A method and device for measuring the induced voltage of a DC submarine cable sheath

Abstract

The present invention discloses a method and device for measuring the induced voltage of a DC submarine cable sheath. The present invention obtains the measured induced voltage of the standard measuring point of the DC submarine cable sheath by induction, and obtains the induced voltage of the actual measuring point of the DC submarine cable sheath according to the mapping model and the actual position of the measuring point of the DC submarine cable sheath. Compared with the traditional contact measurement, there is no need to connect in series with the submarine cable laid in a mixed way, which is safer, simpler and easier to implement.

Description

Technical Field

[0001] The present invention relates to a method and device for measuring the induced voltage of a DC submarine cable sheath, belonging to the field of submarine cable detection. Background Art

[0002] Offshore wind power is the fastest-growing green energy at the present stage. Submarine cables are one of the important devices connecting offshore wind farms and onshore power grids. The laying and installation of submarine cables are complex, the operation and maintenance are difficult, and safety issues are of utmost importance during detection. Due to the electromagnetic induction phenomenon, the alternating magnetic flux of AC submarine cables will generate an induced voltage in the metal sheath of DC submarine cables. At present, the method for detecting the induced voltage is contact measurement. To measure the induced voltage of the DC submarine cable sheath by contact measurement, a suitable grounding point position must be found, and the test system is connected in series to the submarine cable system laid in a mixed manner. The high-voltage submarine cable detection system connected in series poses great challenges to the preparation conditions for testing and the safety guarantee of personnel. Summary of the Invention

[0003] The present invention provides a method and device for measuring the induced voltage of a DC submarine cable sheath, which solves the problems existing in the contact measurement disclosed in the background art.

[0004] To solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0005] A method for measuring the induced voltage of a DC submarine cable sheath includes:

[0006] Obtaining the measured induced voltage of the standard measurement point of the DC submarine cable sheath from the induction coil;

[0007] Obtaining the induced voltage of the actual measurement point of the DC submarine cable sheath according to the measured induced voltage of the standard measurement point of the DC submarine cable sheath, the pre-constructed mapping model, and the actual measurement point position of the DC submarine cable sheath; wherein, the mapping model is a relationship model between the measured induced voltage and the actual induced voltage of the standard measurement point of the DC submarine cable sheath.

[0008] Obtaining the induced voltage of the actual measurement point of the DC submarine cable sheath according to the measured induced voltage of the standard measurement point of the DC submarine cable sheath, the pre-constructed mapping model, and the actual measurement point position of the DC submarine cable sheath includes:

[0009] Obtaining the actual induced voltage of the standard measurement point of the DC submarine cable sheath according to the measured induced voltage of the standard measurement point of the DC submarine cable sheath and the pre-constructed mapping model;

[0010] Obtaining the induced voltage of the actual measurement point of the DC submarine cable sheath according to the actual induced voltage of the standard measurement point of the DC submarine cable sheath and the actual measurement point position of the DC submarine cable sheath.

[0011] The process of pre-constructing the mapping model includes:

[0012] Obtain the theoretical induced voltage of the standard measuring point of the DC cable sheath according to the distance from the DC cable sheath to each core of the high-voltage AC power transmission cable and the frequency of the alternating current in the high-voltage AC power transmission cable;

[0013] Construct a mapping model according to the theoretical induced voltage and the contact-measured induced voltage of the standard measuring point of the DC cable sheath; wherein, the contact-measured induced voltage of the standard measuring point of the DC cable sheath is the induced voltage of the standard measuring point of the DC cable sheath obtained by the contact measurement method.

[0014] The mapping model is:

[0015] U = U2α

[0016]

[0017] In the formula, U is the actual induced voltage of the standard measuring point of the DC cable sheath, U2 is the measured induced voltage of the standard measuring point of the DC cable sheath, α is the coefficient obtained according to the theoretical induced voltage and the contact-measured induced voltage of the standard measuring point of the DC cable sheath, f is the frequency of the alternating current in the high-voltage AC power transmission cable, S A 、S B 、and S C are the distances from the DC cable sheath to the phase A, phase B, and phase C cores of the high-voltage AC power transmission cable respectively, and R a 、r, μ0, D, N, S are the sampling resistance, resistance, vacuum permeability, diameter of the wound loop, number of turns, and cross-sectional area of the induction coil respectively.

