A Method, System, Device and Medium for Overvoltage Simulation of DC Submarine Cables

Abstract

The present invention relates to a method, system, device and medium for overvoltage simulation of a DC cable. The method includes the following steps: equally spacing and segmenting a target DC submarine cable; modeling each segment of the target DC submarine cable, and when meeting the requirements of simulation verification, combining the segment models of the target DC submarine cable to form an overvoltage simulation model of the complete target DC submarine cable; adding voltage measurement points and fault points at the segment joints of the target DC submarine cable, and based on the overvoltage simulation model of the target DC submarine cable, performing simulation verification and voltage value monitoring on each fault point to obtain the overvoltage simulation result of the target DC submarine cable. The present invention can more accurately and conveniently grasp the overvoltage characteristics of the DC cable, has practical significance for overvoltage simulation in actual projects, and can be widely applied to the electromagnetic transient simulation field of DC cable overvoltage.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic transient simulation of DC submarine cables, and particularly to an overvoltage simulation method, system, device and medium for DC submarine cables for the transmission of offshore wind power through a flexible DC system. Background Art

[0002] Wind power generation has become one of the power generation methods with the most mature technology and the greatest potential for commercial development in the field of clean energy utilization. China is rich in offshore wind power resources and is close to load centers, with great development potential. With the continuous reduction of offshore resources and the continuous progress of wind power technology, the development and utilization of far-sea wind power resources have become an inevitable trend. However, problems such as the long-distance transmission and consumption of wind power resources and the connection of isolated islands have severely restricted the efficient utilization of wind energy. The AC power transmission has a weak long-distance transmission capacity, and the conventional DC power transmission requires the support of the sending-end AC power grid and the transmitted power is not suitable for frequent fluctuations following the output of new energy, both of which have certain technical limitations. Flexible DC power transmission, with its many advantages such as independent control of active / reactive power, ability to supply power to passive networks, high decoupling from the AC power grid, convenience for multi-point collection of renewable energy, and flexible operation modes, has become the best technical means for the collection and transmission of far-sea wind power.

[0003] The transient overvoltage characteristics of a flexible DC power transmission system are important factors determining the insulation level of equipment and the air clearance, directly affecting the manufacturing difficulty of converter station equipment and DC submarine cables, the layout of converter stations, and the project cost, etc. The transient overvoltage level of a flexible DC power transmission system is related to factors such as the main wiring, main circuit parameters, insulation coordination scheme, control and protection strategy, fault location, and fault type of the flexible DC power transmission system. The development process of transient overvoltage is complex and presents characteristics completely different from those of the AC system. There has been no project operation of the offshore wind power transmitted through a flexible DC system in China, and the overvoltage level of DC submarine cables highly depends on simulation analysis. Accurately simulating the overvoltage level of DC submarine cables in a flexible DC transmission system under different operating conditions is the basis for equipment research and development and manufacturing, and also an important part of engineering design.

[0004] At present, although there are already overvoltage simulation methods for the transmission lines of flexible DC transmission systems, the transmission line equivalent method is not applicable to the simulation analysis of large-capacity, high-voltage-level, long-distance DC submarine cables, and the overvoltage characteristics and electromagnetic transient characteristics after faults of DC submarine cables are very different from those of DC transmission lines. Summary of the Invention

[0005] Aiming at the above problems, the purpose of the present invention is to provide an overvoltage simulation method, system, device and medium for DC submarine cables. By establishing a reasonable and credible overvoltage simulation model of DC submarine cables, the overvoltage characteristics of the flexible DC transmission system for million-kilowatt offshore wind power are studied, which can provide a theoretical basis for engineering design and equipment development and has great value for popularization and application.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a method for simulating overvoltage of a DC submarine cable, which includes the following steps:

[0008] Segment the target DC submarine cable at equal intervals;

[0009] Model each segment of the target DC submarine cable, and when the simulation verification requirements are met, combine the target DC submarine cable segment models to form a complete overvoltage simulation model of the target DC submarine cable;

[0010] Add voltage measurement points and fault points at the segmented locations of the target DC submarine cable, and based on the overvoltage simulation model of the target DC submarine cable, perform simulation verification and voltage value monitoring on each fault point to obtain the overvoltage simulation results of the target DC submarine cable.

