Constant voltage simulation system and method for offshore wind power cables

Abstract

This application provides a constant-voltage simulation system and method for offshore wind power cables, belonging to the field of offshore wind power technology. The system comprises: a transformer model for simulating a target transformer based on a preset approach; a cable model for determining cable components and their associated parameters within the simulated cable; and a wind power model for simulating and constructing a wind turbine. The cable model is connected to the transformer model and the wind power model. This enables simulation analysis of offshore wind power cables, resolving the prior art issue of difficulty in accurately estimating submarine cable line losses.

Description

Technical Field

[0001] The present application relates to the field of offshore wind power, and specifically to a constant voltage simulation system and method for offshore wind power cables. Background Art

[0002] Offshore wind power generation is gaining increasing popularity in various countries due to its advantages, including abundant wind energy, low surface roughness, good stability, long lifespan, and high power generation capacity. However, offshore power generation projects are also expensive, and this cost is closely related to the length of submarine cables and the depth of the sea.

[0003] High-voltage submarine cables are a crucial link connecting offshore wind power plants. Over long distances, these cables incur some line loss. However, offshore wind power output fluctuates constantly, making it difficult to accurately assess submarine cable line loss.

[0004] To reduce the construction costs of offshore power generation projects, it is necessary to comprehensively consider factors such as line loss, required voltage, and cable length. However, line loss is difficult to accurately estimate, and there is currently a lack of systems to prepare for this prediction. Summary of the Invention

[0005] In view of this, the present application provides a constant voltage simulation system and method for offshore wind power cables, which solves the technical problem in the prior art that it is difficult to accurately estimate the line loss of submarine cables.

[0006] According to one aspect of the present application, a constant voltage simulation system for offshore wind power cables is characterized by comprising:

[0007] The transformer model is used to simulate the target transformer based on a preset approach; the cable model is used to determine the cable elements and their related parameters in the simulated cable; the wind power model is used to simulate and construct a wind turbine; wherein the cable model connects the transformer model and the wind power model.

[0008] In a possible embodiment, the target transformer includes a first target transformer and a second target transformer, and the transformer model includes: a classical approach simulation unit for simulating the first target transformer based on the classical approach; and an electromagnetic transient simulation unit for simulating the second target transformer based on the electromagnetic transient.

[0009] In a possible embodiment, the cable model includes: a cable structure simulation unit, used to set cable elements in the simulated cable; and a parameter setting simulation unit, used to set relevant parameters of the cable elements.

[0010] In a possible embodiment, the cable structure simulation unit includes: a conductor simulation subunit, used to determine the conductor and its material; an insulation layer simulation subunit, used to construct the insulation layer outside the conductor; a metal sheath simulation subunit, used to set a metal protective sheath located outside the insulation layer; and an armor simulation subunit, used to set armor on the outside of the metal protective sheath.

[0011] In a possible embodiment, the parameter setting simulation unit includes: a cable type simulation subunit, used to determine the type of the transmission line; and a parameter setting simulation subunit, used to set relevant parameters of the cable.

[0012] In a possible embodiment, the wind power model includes: a wind source component simulation unit, used to determine the wind source component in the wind turbine; a mechanical generator set simulation unit, used to determine the mechanical generator set in the wind turbine; and a speed regulator simulation unit, used to determine the speed regulator in the wind turbine.

[0013] In a possible embodiment, the wind power model further includes: a simulation analysis module for determining the loss of the submarine cable under a constant pressure state.

[0014] In a possible embodiment, the simulation analysis module includes: a voltage loss analysis unit for determining the voltage loss of the submarine cable under a constant voltage state; and a cable efficiency analysis unit for determining the cable efficiency of the submarine cable.

[0015] As another aspect of the present application, a constant voltage simulation method for a wind power cable is provided, comprising: simulating a target transformer based on a preset path through a transformer model; determining cable elements and related parameters in the simulated cable through a cable model; and constructing a wind turbine through wind power model simulation; wherein the cable model is connected to the transformer model and the wind power model.