[0018] The formula for obtaining the induced voltage of the actual measuring point of the DC cable sheath is:

[0019]

[0020] In the formula, U x is the induced voltage of the actual measuring point x of the DC cable sheath, U is the actual induced voltage of the standard measuring point of the DC cable sheath, L0 is the distance between the grounding end of the DC cable sheath and the actual measuring point, and L x is the distance between the actual measuring point and the standard measuring point of the DC cable sheath, and U max is the induced voltage calibrated at the grounding end of the DC cable sheath.

[0021] A measuring device for the induced voltage of a DC cable sheath, comprising:

[0022] An acquisition module for obtaining the measured induced voltage of the standard measuring point of the DC cable sheath from the induction coil;

[0023] An induced voltage module is used to obtain the induced voltage of the actual measurement point of the DC submarine cable sheath according to the measured induced voltage of the standard measurement point of the DC submarine cable sheath, the pre-constructed mapping model, and the actual position of the measurement point of the DC submarine cable sheath; wherein, the mapping model is a relationship model between the measured induced voltage and the actual induced voltage of the standard measurement point of the DC submarine cable sheath.

[0024] An acquisition module is used to obtain the actual induced voltage of the standard measurement point of the DC submarine cable sheath according to the measured induced voltage of the standard measurement point of the DC submarine cable sheath and the pre-constructed mapping model, and obtain the induced voltage of the actual measurement point of the DC submarine cable sheath according to the actual induced voltage of the standard measurement point of the DC submarine cable sheath and the actual position of the measurement point of the DC submarine cable sheath.

[0025] It further includes a modeling module, which is used to obtain the theoretical induced voltage of the standard measurement point of the DC submarine cable sheath according to the distance from the DC submarine cable sheath to each core of the high-voltage AC transmission submarine cable and the frequency of the alternating current in the high-voltage AC transmission submarine cable; construct a mapping model according to the theoretical induced voltage and the contact-measured induced voltage of the standard measurement point of the DC submarine cable sheath; wherein, the contact-measured induced voltage of the standard measurement point of the DC submarine cable sheath is the induced voltage of the standard measurement point of the DC submarine cable sheath obtained by using the contact measurement method.

[0026] The mapping model constructed by the modeling module is:

[0027] U = U2α

[0028]

[0029] In the formula, U is the actual induced voltage of the standard measurement point of the DC submarine cable sheath, U2 is the measured induced voltage of the standard measurement point of the DC submarine cable sheath, α is the coefficient obtained according to the theoretical induced voltage and the contact-measured induced voltage of the standard measurement point of the DC submarine cable sheath, f is the frequency of the alternating current in the high-voltage AC transmission submarine cable, S A 、S B 、and S C are the distances from the DC submarine cable sheath to the cores of phase A, phase B, and phase C of the high-voltage AC transmission submarine cable respectively, and R a 、r, μ0, D, N, S are the sampling resistance, resistance, vacuum permeability, diameter of the wound ring, number of turns, and cross-sectional area of the induction coil respectively.

[0030] A computer-readable storage medium stores one or more programs, and the one or more programs include instructions that, when executed by a computing device, cause the computing device to execute the method for measuring the induced voltage of the DC submarine cable sheath.

[0031] Advantages achieved by the present invention: The present invention obtains the measured induced voltage of the standard measuring points of the DC cable sheath by induction, and obtains the induced voltage of the actual measuring points of the DC cable sheath according to the mapping model and the actual measuring point positions of the DC cable sheath. Compared with the traditional contact measurement, there is no need to connect in series with the cables laid in a mixed manner, which is safer, simpler and easier to implement. Description of the Drawings

[0032] Figure 1 is a flowchart of the method for measuring the induced voltage of the DC cable sheath;

[0033] Figure 2 is a sub-diagram of the components of the multi-magnetic-circuit coupled AC / DC cable system;

[0034] Figure 3 is the measurement model of the multi-magnetic-circuit coupled AC / DC cable system;

[0035] Figure 4 is the equivalent circuit diagram of the induction coil;

[0036] Figure 5 is the contact measurement circuit diagram;

[0037] Figure 6 is the schematic diagram for measuring the induced voltage at any measuring point. Detailed Implementation Manner

[0038] The present invention will be further described below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the protection scope of the present invention.

