loss largely depends not on the instantaneous value of the distorted current, but on the amplitude of each rise and fall of the distorted current. Therefore, analyzing the load current containing harmonic components reveals that, in addition to the main current fluctuations formed by the fundamental wave, several small current fluctuations are also generated due to the distortion of the harmonic components. The current waveform after the 9th harmonic current component is applied to the sinusoidal AC current is shown below. Figure 2 As shown, the original sinusoidal current has only one peak and one trough in one cycle. After adding a harmonic current with a larger amplitude, it becomes 9 peaks and 9 troughs.

[0054] The load current under the superposition of multiple harmonic currents is shown in the following formula:

[0055]

[0056] Among them, THD k This represents the degree of distortion of the fundamental load current by the k-th harmonic current component. max This indicates the highest order of the harmonic current.

[0057] The AC loss of a load current containing 9th harmonic components can be calculated by dividing it into two parts. The sinusoidal wave with the fundamental frequency of the load current as its amplitude is defined as the major current fluctuation, and the amplitude variations formed by the peaks and troughs of the other components are defined as the minor current fluctuation. The AC loss Q of the multi-harmonic current should be the sum of the hysteresis losses generated by the major current fluctuation and the minor current fluctuation. The specific calculation formula is as follows:

[0058]

[0059] Among them, Q major Hysteresis loss caused by main current fluctuations. To represent the hysteresis loss caused by the i-th small current fluctuation. The self-field transmission hysteresis loss is caused by the main current fluctuation. Q is the self-field transmission hysteresis loss caused by small current fluctuations. mag External field transmission hysteresis loss caused by current, including external field transmission hysteresis loss caused by main current fluctuations. External field transmission hysteresis loss caused by small current fluctuations

[0060] Self-field transmission hysteresis loss caused by main current fluctuation The specific calculation formula is as follows:

[0061]

[0062] i i =I major / I c

[0063] Where f is the operating frequency, N j Let be the number of superconducting tape elements in the j-th layer, μ0 be the vacuum permeability, and i i Main current relative index, I major Main current fluctuation amplitude, I c denoted as the critical current density of the superconducting cable, and n as the total number of superconducting layers.

[0064] Self-field transmission hysteresis loss caused by small current fluctuations The specific calculation formula is as follows:

[0065]

[0066] i i =I minor / I c

[0067] in, Let i be the number of small current fluctuations of the i-th type, such as Figure 3 As shown, since the phase of the harmonic components is zero, small current fluctuations all appear symmetrically. For the self-field transmission hysteresis loss caused by the i-th type of small current fluctuation, i max N represents the number of small current types, f represents the operating frequency, and N represents the number of different types of small currents. j Let μj be the number of superconducting tape elements in the j-th layer, μ0 be the free permeability, and n be the total number of superconducting layers. c i is the critical current density of the superconducting cable. i I is a relative indicator for low current. minor This represents the amplitude of small current fluctuations.

[0068] External field transmission hysteresis loss Q generated by current mag The specific calculation formula is as follows:

[0069] Q mag =ΣQ magi

[0070]

[0071] Among them, Q magi Let B be the external field magnetization loss of the i-th superconducting tape layer. i Let β be the magnetic flux density at the i-th layer of the superconducting cable. i S is a relative index of magnetic induction. i Let B be the cross-sectional area of ​​the i-th layer of superconducting tape. zi and B θi J represents the axial magnetic field generated inside the i-th layer by the circumferential current and the circumferential magnetic field generated outside the i-th layer by the axial current of the i-th layer, respectively. C denoted as ρ, where ρ is the critical current of the superconducting tape under the influence of a magnetic field, and b is half the thickness of the superconducting cable tape.

[0072] Solving for the axial magnetic field B generated inside the i-th layer by the circumferential current in the i-th layer. zi and the circumferential magnetic field B generated by the axial current of the i-th layer outside the i-th layer. θi At that time, the main current fluctuation amplitude I major Instead of calculating the current value for each layer, the specific calculation formula is as follows:

[0073]

[0074]

[0075] Where, ε k As a relative dielectric, L pk and L pi To control the pitch, r ic and r io denoted as the inner radius and outer radius of the i-th current-carrying layer, respectively.