[0011] Further, the method for segmenting the target DC submarine cable at equal intervals includes:

[0012] Segment the target DC submarine cable at equal intervals based on the initial value of the number of segments determined for the target DC submarine cable;

[0013] Calculate the inductance value and capacitance value of each segment of the target DC submarine cable respectively;

[0014] Based on the calculated inductance value and capacitance value, calculate the overvoltage generated on each segment of the other pole of the target DC submarine cable due to the charging of the cable capacitance when a ground fault occurs on one pole;

[0015] If the overvoltage generated on each segment meets the preset conditions, the segmentation of the target DC submarine cable is completed; otherwise, after modifying the initial value N of the number of segments, recalculate until the requirements are met.

[0016] Further, the initial value of the number of segments of the target DC submarine cable is determined according to the length of the target DC submarine cable, the simulation step size, and the load capacity.

[0017] Further, the calculation formula for the capacitance value of each segment of the target DC submarine cable is:

[0018]

[0019]

[0020] In the formula, C is the total capacitance of the target DC submarine cable; C Xis the equivalent capacitance of the X - th segmented target DC submarine cable; ε0 is the permittivity of vacuum; ε is the permittivity of the insulating material; D is the outer diameter of the insulation layer of the target DC submarine cable, in m; d is the outer diameter of the conductor of the target DC submarine cable, in m; l is the total length of the target DC submarine cable, in m;

[0021] The calculation formula for the inductance value of each segmented target DC submarine cable is:

[0022]

[0023] In the formula, L is the inductance of the target DC submarine cable; L X is the inductance of the X - th segmented target DC submarine cable, in H.

[0024] Furthermore, the calculation formula for the over - voltage generated by each segmented target DC submarine cable is:

[0025]

[0026]

[0027]

[0028] In the formula, U Cx is the capacitance voltage of the X - th segmented target DC submarine cable, in V; U dc is the steady - state operating DC voltage, in V; is the inductance voltage of the X - th segmented target DC submarine cable, in V; τ is the time constant; is the capacitance current of the X - th segmented DC submarine cable, in A; is the inductance current of the X - th segmented DC submarine cable, in A; L X is the inductance of the X - th segmented DC submarine cable, in H.

[0029] Furthermore, when modeling each segmented target DC submarine cable, the DC submarine cable model used is a T - type or π - type line equivalent model, and the modeling method is any one of the Bergeron line model, the mode - domain frequency - varying line model, and the phase - domain frequency - varying line model.

[0030] Furthermore, the method for obtaining the complete DC submarine cable over - voltage simulation model is: directly connecting the DC submarine cable models of each segmented target DC submarine cable.

[0031] In the second aspect, the present invention provides a DC submarine cable over - voltage simulation system, which includes:

[0032] A cable segmentation module, used for equally - spacing segmenting the target DC submarine cable;

[0033] A model establishment module, configured to model each segment of a target HVDC submarine cable, and combine the target HVDC submarine cable segment models to form an overvoltage simulation model of the target HVDC submarine cable when the simulation verification requirements are met;

[0034] An overvoltage simulation module, configured to add voltage measurement points and fault points at the segment joints of the target HVDC submarine cable, perform simulation verification and voltage value monitoring on each fault point based on the overvoltage simulation model of the target HVDC submarine cable, and obtain the overvoltage simulation result of the target HVDC submarine cable.

[0035] In a third aspect, the present invention provides a processing device, which at least includes a processor and a memory. A computer program is stored on the memory, and when the processor runs the computer program, the steps of the overvoltage simulation method for the HVDC submarine cable are implemented.

[0036] In a fourth aspect, the present invention provides a computer storage medium, on which computer-readable instructions are stored, and the computer-readable instructions can be executed by a processor to implement the steps of the overvoltage simulation method for the HVDC submarine cable.