[0039] As Figure 1 shown, a method for measuring the induced voltage of a DC cable sheath includes the following steps:

[0040] Step 1, obtain the measured induced voltage of the standard measuring points of the DC cable sheath from the induction coil.

[0041] Step 2, obtain the induced voltage of the actual measuring points of the DC cable sheath according to the measured induced voltage of the standard measuring points of the DC cable sheath, the pre-constructed mapping model, and the actual measuring point positions of the DC cable sheath; wherein, the mapping model is the relationship model between the measured induced voltage and the actual induced voltage of the standard measuring points of the DC cable sheath.

[0042] The above method obtains the measured induced voltage of the standard measuring points of the DC cable sheath by induction, and obtains the induced voltage of the actual measuring points of the DC cable sheath according to the mapping model and the actual measuring point positions of the DC cable sheath. Compared with the traditional contact measurement, there is no need to connect in series with the cables laid in a mixed manner, which is safer, simpler and easier to implement.

[0043] In the above method, it is necessary to pre-construct a mapping model. Specifically, according to the distance from the DC cable sheath to each core of the high-voltage AC transmission cable and the frequency of the alternating current in the high-voltage AC transmission cable, the theoretical induced voltage of the standard measuring point of the DC cable sheath is obtained; according to the theoretical induced voltage of the standard measuring point of the DC cable sheath and the contact-measured induced voltage, a mapping model is constructed; wherein, the contact-measured induced voltage of the standard measuring point of the DC cable sheath is the induced voltage of the standard measuring point of the DC cable sheath obtained by using the contact measurement method.

[0044] From Figure 2 and 3 it can be seen that in an actual system, high-voltage alternating current (HVAC) transmission cables are mainly laid horizontally or in a triangular pattern. The coupling distance from the core of the HVAC cable to the metal sheath of the high-voltage direct current (HVDC) cable (i.e., the DC cable sheath) can be expressed as S j (j = A, B, C). Define the average geometric radius of the DC cable sheath as R, and the current in the core of the HVAC cable as I j (j = A, B, C). Take the point at a distance l from the terminal of the HVDC cable as the standard measuring point. Generally, l is taken as 1 m. Then, according to the principle of electromagnetic induction, the expression for the magnetic flux linkage of the DC cable sheath can be calculated as:

[0045]

[0046] In the formula, ω is the angular frequency of the alternating current in the high-voltage AC transmission cable.

[0047] When three-phase balanced alternating current I A = I, the induced voltage excited by the alternating magnetic flux of the alternating current in the cores of the three-phase HVAC cables in the space domain of the DC cable, specifically, the theoretical induced voltage U0 at the standard measuring point can be expressed as:

[0048]

[0049] In the formula, f is the frequency of the alternating current in the high-voltage AC transmission cable, k1 is the first relationship coefficient, and I is the effective value of the operating current of the high-voltage alternating current (HVAC) transmission cable.

[0050] During actual laying, the position of the cable is fixed, and S j is a constant value. Therefore, U0 and k1 are linearly related.

[0051] Simplify the cable model structure, that is, the cable only has a core, a shield, and a sheath. Place Figure 4 the induction coil at the standard measuring point. The induced electromotive force of the three-phase HVAC cables on the induction coil is e(t). The inductance and resistance of the induction coil are L and r respectively, and the sampling resistance is R a .

[0052] Let \(i\) be the loop current in the induction coil. According to Kirchhoff's voltage law, we have:

[0053]

[0054] Among them, That is

[0055] At the same time, according to the electromagnetic induction theory combined with the coil structure, \(e(t)\) satisfies:

[0056]

[0057] In the formula, \(\mu_0\), \(D\), \(N\), \(S\) are the vacuum permeability, the diameter of the wound ring, the number of turns, and the cross-sectional area of the induction coil respectively, and \(M\) is the mutual inductance coefficient between the induction coil and the HVAC three-phase submarine cable passing through it.