[0076] Taking a load current containing a 9th harmonic component with THD = 0.1 and phase 0 as an example, calculate the AC loss of phase A of a three-phase integrated superconducting cable. The expression for this load current is shown in the following formula:

[0077] I A (t)=2200sin(ωt)+220sin(9ωt)

[0078] The load current distribution in this multilayer superconducting cable is as follows:

[0079] I A1 =984.11sin(ωt)+98.411sin(9ωt)

[0080] I A2 =1215.9sin(ωt)+121.589sin(9ωt)

[0081] I S1 =-1078.2sin(ωt)-107.8202sin(9ωt)

[0082] I S2 =-1121.8sin(ωt)-112.1798sin(9ωt)

[0083] Based on this, the AC loss of the multi-order harmonic components is calculated as follows:

[0084]

[0085] Because the three phases in a three-phase integrated structure are independent and have their own independent shielding layers, the shielding layers carry currents that are equal in magnitude and opposite in direction to the internal conductive layers. Therefore, when the three-phase imbalance is caused by a phase change in one phase, the resulting change will not affect the AC losses of the other phases. Furthermore, for the unbalanced phase, a change in current phase will not increase AC losses. Therefore, phase imbalance in a three-phase integrated structure does not affect AC losses.

[0086] S2, calculate the AC loss of the terminal section.

[0087] The AC losses in the terminal section include Joule heat loss W and leakage heat loss W. ter The calculation formulas are as follows:

[0088] W = n p I 2 R p

[0089]

[0090] Where, n pR represents the number of phases in a superconducting cable. p For the single-phase terminating resistance of the superconducting cable, R is taken in this embodiment. p =70μΩ, which is the heat loss, I is the magnitude of the single-phase current, K is the thermal conductivity, ρ is the resistivity, and T is the temperature.

[0091] The thermal conductivity K of copper conductors at different temperatures and the fitted function curves are shown below. Figure 4 As shown, the fitting function is as follows:

[0092]

[0093] The values ​​of thermal conductivity K and resistivity ρ of copper conductors at different temperatures, along with their fitted function curves, are shown below. Figure 5 As shown, the resistivity fitting function is as follows:

[0094] ρ=-7.215×10 -16 T 3 +3.586×10 -13 T 2 +1.282×10 -11 T+2.64×10 -10

[0095] S3. Add the AC loss of the main body part to the AC loss of the terminal part to obtain the AC loss of the three-phase integrated superconducting cable.

[0096] Different currents with varying amplitudes (in 100A increments) are passed through a three-phase overlay superconducting cable. The values ​​of the cable's inherent loss, terminal Joule heat loss, and terminal leakage heat loss are calculated. Figure 6 As shown in (6a), the total loss obtained by superposition is as follows Figure 6 As shown in (6b). Figure 6 It can be seen that the terminal heat leakage loss is a function directly proportional to the current, while the terminal Joule heat loss is a quadratic function. When the transmission current is less than 800A, the current in each strip is small, resulting in low body loss. Ultimately, when the total current reaches the rated current of 2200A, the terminal Joule heat loss accounts for nearly 50% of the total loss.

[0097] Example 2

[0098] This embodiment provides an electronic device, including a memory and a processor. The processor executes a program stored in the memory, the program including several instructions that can perform all or part of the steps of the method described in Embodiment 1. The memory includes a computer-readable storage medium, specifically a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, or any other medium capable of storing program code.

[0099] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A method for calculating the AC loss of a three-phase overlay superconducting cable, characterized in that, Includes the following steps: Calculate the AC loss of the body part, which includes the AC loss of the multi-order harmonic components obtained by analytical methods. Calculate the AC loss of the terminal section, which includes Joule heat loss and leakage heat loss; add the AC loss of the main body section to the AC loss of the terminal section to obtain the AC loss of the three-phase integrated superconducting cable. The AC losses of the multi-order harmonic components include hysteresis losses generated by the main current fluctuations and hysteresis losses generated by multiple small current fluctuations. The main current fluctuations are sine waves with the fundamental frequency of the load current as the amplitude, and the small current fluctuations are current fluctuations formed by the distortion of harmonic currents. The harmonic currents are obtained by the interlayer current distribution solution method.