[0037] Due to the above technical solutions, the present invention has the following advantages: By segmentally modeling a long-distance HVDC submarine cable, the complete DC cable is composed of several small distributed parameter models, and fault points and voltage measurement points are set at the small segments, so as to more accurately and conveniently grasp the characteristics of the HVDC submarine cable, which has more practical significance for the overvoltage simulation of actual projects. Therefore, the present invention can be widely applied to the field of electromagnetic transient simulation technology of HVDC submarine cables. Description of the Drawings

[0038] By reading the detailed description of the preferred embodiments below, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present invention. Throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0039] Figure 1 is a flowchart of an overvoltage simulation method for an HVDC submarine cable according to the present invention;

[0040] Figure 2 is an equivalent schematic diagram of capacitance and inductance of an HVDC submarine cable segment according to the present invention;

[0041] Figure 3 is an overall model schematic diagram of HVDC submarine cable segment simulation according to the present invention;

[0042] Figure 4 is a schematic diagram of a DC line model within an HVDC submarine cable segment according to the present invention;

[0043] Figure 5It is the simulation waveform diagram of fault overvoltage after adopting the segmented modeling method in the embodiment of the present invention. Detailed implementation manners

[0044] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present invention fall within the protection scope of the present invention.

[0045] It should be noted that the terms used herein are only for describing specific implementation manners and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0046] Embodiment 1

[0047] As Figure 1 shown, this embodiment provides a method for simulating overvoltage of a DC submarine cable, which includes the following steps:

[0048] (1) Segment the target DC submarine cable at equal intervals;

[0049] (2) Model each segment of the target DC submarine cable, and when the simulation verification requirements are met, combine the segmented models of the target DC submarine cable to form a complete overvoltage simulation model of the target DC submarine cable;

[0050] (3) Add voltage measurement points and fault points at the segmented positions of the target DC submarine cable, and perform simulation verification and voltage value monitoring on each fault point based on the overvoltage simulation model of the target DC submarine cable to obtain the overvoltage simulation result of the target DC submarine cable.

[0051] In a preferred embodiment, the above step (1) includes the following steps:

[0052] (1.1) Segment the target DC submarine cable at equal intervals based on the initial value of the number of segments determined for the target DC submarine cable;

[0053] Assume that the total length of a single target DC submarine cable is l, and the length of each segment is l / N. Starting from the position of the DC side outlet of the converter, they can be numbered as the 1st segment, the 2nd segment, the Xth segment, until the Nth segment in sequence;

[0054] (1.2) Calculate the inductance value and capacitance value of each segment of the target DC submarine cable respectively;

[0055] (1.3) Based on the calculated inductance value and capacitance value, calculate the overvoltage generated on each segment of the target DC submarine cable due to the charging of the cable capacitance when a ground fault occurs at one pole.

[0056] (1.4) If the overvoltage generated on each segment meets the preset conditions, the segmentation of the target DC submarine cable is completed; otherwise, after modifying the initial value N of the number of segments, return to step (1.1) until the requirements are met.

[0057] In a preferred embodiment, in the above step (1.1), the initial value of the number of segments of the target DC submarine cable is determined according to the length of the target DC submarine cable, the simulation step size, the load capacity, etc.

[0058] As a preferred embodiment, as Figure 2 shown, in the above step (1.2), the calculation formula for the capacitance value of each segment of the target DC submarine cable is:

[0059]

[0060]

[0061] where C is the total capacitance of the target DC submarine cable; C X is the equivalent capacitance of the X-th segment of the target DC submarine cable; ε0 is the permittivity of free space, i.e., 8.86×10 -12 ; ε is the relative permittivity of the insulating material; D is the outer diameter of the insulation layer of the target DC submarine cable, in m; d is the outer diameter of the conductor of the target DC submarine cable, in m; l is the total length of the target DC submarine cable, in m.

[0062] The calculation formula for the inductance value of each segment of the target DC submarine cable is:

[0063]

[0064] where L is the inductance of the target DC submarine cable; L X is the inductance of the X-th segment of the target DC submarine cable, in H.

[0065] As a preferred embodiment, in the above step (1.3), the calculation formula for the overvoltage generated on each segment of the target DC submarine cable is:

[0066]

[0067]

[0068]

[0069] where U Cxis the capacitive voltage of the Xth segmented target HVDC submarine cable, with the unit of V; U dc is the DC voltage under steady-state operation, with the unit of V; is the inductive voltage of the Xth segmented target HVDC submarine cable, with the unit of V; τ is the time constant; is the capacitive current of the Xth HVDC submarine cable, with the unit of A; is the inductive current of the Xth HVDC submarine cable, with the unit of A; L X is the inductance of the Xth HVDC submarine cable, with the unit of H.