[0016] In a possible embodiment, the step of simulating the target transformer based on a preset approach using a transformer model includes: simulating the first target transformer based on a classical approach using a classical approach simulation unit; and simulating the second target transformer based on an electromagnetic transient simulation unit.

[0017] Compared to existing technologies, this application provides a constant-voltage simulation system and method for offshore wind power cables, belonging to the field of offshore wind power technology. The system includes: a transformer model for simulating a target transformer based on a preset path; a cable model for determining cable components and their associated parameters within the simulated cable; and a wind power model for simulating and constructing a wind turbine. The cable model is connected to the transformer model and the wind power model. This enables simulation analysis of offshore wind power cables, resolving the prior art issue of difficulty in accurately estimating submarine cable line losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other purposes, features, and advantages of the present application will become more apparent through a more detailed description of the embodiments of the present application in conjunction with the accompanying drawings. The accompanying drawings are intended to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation of the present application. In the drawings, the same reference numerals generally represent the same components or steps.

[0019] Figure 1 FIG2 is a schematic diagram showing the composition of a constant voltage simulation system for offshore wind power cables provided in one embodiment of the present application;

[0020] Figure 2 This is a schematic diagram of the connection between an offshore wind farm and a shore involved in an embodiment of the present application;

[0021] Figure 3 1 is a schematic diagram of cable loss according to an embodiment of the present application;

[0022] Figure 4 This is a schematic diagram of a constant voltage simulation model of an offshore wind power cable according to an embodiment of the present application;

[0023] Figure 5 This is a schematic diagram of parameter settings for a constant voltage simulation model of an offshore wind power cable according to an embodiment of the present application;

[0024] Figure 6 is an input wind speed curve diagram involved in Example 1 of the present application;

[0025] Figure 7 is a graph of onshore power and offshore wind farm power under simulation conditions according to an embodiment of the present application;

[0026] Figure 8 is a power loss curve diagram under simulation conditions involved in an embodiment of the present application;

[0027] Figure 9 FIG2 is a flow chart of a constant voltage simulation system method for an offshore wind power cable provided by an embodiment of the present application;

[0028] Figure 10 Shown is a structural schematic diagram of an electronic device provided in one embodiment of the present application.

[0029] Specific embodiment

[0030] In the description of the application, the meaning of "multiple" is at least two, for example two, three, etc., unless otherwise clearly and specifically limited. In the embodiments of the present application, all directional indications (such as up, down, left, right, front, back, top, bottom ...) are only used to explain the relative position relationship, motion situation, etc. between each component under a certain specific posture (as shown in the drawings). If this specific posture changes, this directional indication also changes accordingly. In addition, the terms "comprise" and "have" and any deformation thereof are intended to cover non-exclusive inclusion. For example, the process, method, system, product or equipment comprising a series of steps or units is not limited to the steps or units listed, but optionally also includes the steps or units not listed, or optionally also includes other steps or units inherent to these processes, methods, products or equipment.

[0031] In addition, references to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of such phrases in various places in the specification does not necessarily refer to the same embodiment, nor does it necessarily refer to independent or alternative embodiments that are mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0032] The following will be combined with the accompanying drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of this application.

[0033] Figure 1 FIG. 1 is a schematic diagram showing the composition of a constant voltage simulation system for offshore wind power cables provided by an embodiment of the present application. Figure 1 As shown in the figure, the constant voltage simulation system for offshore wind power cables includes:

[0034] Transformer model 01, used to simulate the target transformer based on a preset approach;

[0035] This embodiment uses Power Systems Computer Aided Design (PSCAD) for simulation. PSCAD is a popular software used for power system research worldwide, and electromagnetic transient simulation is the core of its operation. In PSCAD, the target transformer can be created through a preset path.