[0058] When \(R\) a The voltage \(U\) on Ra Can be directly obtained by the voltage division formula:

[0059]

[0060] After the coil is tested, \(U\) Ra The output voltage after integration is:

[0061]

[0062] In the formula, \(U_2\) is the measured induced voltage at the standard measuring point of the DC cable sheath, and \(k_2\) is the second relationship coefficient.

[0063] Therefore, we can get:

[0064]

[0065] Using the traditional contact measurement method, see Figure 5 , the induced voltage at the standard measuring point of the DC cable sheath that can be obtained, defined as the contact measured induced voltage, is approximately equal to the directly measured induced voltage \(U_1\) of the DC cable sheath in engineering (i.e., the actual voltage at the directly measured position 1 in the figure) and \(U_0\)

[0066] Figure 5 When the voltage of the DC cable sheath is \(u_1(t)\) (\(u_1(t)\) represents a time-varying quantity, \(U_1\) represents a phasor, and the amplitudes of the upper and lower cases are equal), \(u_1(t)\) is proportional to the distance of the standard measuring point from the terminal. Since \(l = 1m\), the current flowing through the high-voltage capacitor / capacitor \(h\) is:

[0067]

[0068] The integral transformation circuit is used to perform integral reduction on i h (t) to form the voltage u3(t);

[0069] Considering an ideal analog integrator, the relationship between u3(t) and i h (t) satisfies:

[0070]

[0071] Therefore, C h is the capacitance value of the high-voltage capacitor / capacitor h, and C1 is the capacitance value of the capacitor C1 in the figure. Since u3(t) and u1(t) differ by 180°, an inverting amplifier circuit composed of a resistor and an operational amplifier is used to perform inverting processing on u2(t) to obtain the secondary output voltage signal u3(t). The relationship between the directly measured output result u3(t) and u1(t) is obtained as follows:

[0072]

[0073] In the formula, k3 is the third relationship coefficient.

[0074] Therefore, it can be obtained that:

[0075]

[0076]

[0077] According to the above relational formula, the mapping model can be obtained as:

[0078]

[0079]

[0080] In the formula, U is the actual induced voltage of the standard measuring point of the DC submarine cable sheath, U2 is the measured induced voltage of the standard measuring point of the DC submarine cable sheath, α is the coefficient obtained based on the theoretical induced voltage and the contact-measured induced voltage of the standard measuring point of the DC submarine cable sheath, and S A 、S B 、and S C are the distances from the DC submarine cable sheath to the phase A, phase B, and phase C line cores of the high-voltage AC transmission submarine cable respectively.

[0081] When measuring the induced voltage at any point of the DC submarine cable sheath, the measured induced voltage of the standard measuring point of the DC submarine cable sheath can be obtained through the Figure 4 induction coil. According to the mapping model, the actual induced voltage of the standard measuring point of the DC submarine cable sheath can be obtained. As Figure 6As shown, according to the actual induced voltage of the standard measuring points of the DC submarine cable sheath and the actual measuring point positions of the DC submarine cable sheath, the induced voltage of the actual measuring points of the DC submarine cable sheath is obtained. Specifically: Define the distance between the actual measuring point and the standard measuring point as L x , the distance between the actual measuring point and the grounding end is L0, and the induced voltage calibrated at the grounding end is U max , the measured voltage of the standard measuring point is U min , due to the coaxial structure of the cable and considering the actual engineering application, a linear calibration method is used for calibration. Denote U min = 0%, U max = 100%. Therefore

[0082] The formula for the induced voltage of the actual measuring points of the DC submarine cable sheath is:

[0083]

[0084] In the formula, U x is the induced voltage of the actual measuring point x of the DC submarine cable sheath;

[0085] Since U min = U, the above formula can be expressed as

[0086] When measuring, the present invention only needs to obtain the induced voltage through a non-contact induction coil. Based on the preset mapping model and the actual measuring point positions of the DC submarine cable sheath, the induced voltage of the actual measuring points of the DC submarine cable sheath can be calculated without connecting in series to the submarine cables laid in a mixed manner, which is safer, simpler and easier to implement, and has good economy and practicability.