[0070] As a preferred embodiment, in the above step (1.4), the preset condition is:

[0071] U LX <U set

[0072] wherein, U set is the preset voltage threshold determined according to engineering requirements.

[0073] As a preferred embodiment, in the above step (2), when modeling each segmented target HVDC submarine cable, the HVDC submarine cable model adopted can be a T-type or π-type line equivalent model, and the modeling method can adopt Bergeron line model, mode-domain frequency-varying line model, phase-domain frequency-varying line model, etc. The present invention does not limit this.

[0074] As a preferred embodiment, in the above step (2), when performing simulation verification on the HVDC submarine cable model of each segmented target HVDC submarine cable, the simulation verification requirements refer to that the simulation capabilities, analysis speed, model running time, data accuracy, etc. of the HVDC submarine cable model meet the preset conditions.

[0075] As a preferred embodiment, in the above step (2), the method for obtaining a complete over-voltage simulation model of the HVDC submarine cable is to directly connect the HVDC submarine cable models of each segmented target HVDC submarine cable.

[0076] In a preferred embodiment, the simulation platforms applicable to the method include but are not limited to offline simulation platforms, semi-physical digital simulation platforms, hybrid simulation platforms, etc.

[0077] Embodiment 2

[0078] In order to further verify the effectiveness and feasibility of Embodiment 1, the following further introduces Embodiment 1 through this embodiment:

[0079] In this embodiment, a model of a ±400 kV symmetrical monopolar offshore wind power transmitted through a flexible DC system is built in the power system transient simulation software PSCAD / EMTDC. The DC transmission line uses a 110-kilometer DC submarine cable. Among them, the parameters of the DC submarine cable are collected from the cable supplier when building the simulation model, so as to obtain accurate parameters of the cable part.

[0080] As Figure 3 shown, first, the entire DC submarine cable is divided. According to the capabilities of the simulator and the required simulation time, the entire DC transmission line is divided into 11 segments at intervals of 10 kilometers each, and each segment of the DC transmission line is modeled separately to obtain 11 segmented models. The simulation results show that the simulation data of the 11 segments can truly reflect the cable fault characteristics and the overvoltage level. Figure 1 In it, S represents the sending-end converter station, R represents the receiving-end converter station, Line_SegX represents the Xth segment of the DC submarine cable, Udc_segX represents the voltage of the Xth segment of the DC submarine cable, and Fau refers to the location of the fault point.

[0081] Secondly, as Figure 4 shown, each segment of the DC cable is modeled. In the small model Sea_cable3, the actual cable parameters are filled in. This model uses a frequency-variable line model in the phase domain. The elements in the transformation matrix used for analysis are functions of frequency, which is more suitable for the study of wave characteristics; fault points LINE_FLT1 and LINE_FLT2 are configured at the positive and negative poles of the DC submarine cable respectively for fault simulation at each segmented location. At the same time, measuring points Udc1 and Udc2 are added at this segment of the cable to facilitate the collection of the positive and negative pole DC submarine cable voltages for the collection, collation and calculation of overvoltage data.

[0082] As Figure 5 shown, using the overvoltage simulation method of the DC submarine cable proposed by the present invention, it can be seen from the simulation results of modeling 11 segments of small cables that the overvoltage of the actual DC submarine cable is a curve distribution, which is closer to the overvoltage condition of the cable fault in the actual project.

[0083] Embodiment 3

[0084] The above-mentioned Embodiment 1 provides a method for simulating overvoltage of a DC submarine cable. Correspondingly, this embodiment provides a system for simulating overvoltage of a DC submarine cable. The system provided in this embodiment can implement the method for simulating overvoltage of a DC submarine cable in Embodiment 1, and the system can be implemented in a software, hardware, or a combination of software and hardware manner. For example, the system can include integrated or separate functional modules or functional units to execute the corresponding steps in the methods of Embodiment 1. Since the system in this embodiment is basically similar to the method embodiment, the description process in this embodiment is relatively simple. For related parts, reference can be made to the partial description in Embodiment 1. The embodiments of the system provided in this embodiment are merely illustrative.