[0036] Cable model 02, used to determine the cable components and their related parameters in the simulated cable;

[0037] This embodiment requires the creation of correct cable components and their corresponding related parameters in the power system. Generally, cable components can be created by selecting "create table" in PSCAD. Parameters such as the cable component name, cable length, conductor data, and steady-state frequency can be set. Cable components are essentially a type of connecting wire component with a variety of shapes and adjustable sizes. When adding two cable interface components with the same name to the circuit, the name of the cable interface component must be consistent with the name of the cable configuration component. It should be noted that unlike overhead lines, cables do not support direct connection mode.

[0038] Furthermore, in PSCAD, selecting Edit Definition opens the transmission line definition editor. In the definition editor, you can set the transmission line model and parameters. PSCAD provides three transmission line models: the Bergeron model, the Frequency Dependent (Phase) model, and the Frequency Dependent (Mode) model.

[0039] Wind power model 03, used to simulate and build wind turbines.

[0040] Wind turbines are the core component of wind power generation systems. They convert wind energy into mechanical work, which in turn drives the rotor, ultimately outputting alternating current. In a real offshore wind farm, a wind turbine typically consists of a rotor, generator (including the device), stabiliser (tail), tower, speed limiter, and energy storage device.

[0041] The cable model is connected to the transformer model and the wind power model. The wind power model, cable model and transformer model are sequentially connected to form a constant voltage simulation system for wind power cables.

[0042] The target transformer includes a first target transformer and a second target transformer, and the transformer model includes:

[0043] A classical approach simulation unit, configured to simulate a first target transformer based on a classical approach;

[0044] The electromagnetic transient simulation unit is used for simulating the second target transformer based on electromagnetic transient.

[0045] The classical approach and the electromagnetic transient approach. The classical approach considers windings on independent, identical transformer cores. That is, each individual phase is independent of the others, and individual transformers are unrelated. The electromagnetic transient approach, however, takes into account the mutual influence of these windings; thus, it can reasonably simulate both three-phase and five-phase transformer configurations. The non-linear nature of the core within each module is a fundamental difference. In the classical approach, core saturation is simulated by applying external currents to selected windings. The electromagnetic transient approach uses specific interpolated values ​​and separate linearized current phase curves to represent this behavior. The classical approach is limited to single-phase devices, with various groups wound on a single leg. The transient simulation method, however, considers the core geometry and the coupling characteristics between the phases. Beyond the obvious differences mentioned above, the most fundamental difference between the first and second target transformers is the core characteristics.

[0046] The first target transformers simulated by the classical approach include single-phase autotransformer, three-phase star-connected autotransformer, single-phase two-winding transformer, single-phase three-winding transformer, three-phase two-winding transformer, three-phase three-winding transformer, and three-phase four-winding transformer; the second target transformers simulated by the electromagnetic transient approach include single-phase two-winding UMEC transformer, single-phase three-winding UMEC transformer, single-phase four-winding UMEC transformer, and 3 / 5-arm UMEC transformer.

[0047] Specifically, the cable model includes:

[0048] a cable structure simulation unit, used for setting cable elements in the circuit;

[0049] The parameter setting simulation unit is used to set relevant parameters of the cable element.

[0050] Among them, the cable structure simulation unit includes:

[0051] The conductor simulation subunit is used to determine the conductor and its material. The main function of the conductor is to transmit current. The conductor can be composed of a single material or a composite of multiple materials. The materials of the conductor are diverse, and commonly used materials are copper and aluminum.

[0052] The insulating layer simulation subunit is used to construct an insulating layer outside the conductor; the insulating layer can prevent the current in the conductor from being conducted to the outside, thereby endangering personal safety and causing pollution to the surrounding environment.

[0053] The metal sheath simulation subunit is used to set a metal protective sheath located outside the insulating layer; the metal sheath can prevent conductive factors such as water from affecting the conduction of current, and make the wire have a stronger appearance, extend its service life, and make it more stable.

[0054] The armor simulation subunit is used to apply armor to the outer surface of the metal protective sheath. Armor increases the strength of the conductor surface and is most commonly made of steel, though other materials include stainless steel and aluminum. Steel armor can withstand higher pressures if formed into long ribbons, while filaments provide improved stretchability.