[0087] Based on the same technical solution, the present invention also discloses a virtual device of the above method, a measuring device for the induced voltage of a DC submarine cable sheath, including:

[0088] An acquisition module, configured to obtain the actual induced voltage of the standard measuring points of the DC submarine cable sheath according to the measured induced voltage of the standard measuring points of the DC submarine cable sheath and the pre-constructed mapping model, and obtain the induced voltage of the actual measuring points of the DC submarine cable sheath according to the actual induced voltage of the standard measuring points of the DC submarine cable sheath and the actual measuring point positions of the DC submarine cable sheath.

[0089] An induced voltage module, configured to obtain the induced voltage of the actual measuring points of the DC submarine cable sheath according to the measured induced voltage of the standard measuring points of the DC submarine cable sheath, the pre-constructed mapping model and the actual measuring point positions of the DC submarine cable sheath; wherein, the mapping model is a relationship model between the measured induced voltage and the actual induced voltage of the standard measuring points of the DC submarine cable sheath.

[0090] A modeling module, configured to obtain the theoretical induced voltage of the standard measurement points on the DC submarine cable sheath based on the distances from the DC submarine cable sheath to each core of the high-voltage AC power transmission submarine cable, as well as the angular frequency and frequency of the alternating current in the high-voltage AC power transmission submarine cable; construct a mapping model based on the theoretical induced voltage of the standard measurement points on the DC submarine cable sheath and the contact-measured induced voltage; wherein, the contact-measured induced voltage of the standard measurement points on the DC submarine cable sheath is the induced voltage of the standard measurement points on the DC submarine cable sheath obtained by using the contact measurement method.

[0091] The mapping model constructed by the modeling module is:

[0092] U = U2α

[0093]

[0094] In the formula, U is the actual induced voltage of the standard measurement points on the DC submarine cable sheath, U2 is the measured induced voltage of the standard measurement points on the DC submarine cable sheath, α is the coefficient obtained based on the theoretical induced voltage and the contact-measured induced voltage of the standard measurement points on the DC submarine cable sheath, f is the frequency of the alternating current in the high-voltage AC power transmission submarine cable, S A 、S B 、and S C are respectively the distances from the DC submarine cable sheath to the cores of phase A, phase B, and phase C of the high-voltage AC power transmission submarine cable, and R a 、r, μ0, D, N, and S are respectively the sampling resistance, resistance, vacuum permeability, diameter of the wound ring, number of turns, and cross-sectional area of the induction coil.

[0095] The above device can be a software, loaded in a controller, which cooperates with the Figure 4 induction coil to effectively achieve non-contact measurement of the induced voltage at any position of the DC submarine cable sheath. Compared with the traditional contact measurement, it is safer, simpler, and easier to implement.

[0096] Based on the same technical solution, the present invention also discloses a computer-readable storage medium, which stores one or more programs. The one or more programs include instructions, and when the instructions are executed by a computing device, the computing device is caused to execute the method for measuring the induced voltage of the DC submarine cable sheath.

[0097] Based on the same technical solution, the present invention also discloses a computer device, including one or more processors and one or more memories. One or more programs are stored in the one or more memories and are configured to be executed by the one or more processors. The one or more programs include instructions for executing the method for measuring the induced voltage of the DC submarine cable sheath.

[0098] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memory, CD-ROM, optical memory, etc.) that contain computer-usable program code.

[0099] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, as well as the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate means for implementing the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0100] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including instruction means that implement the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0101] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0102] The above are only embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention pending approval.