[0085] A system for simulating overvoltage of a DC submarine cable provided in this embodiment includes:

[0086] A cable segmentation module, configured to segment the target DC submarine cable at equal intervals;

[0087] A model establishment module, configured to model each segment of the target DC submarine cable, and combine the target DC submarine cable segment models to form an overvoltage simulation model of the target DC submarine cable when the simulation verification requirements are met;

[0088] An overvoltage simulation module, configured to add voltage measurement points and fault points at the segmentation points of the target DC submarine cable, and perform simulation verification and voltage value monitoring on each fault point based on the overvoltage simulation model of the target DC submarine cable to obtain the overvoltage simulation result of the target DC submarine cable.

[0089] Embodiment 4

[0090] This embodiment provides a processing device corresponding to the method for simulating overvoltage of a DC submarine cable provided in Embodiment 1. The processing device can be a processing device for a client, such as a mobile phone, a laptop computer, a tablet computer, a desktop computer, etc., to execute the method in Embodiment 1.

[0091] The processing device includes a processor, a memory, a communication interface, and a bus. The processor, the memory, and the communication interface are connected through the bus to complete communication with each other. The memory stores a computer program that can run on the processor. When the processor runs the computer program, it executes the method for simulating overvoltage of a DC submarine cable provided in Embodiment 1.

[0092] In some embodiments, the memory can be a high-speed random access memory (RAM: Random Access Memory), and may also include a non-volatile memory, such as at least one disk memory.

[0093] In some other embodiments, the processor may be various types of general-purpose processors such as a central processing unit (CPU), a digital signal processor (DSP), etc., which are not limited herein.

[0094] Embodiment 5

[0095] A method for simulating overvoltage of a DC submarine cable according to Embodiment 1 of the present invention may be specifically implemented as a computer program product. The computer program product may include a computer-readable storage medium having thereon computer-readable program instructions for executing the method for simulating overvoltage of a DC submarine cable described in Embodiment 1 of the present invention.

[0096] The computer-readable storage medium may be a tangible device that holds and stores instructions for use by an instruction execution device. The computer-readable storage medium may be, for example, but not limited to, an electrical storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any combination of the foregoing.

[0097] It should be noted that the flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to multiple embodiments of the present application. Each block in the flowchart or block diagram may represent a module, a program segment, or a part of code that contains one or more executable instructions for implementing a specified logical function.

[0098] Those skilled in the art should understand that the embodiments of the present invention may be provided as a method, a system, or a computer program product. Therefore, the present invention may take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, 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 flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams, 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 process or multiple processes 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 apparatus to operate in a particular manner, such that the instructions stored in the computer-readable memory produce a manufacture including an instruction device that implements the functions specified in one or more of the procedures Figure 1 or blocks Figure 1 specified in one or more of the procedures and / or blocks.

[0101] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, whereby the instructions executed on the computer or other programmable apparatus provide steps for implementing the functions specified in one or more of the procedures Figure 1 or blocks Figure 1 specified in one or more of the procedures and / or blocks.

[0102] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications or equivalent replacements can still be made to the specific embodiments of the present invention, and any modifications or equivalent replacements that do not depart from the spirit and scope of the present invention should be covered by the protection scope of the claims of the present invention.

[0103] The above embodiments are only used to illustrate the present invention, and the structures, connection methods, manufacturing processes, etc. of the components can all be changed. Any equivalent transformation and improvement made on the basis of the technical solution of the present invention should not be excluded from the protection scope of the present invention.

Claims

1. A method for simulating overvoltage of a DC submarine cable, characterized in that It includes the following steps: Segment the target DC submarine cable at equal intervals; Model each segment of the target DC submarine cable, and when the simulation verification requirements are met, combine the target DC submarine cable segment models to form an overvoltage simulation model of the complete target DC submarine cable; Add voltage measurement points and fault points at the segmented locations of the target DC submarine cable, and based on the overvoltage simulation model of the target DC submarine cable, perform simulation verification and voltage value monitoring on each fault point to obtain the overvoltage simulation results of the target DC submarine cable; The method for segmenting the target DC submarine cable at equal intervals includes: Segment the target DC submarine cable at equal intervals based on the initial value of the number of segments determined for the target DC submarine cable; Calculate the inductance value and capacitance value of each segment of the target DC submarine cable respectively; Based on the calculated inductance value and capacitance value, calculate the overvoltage generated on each segment of the other pole of the target DC submarine cable due to the charging of the cable capacitance when a ground fault occurs on one pole; If the overvoltage generated on each segment meets the preset conditions, the segmentation of the target DC submarine cable is completed; otherwise, after modifying the initial value N of the number of segments, recalculate until the requirements are met.