[0055] The parameter setting simulation unit includes:

[0056] The cable type simulation subunit is used to determine the type of the transmission line; the transmission line model can be one of the Bergeron model, the Frequency Dependent Phase model, and the Frequency Dependent Mode model.

[0057] The parameter setting simulation subunit is used to set the relevant parameters of the cable, at least to set the cable length, number of conductors, steady-state frequency and other detailed parameters.

[0058] Specifically, the wind power model includes:

[0059] The wind source component simulation unit is used to determine the wind source component in the wind turbine; the wind source component can simulate every condition of the wind, such as wind speed, slope, noise, shock absorber, etc.

[0060] The mechanical generator set simulation unit is used to determine the mechanical generator set in the wind turbine; the mechanical generator set includes an input interface and an output interface.

[0061] The speed regulator simulation unit is used to determine the speed regulator in the wind turbine.

[0062] For dynamic simulation, the wind speed simulation is generally carried out for 24 hours; therefore, the wind speed must consider the change from the cut-in wind speed to the cut-out wind speed in order to study the response of the wind turbine under different wind conditions.

[0063] The wind power model further includes a simulation analysis module for determining the loss of the submarine cable under a constant voltage state. In this embodiment, the simulation analysis module includes a voltage loss analysis unit for determining the voltage loss of the submarine cable under a constant voltage state; and a cable efficiency analysis unit for determining the cable efficiency of the submarine cable.

[0064] The simulation analysis module is used to analyze the power loss of high-voltage submarine cables under constant voltage conditions. Figure 2-3 , Figure 2 This is a schematic diagram of the connection between an offshore wind farm and the shore involved in an embodiment of the present application. Figure 3Schematic diagram of cable loss in one embodiment of the present application. Figure 2 As shown, offshore wind farm, offshore transformer (Vfarm-V1), submarine cable (ExportCable), onshore transformer (V2-V grid ) and the onshore grid are connected in sequence to form a complete network connecting the wind farm and the land. Figure 3 It can be seen that during the transmission process through the submarine cable, the voltage drops from V1 to V2.

[0065] Assume that the voltage of the onshore grid is fixed and its value is equal to its nominal value V grid , and assuming that the transformer connected to the grid is an ideal transformer with a transformation ratio of k, the voltage V2 of the onshore grid is: V2=k·V grid ;

[0066] The offshore transformer connected to the offshore wind farm is also assumed to be ideal, allowing the voltage on the cable side to exceed the cable voltage on the shore side by 10%. The offshore voltage V1 is: V1=V2·α·e jβ ;

[0067] Where α is the ratio between the voltage amplitude at the onshore grid and the grid section of the cable, and β represents the phase angle (in radians) between the voltages at both ends. It is also assumed that reactive power consumption can be controlled so that the voltage v1 at the offshore wind farm in the above formula is within the permitted range. The voltage source v1 represents the aggregate effect of the transformer, wind turbine converter, and reactive power compensation equipment. The cable is represented using its exact PI equivalent, which accurately accounts for distributed parameter effects and thus for variations in voltage and current along the cable.

[0068] The behavior of a cable is defined by its length L, the series impedance per unit length Z and the shunt admittance Y:

[0069] (1)

[0070] (2)

[0071] This embodiment divides the cable into n parts for evaluating the internal voltage and current.

[0072] According to the PUL parameters, we can get the cable admittance matrix:

[0073] (3)

[0074] in , .

[0075] Using the admittance matrix and the known terminal voltage, the current at the cable terminals can be calculated as:

[0076] (4)

[0077] For the calculation of cable losses, based on the solution of the current at the end of the cable, the cable active and reactive power transmitted from the offshore wind farm and absorbed by the onshore grid is calculated as follows:

[0078] , (5)

[0079] , (6)

[0080] And the cable loss is (7)

[0081] In order to evaluate the voltage and current at N internal nodes, the cable is subdivided into N segments of equal length. The admittance matrix can be calculated using the above formula and the node analysis method is used to assemble the global admittance matrix.