Claims

1. A method for measuring the induced voltage of a DC submarine cable sheath, characterized in that, Including: Obtaining the measured induced voltage of the standard measuring point of the DC submarine cable sheath from the induction coil; According to the measured induced voltage of the standard measuring point of the DC submarine cable sheath and the pre-constructed mapping model, obtaining the actual induced voltage of the standard measuring point of the DC submarine cable sheath, and according to the actual induced voltage of the standard measuring point of the DC submarine cable sheath and the actual measuring point position of the DC submarine cable sheath, obtaining the induced voltage of the actual measuring point of the DC submarine cable sheath; wherein, the mapping model is a relationship model between the measured induced voltage and the actual induced voltage of the standard measuring point of the DC submarine cable sheath; The process of pre-constructing the above mapping model includes: Obtaining the theoretical induced voltage of the standard measuring point of the DC submarine cable sheath according to the distance from the DC submarine cable sheath to each core of the high-voltage AC transmission submarine cable and the frequency of the alternating current in the high-voltage AC transmission submarine cable; constructing a mapping model according to the theoretical induced voltage of the standard measuring point of the DC submarine cable sheath and the contact-measured induced voltage; wherein, the contact-measured induced voltage of the standard measuring point of the DC submarine cable sheath is the induced voltage of the standard measuring point of the DC submarine cable sheath obtained by the contact measurement method; The mapping model is: U = U2α Wherein, U is the actual induced voltage at the standard measurement point of the DC submarine cable sheath, U2 is the measured induced voltage at the standard measurement point of the DC submarine cable sheath, α is the coefficient obtained based on the theoretical induced voltage and the contact-measured induced voltage at the standard measurement point of the DC submarine cable sheath, f is the frequency of the alternating current in the high-voltage AC transmission submarine cable, S A 、S B 、and S C are the distances from the DC submarine cable sheath to the phase A, phase B, and phase C core conductors of the high-voltage AC transmission submarine cable respectively, R a 、r, μ0, D, N, and S are the sampling resistance, resistance, vacuum permeability, diameter of the wound loop, number of turns, and cross-sectional area of the induction coil respectively; The formula for obtaining the induced voltage of the actual measuring point of the DC submarine cable sheath is: Where, U x is the induced voltage at the actual measurement point x of the DC submarine cable sheath, L0 is the distance between the grounding end of the DC submarine cable sheath and the actual measurement point, and L x is the distance between the actual measurement point and the standard measurement point of the DC submarine cable sheath, and U max is the induced voltage calibrated at the grounding end of the DC submarine cable sheath.

2. A device for measuring the induced voltage of a DC submarine cable sheath, characterized in that, Including: An obtaining module for obtaining the measured induced voltage of the standard measuring point of the DC submarine cable sheath from the induction coil; An induced voltage module, which obtains the actual induced voltage of the standard measuring point of the DC submarine cable sheath according to the measured induced voltage of the standard measuring point of the DC submarine cable sheath and the pre-constructed mapping model, and obtains the induced voltage of the actual measuring point of the DC submarine cable sheath according to the actual induced voltage of the standard measuring point of the DC submarine cable sheath and the actual measuring point position of the DC submarine cable sheath; wherein, the mapping model is a relationship model between the measured induced voltage and the actual induced voltage of the standard measuring point of the DC submarine cable sheath; A modeling module for obtaining the theoretical induced voltage of the standard measuring point of the DC submarine cable sheath according to the distance from the DC submarine cable sheath to each core of the high-voltage AC transmission submarine cable and the frequency of the alternating current in the high-voltage AC transmission submarine cable; constructing a mapping model according to the theoretical induced voltage of the standard measuring point of the DC submarine cable sheath and the contact-measured induced voltage; wherein, the contact-measured induced voltage of the standard measuring point of the DC submarine cable sheath is the induced voltage of the standard measuring point of the DC submarine cable sheath obtained by the contact measurement method; The mapping model is: U = U2α Wherein, U is the actual induced voltage at the standard measuring point of the DC submarine cable sheath, U2 is the measured induced voltage at the standard measuring point of the DC submarine cable sheath, α is the coefficient obtained based on the theoretical induced voltage and the contact-measured induced voltage at the standard measuring point of the DC submarine cable sheath, f is the frequency of the alternating current in the high-voltage AC transmission submarine cable, S A 、S B 、and S C are the distances from the DC submarine cable sheath to the phase A, phase B, and phase C core wires of the high-voltage AC transmission submarine cable respectively, R a 、r, μ0, D, N, and S are the sampling resistance, resistance, vacuum permeability, diameter of the wound loop, number of turns, and cross-sectional area of the induction coil respectively; The formula for obtaining the induced voltage of the actual measuring point of the DC submarine cable sheath is: Where, U x is the induced voltage at the actual measurement point x of the DC submarine cable sheath, L0 is the distance between the grounding end of the DC submarine cable sheath and the actual measurement point, and L x is the distance between the actual measurement point and the standard measurement point of the DC submarine cable sheath, and U max is the induced voltage calibrated at the grounding end of the DC submarine cable sheath.

3. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores one or more programs, and the one or more programs include instructions that, when executed by a computing device, cause the computing device to execute the method according to claim 1.

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