2. The overvoltage simulation method of a DC submarine cable as claimed in claim 1, wherein The initial value of the number of segments of the target DC submarine cable is determined according to the length of the target DC submarine cable, the simulation step size, and the load capacity.

3. The overvoltage simulation method of a DC submarine cable according to claim 1, characterized in that The calculation formula for the capacitance value of each segment of the target DC submarine cable is: Where C is the total capacitance of the target DC submarine cable; is the equivalent capacitance of the X-th section of the target DC submarine cable; is the vacuum permittivity; is the permittivity of the insulating material; D is the outer diameter of the insulation layer of the target DC submarine cable, in m; is the outer diameter of the conductor of the target DC submarine cable, in m; is the total length of the target DC submarine cable, in m; The calculation formula for the inductance value of each segment of the target DC submarine cable is: In the formula, is the inductance of the target DC submarine cable; is the inductance of the X-th section of the target DC submarine cable, with the unit of H.

4. A method for simulating overvoltage of a DC submarine cable according to claim 1, characterized in that The calculation formula for the overvoltage generated by each segment of the target DC submarine cable is: Wherein, is the capacitance voltage of the Xth target DC submarine cable section, with the unit of V; is the steady-state operating DC voltage, with the unit of V; is the inductance voltage of the Xth target DC submarine cable section, with the unit of V; τ is the time constant; is the capacitance current of the Xth DC submarine cable, with the unit of A; is the inductive current of the Xth DC submarine cable, with the unit of A; is the inductance of the Xth DC submarine cable, with the unit of H.

5. The overvoltage simulation method for a DC submarine cable according to claim 1, characterized in that, When modeling each segment of the target DC submarine cable, the DC submarine cable model used is a T-type or π-type line equivalent model, and the modeling method is any one of the Bergeron line model, the mode-domain frequency-varying line model, and the phase-domain frequency-varying line model.

6. The overvoltage simulation method of a DC submarine cable according to claim 1, characterized in that, The method for obtaining the complete DC submarine cable overvoltage simulation model is: directly connect the DC submarine cable models of each segment of the target DC submarine cable.

7. A overvoltage simulation system for DC submarine cable, characterized in that, It includes: A cable segmentation module for segmenting the target DC submarine cable at equal intervals; A model establishment module for modeling each segment of the target DC submarine cable and combining the target DC submarine cable segment models to form an overvoltage simulation model of the target DC submarine cable when the simulation verification requirements are met; An overvoltage simulation module for adding voltage measurement points and fault points at the segmented locations of the target DC submarine cable, and performing simulation verification and voltage value monitoring on each fault point based on the overvoltage simulation model of the target DC submarine cable to obtain the overvoltage simulation results of the target DC submarine cable; The segmentation of the target DC submarine cable at equal intervals includes: Segment the target DC submarine cable at equal intervals based on the initial value of the number of segments determined for the target DC submarine cable; Calculate the inductance value and capacitance value of each segment of the target DC submarine cable respectively; Based on the calculated inductance value and capacitance value, calculate the overvoltage generated on each segment of the other pole of the target DC submarine cable due to the charging of the cable capacitance when a ground fault occurs on one pole; If the overvoltage generated on each segment meets the preset conditions, the segmentation of the target DC submarine cable is completed; otherwise, after modifying the initial value N of the number of segments, recalculate until the requirements are met.

8. A processing device, the processing device at least includes a processor and a memory, and a computer program is stored on the memory, characterized in that, When the processor runs the computer program, it executes steps to implement the overvoltage simulation method for the DC submarine cable according to any one of claims 1 to 6.

9. A computer storage medium, characterized in that, Computer-readable instructions are stored thereon, and the computer-readable instructions can be executed by a processor to implement steps of the overvoltage simulation method for the DC submarine cable according to any one of claims 1 to 6.

Images