[0082] Analysis is used to calculate internal voltages and currents. This method is used to monitor current and voltage along the cable. Segmentation can also be used to account for changes in cable parameters along the route, such as changes in resistance due to temperature changes.

[0083] Cable efficiency is defined as the ratio of the power transmitted by the grid to the power generated by the grid. The operation is to operate the system in order to maximize the cable efficiency. The cable efficiency is expressed as follows:

[0084] (8)

[0085] It is worth noting that based on , so for a given instantaneous wind power generation, operation at maximum cable efficiency is equivalent to operation with minimum cable loss. To analyze the efficiency, formula (4) is rewritten as follows:

[0086] (9)

[0087] where ξ is the voltage regulation required to achieve a given active and reactive power

[0088] (10)

[0089] In (9), A, B, and ξ are all complex quantities, but v2 can be assumed to be a real number, so we can write

[0090]

[0091] (11)

[0092]

[0093] (12)

[0094] The cable efficiency can be further expressed as follows:

[0095] (13)

[0096] It can be seen from formula (13) that the cable efficiency, including its maximum value, is independent of the operating voltage v2, while for a given efficiency, the operating voltage v2 can determine the transmitted power.

[0097] The constant voltage simulation of offshore wind power cables obtained based on the above-mentioned scheme in this embodiment is as follows: Figure 4 As shown, Figure 4 This is a schematic diagram of a constant voltage simulation model of an offshore wind power cable according to an embodiment of the present application. Figure 4 As shown in Figure 1, the constant voltage simulation of offshore wind power cables includes offshore wind farms, offshore transformers, submarine cables, onshore transformers, and onshore power grids.

[0098] Based on the constant voltage simulation model of offshore wind power cables, a simulation analysis under constant voltage is conducted. Specifically, under the condition of voltage level of 6KV, Figure 5 This is a schematic diagram of parameter settings for a constant voltage simulation model of an offshore wind power cable according to an embodiment of the present application, corresponding to conditions of a load of 10 MW and a cable length of 100 km. Figure 5 The cable number shown is Cable#1, the conductor radius is 0.0028m, the distance from the insulation layer to the conductor center is 0.0262m, and the distance from the metal protective sheath to the conductor center is 0.028m.

[0099] Specific simulation analysis results refer to Figure 6-8 ,in Figure 6 This is the input wind speed curve diagram involved in Example 1 of this application. Figure 7 is a graph showing onshore power and offshore wind farm power under simulation conditions according to an embodiment of the present application. Figure 8 This is a power loss curve diagram under simulation conditions according to an embodiment of the present application. Figure 7 Indicates that when the input wind speed is Figure 6 The graph of onshore power P2 and offshore wind farm power P1 is shown as follows: Figure 8 It can be seen that the cable loss fluctuates between 2MW and 3MW.

[0100] When the voltage is 6kV, when the simulation conditions are set to a load of 1MW and a cable length of 100km, the cable loss fluctuates between 2MW and 3MW; when the simulation conditions are set to a load of 10MW and a cable length of 50km, the cable loss fluctuates between 2MW and 2.5MW; when the simulation conditions are set to a load of 10MW and a cable length of 20km, the cable loss fluctuates between 1.5MW and 2MW.

[0101] When the voltage is 12kV, when the simulation conditions are set to a load of 10MW and a cable length of 100km, the cable loss fluctuates between 3MW and 4MW; when the voltage is 18kV, when the simulation conditions are set to a load of 10MW and a cable length of 100km, the cable loss fluctuates between 3MW and 4MW.

[0102] From the above simulation analysis results, it can be seen that the cable loss at 18kV is higher than that at 6kV, but it is slightly lower than that at 12kV. The reason may be that the cable loss is mainly determined by two factors: the voltage level of the cable and the cable length. The influence of the two is not proportional. The radius of the cables corresponding to 12kV and 18kV is different, which results in the voltage level being increased but the loss being reduced.