2. The method for calculating AC loss of a three-phase integrated superconducting cable according to claim 1, characterized in that, The specific formula for calculating the AC loss of the multi-order harmonic components is as follows: Where Q represents the AC loss of the multi-order harmonic components, Q major Hysteresis loss caused by main current fluctuations. To represent the hysteresis loss caused by the i-th small current fluctuation. The self-field transmission hysteresis loss is caused by the main current fluctuation. Q is the self-field transmission hysteresis loss caused by small current fluctuations. mag External field transmission hysteresis loss caused by current, including external field transmission hysteresis loss caused by main current fluctuations. External field transmission hysteresis loss caused by small current fluctuations 3. The method for calculating AC loss of a three-phase integrated superconducting cable according to claim 2, characterized in that, Self-field transmission hysteresis loss caused by main current fluctuation The specific calculation formula is as follows: i i =I majir / I c Where f is the operating frequency, N j Let be the number of superconducting tape elements in the j-th layer, μ0 be the vacuum permeability, and i i Main current relative index, I major Main current fluctuation amplitude, I c denoted as the critical current density of the superconducting cable, and n as the total number of superconducting layers.

4. The method for calculating AC loss of a three-phase integrated superconducting cable according to claim 2, characterized in that, Self-field transmission hysteresis loss caused by small current fluctuations The specific calculation formula is as follows: i i =I minor / I c in, Let be the number of the i-th type of small current fluctuation. For the self-field transmission hysteresis loss caused by the i-th type of small current fluctuation, i max N represents the number of small current types, f represents the operating frequency, and N represents the number of different types of small currents. j Let μj be the number of superconducting tape elements in the j-th layer, μ0 be the free permeability, and n be the total number of superconducting layers. c i is the critical current density of the superconducting cable. i I is a relative indicator for low current. minor This represents the amplitude of small current fluctuations.

5. The method for calculating AC loss of a three-phase integrated superconducting cable according to claim 2, characterized in that, External field transmission hysteresis loss Q generated by current mag The specific calculation formula is as follows: Among them, Q magi Let f be the external field magnetization loss of the i-th superconducting tape layer, f be the operating frequency, and B be the value of B. i Let β be the magnetic flux density at the i-th layer of the superconducting cable. i S is a relative index of magnetic induction. i Let B be the cross-sectional area of ​​the i-th layer of superconducting tape. zi and B θi J represents the axial magnetic field generated inside the i-th layer by the circumferential current and the circumferential magnetic field generated outside the i-th layer by the axial current of the i-th layer, respectively. C denoted as the critical current of the superconducting tape under the influence of a magnetic field, μ0 is the vacuum permeability, and b is half the thickness of the superconducting cable tape.

6. The method for calculating AC loss of a three-phase integrated superconducting cable according to claim 5, characterized in that, Solving for the axial magnetic field B generated inside the i-th layer by the circumferential current in the i-th layer. zi and the circumferential magnetic field B generated by the axial current of the i-th layer outside the i-th layer. θi At that time, the main current fluctuation amplitude I major Instead of calculating the current value for each layer, the specific calculation formula is as follows: Where n is the total number of superconducting layers, ε k As a relative dielectric, L pk and L pi To control the pitch, r ic and r io denoted as the inner radius and outer radius of the i-th current-carrying layer, respectively.

7. The method for calculating AC loss of a three-phase integrated superconducting cable according to claim 1, characterized in that, The specific formula for calculating the Joule heat loss is as follows: W=n p I 2 R p Where W is the Joule heat loss, n p Where I is the number of phases in the superconducting cable, I is the magnitude of the single-phase current, and R is the current in the superconducting cable. p This refers to the single-phase terminating resistor of a superconducting cable.

8. The method for calculating AC loss of a three-phase integrated superconducting cable according to claim 1, characterized in that, The specific formula for calculating the heat leakage loss is as follows: Among them, W ter Where I is the heat loss due to leakage, K is the thermal conductivity, ρ is the resistivity, and T is the temperature.

9. The method for calculating AC loss of a three-phase integrated superconducting cable according to claim 1, characterized in that, The specific steps of the method for solving the interlayer current distribution are as follows: Construct an equivalent circuit diagram of a multilayer superconducting cable, write Kirchhoff voltage equations for each phase and each layer for each order current containing harmonic components, and combine them to obtain the Kirchhoff voltage equation matrix. Based on the Kirchhoff voltage equation matrix, the voltage magnitude of each phase is solved by using the current magnitude of each phase and the current relationship between the conductive layer and the shielding layer, and the current distribution of each layer is solved by using the fact that the voltages of each layer in each phase are the same.

10. An electronic device comprising a memory, a processor, and a program stored in the memory, characterized in that, When the processor executes the program, it implements the method as described in any one of claims 1-9.

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