[0103] This embodiment, through the above-mentioned solution, provides a constant-voltage simulation system for offshore wind power cables. The system includes a transformer model for simulating a target transformer based on a preset approach; a cable model for simulating cable components and their associated parameters within a circuit; and a wind power model for simulating the construction of a wind turbine. This enables simulation analysis of offshore wind power cables, resolving the existing technical issue of difficulty in accurately estimating submarine cable line losses.

[0104] As another aspect of the present application, a constant voltage simulation method for a wind power cable is provided. Figure 9 FIG. 1 is a flow chart of a constant voltage simulation system method for an offshore wind power cable provided by an embodiment of the present application, as shown in FIG. Figure 9 The method shown includes:

[0105] Step S101, simulating a target transformer based on a preset approach using a transformer model;

[0106] This embodiment uses Power Systems Computer Aided Design (PSCAD) for simulation. PSCAD is a popular software used for power system research worldwide, and electromagnetic transient simulation is the core of its operation. In PSCAD, the target transformer can be created through a preset path.

[0107] Specifically, the first target transformer is simulated based on the classical approach by the classical approach simulation unit; and the second target transformer is simulated based on the electromagnetic transient by the electromagnetic transient simulation unit.

[0108] The first target transformers simulated by the classical approach include single-phase autotransformer, three-phase star-connected autotransformer, single-phase two-winding transformer, single-phase three-winding transformer, three-phase two-winding transformer, three-phase three-winding transformer, and three-phase four-winding transformer; the second target transformers simulated by the electromagnetic transient approach include single-phase two-winding UMEC transformer, single-phase three-winding UMEC transformer, single-phase four-winding UMEC transformer, and 3 / 5-arm UMEC transformer.

[0109] Step S102, simulating cable components and related parameters in the circuit using a cable model;

[0110] This embodiment requires the creation of correct cable components and their corresponding related parameters in the power system. Generally, cable components can be created by selecting "create table" in PSCAD. Parameters such as the cable component name, cable length, conductor data, and steady-state frequency can be set. Cable components are essentially a type of connecting wire component with a variety of shapes and adjustable sizes. When adding two cable interface components with the same name to the circuit, the name of the cable interface component must be consistent with the name of the cable configuration component. It should be noted that unlike overhead lines, cables do not support direct connection mode.

[0111] Step S103: constructing a wind turbine through wind power model simulation.

[0112] Wind turbines are the core component of wind power generation systems. They convert wind energy into mechanical work, which in turn drives the rotor, ultimately outputting alternating current. In a real offshore wind farm, a wind turbine typically consists of a rotor, generator (including the device), stabiliser (tail), tower, speed limiter, and energy storage device.

[0113] Through the above steps, this embodiment simulates the target transformer using a transformer model based on a preset path; simulates the cable components and their related parameters in the circuit using a cable model; and constructs a wind turbine using a wind power model. This enables simulation analysis of offshore wind power cables, resolving the existing technical issue of difficulty in accurately estimating submarine cable line losses.

[0114] Below, reference Figure 10 To describe the electronic device according to the embodiment of the present application. Figure 10 Shown is a structural schematic diagram of an electronic device provided in one embodiment of the present application.

[0115] like Figure 10 As shown, electronic device 600 includes one or more processors 601 and memory 602 .

[0116] The processor 601 may be a central processing unit (CPU) or other forms of processing units having data processing capabilities and / or information execution capabilities, and may control other components in the electronic device 600 to perform desired functions.

[0117] The memory 602 may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory. The non-volatile memory may include, for example, read-only memory (ROM), a hard disk, flash memory, etc. One or more computer program information may be stored on the computer-readable storage medium, and the processor 601 may execute the program information to implement the constant voltage simulation method for a wind power cable according to the various embodiments of the present application described above, or other desired functions.

[0118] In one example, the electronic device 600 may further include an input device 603 and an output device 604 , and these components are interconnected via a bus system and / or other forms of connection mechanisms (not shown).

[0119] The input device 603 may include, for example, a keyboard, a mouse, and the like.

[0120] The output device 604 can output various information to the outside. The output device 604 can include, for example, a display, a communication network and a remote output device connected thereto.

[0121] Of course, to simplify, Figure 10 Only some of the components related to the present application in the electronic device 600 are shown, and components such as a bus, an input / output interface, etc. are omitted. In addition, the electronic device 600 may further include any other appropriate components according to specific application scenarios.

[0122] In addition to the above-mentioned methods and devices, an embodiment of the present application may also be a computer program product, which includes computer program information, which, when executed by a processor, enables the processor to execute the steps of the constant voltage simulation method for wind power cables according to various embodiments of the present application described in this specification.

[0123] The computer program product may be written in any combination of one or more programming languages ​​to implement the program code for performing the operations of the embodiments of the present application, including object-oriented programming languages ​​such as Java, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0124] In addition, an embodiment of the present application may also be a computer-readable storage medium on which computer program information is stored. When the computer program information is executed by a processor, the processor executes the steps in the constant voltage simulation method of wind power cables according to various embodiments of the present application in this specification.

[0125] The computer-readable storage medium may be any combination of one or more readable media. The readable medium may be a readable signal medium or a readable storage medium. The readable storage medium may include, for example, but is not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or device, or any combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: an electrical connection having one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof.

[0126] The basic principles of the present application have been described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, and effects mentioned in this application are merely illustrative and not restrictive, and it should not be assumed that these advantages, strengths, and effects are required of each embodiment of this application. In addition, the specific details disclosed above are merely illustrative and facilitating understanding, and are not restrictive. The above details do not limit this application to necessarily being implemented using the above specific details.

[0127] The block diagrams of the devices, devices, equipment, and systems involved in this application are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As will be appreciated by those skilled in the art, these devices, devices, equipment, and systems can be connected, arranged, or configured in any manner. Words such as "include," "comprise," "have," and the like are open-ended words, meaning "including but not limited to," and can be used interchangeably therewith. The words "or" and "and" used herein refer to the words "and / or" and can be used interchangeably therewith, unless the context clearly indicates otherwise. The word "such as" used herein refers to the phrase "such as but not limited to," and can be used interchangeably therewith.

[0128] It should also be noted that in the apparatus, device, and method of the present application, each component or each step can be decomposed and / or recombined, and such decomposition and / or recombination should be regarded as equivalent solutions of the present application.

[0129] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present application. Therefore, the present application is not intended to be limited to the aspects shown herein, but rather to be applied in the widest sense consistent with the principles and novel features of the present invention.

[0130] The above description is only a preferred embodiment of the invention of this application and is not intended to limit the invention of this application. Any modifications, equivalent substitutions, etc. made within the spirit and principles of the invention of this application should be included in the scope of protection of the invention of this application.

Claims

1. A constant voltage simulation system for offshore wind power cables, characterized in that: include: A transformer model, used to simulate a target transformer based on a preset approach; Cable model, used to determine the cable components and their related parameters in the simulated cable; Wind power model, used to simulate and build wind turbines; Wherein, the cable model is connected to the transformer model and the wind power model; The wind power model includes: a simulation analysis module for determining the loss of submarine cables under constant pressure; The cable loss is ; Wherein, Ploss represents cable loss, Re{} represents the real part of the complex number, V1 represents the voltage of the offshore wind farm, V2 represents the voltage of the onshore power grid, I1 represents the current of the offshore wind farm, I2 represents the current of the onshore power grid, and * represents the conjugate operation of the complex number; Where V2=k·V grid , where V grid is the nominal voltage of the onshore power grid, V1: V1=V2·α·e jβ ; Where α is the ratio between the voltage amplitude on the onshore grid side and the grid section of the cable, and β represents the difference in phase angle between the voltages at both ends; The behavior of a cable is defined by its length L, the series impedance per unit length Z and the shunt admittance Y: Divide the cable into n sections for evaluating internal voltage and current; According to the PUL parameters, the cable admittance matrix is ​​obtained: in, , ; Using the admittance matrix and the known terminal voltage, the current at the cable terminals can be calculated as: The cable active and reactive power transmitted from the offshore wind farm and absorbed by the onshore grid is calculated as follows: , ,in Pf arm is the active power of the cable in the offshore wind farm, Q fram is the cable reactive power of the offshore wind farm; , ,in P grid is the active power of the cable in the onshore electric field, Q grid is the cable reactive power of the onshore electric field.

2. The system according to claim 1, wherein: The target transformer includes a first target transformer and a second target transformer, and the transformer model includes: A classical approach simulation unit, configured to simulate a first target transformer based on a classical approach; The electromagnetic transient simulation unit is used for simulating the second target transformer based on electromagnetic transient.

3. The system according to claim 1, wherein: The cable model includes: A cable structure simulation unit, used for setting cable elements in the simulated cable; The parameter setting simulation unit is used to set relevant parameters of the cable element.

4. The system according to claim 3, characterized in that The cable structure simulation unit comprises: Conductor simulation subunit, used to determine the conductor and its material; an insulation layer simulation subunit, configured to construct an insulation layer outside the conductor; A metal sheath simulation subunit, used for providing a metal protective sheath located outside the insulating layer; The armor simulation subunit is used to set armor on the outside of the metal protective sleeve.

5. The system according to claim 3, wherein: The parameter setting simulation unit includes: a cable type simulation subunit, used to determine the type of transmission line; The parameter setting simulation subunit is used to set the relevant parameters of the cable.

6. The system according to claim 1, wherein: The wind power model includes: A wind source component simulation unit, used to determine the wind source components in the wind turbine; a mechanical generator set simulation unit, used for determining the mechanical generator set in the wind turbine; The speed regulator simulation unit is used to determine the speed regulator in the wind turbine.

7. The system according to claim 1, wherein: The simulation analysis module includes: Voltage loss analysis unit, used to determine the voltage loss of submarine cables under constant voltage conditions; A cable efficiency analysis unit is used to determine the cable efficiency of the submarine cable.

8. A constant voltage simulation method for wind power cables, characterized in that: include: Simulate the target transformer based on a preset path using a transformer model; Determine the cable components and their related parameters in the simulated cable through the cable model; Build wind turbines through wind power model simulation; Wherein, the cable model is connected to the transformer model and the wind power model; The wind power model includes: a simulation analysis module for determining the loss of submarine cables under constant pressure; The cable loss is ; Wherein, Ploss represents cable loss, Re{} represents the real part of the complex number, V1 represents the voltage of the offshore wind farm, V2 represents the voltage of the onshore power grid, I1 represents the current of the offshore wind farm, I2 represents the current of the onshore power grid, and * represents the conjugate operation of the complex number; Where V2=k·V grid , where V grid is the nominal voltage of the onshore power grid; V1: V1=V2·α·e jβ ; Where α is the ratio between the voltage amplitude on the onshore grid side and the grid section of the cable, and β represents the difference in phase angle between the voltages at both ends; The behavior of a cable is defined by its length L, the series impedance per unit length Z, and the shunt admittance Y: Divide the cable into n sections for evaluating internal voltage and current; According to the PUL parameters, the cable admittance matrix is ​​obtained: in, , ; Using the admittance matrix and the known terminal voltage, the current at the cable terminals can be calculated as: The cable active and reactive power transmitted from the offshore wind farm and absorbed by the onshore grid is calculated as follows: , ,in Pf arm is the active power of the cable in the offshore wind farm, Q fram is the cable reactive power of the offshore wind farm; , ,in P grid is the active power of the cable in the onshore electric field, Q grid is the cable reactive power of the onshore electric field.

9. The method according to claim 8, characterized in that The step of simulating the target transformer based on a preset approach using the transformer model includes: simulating a first target transformer based on a classical approach by a classical approach simulation unit; The second target transformer is simulated based on the electromagnetic transient simulation unit.

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