Steady-state cooperative control method for mixed embedded DC transmission system inter-type reactive power resources

Abstract

The present application relates to a kind of mixed embedded DC transmission system inter-type reactive resource steady-state collaborative control method, first, based on the steady-state voltage regulation requirement of conventional embedded DC bus, obtain the reactive-voltage sensitivity coefficient index of flexible and conventional embedded DC;Second, according to the reactive-voltage sensitivity coefficient index and the reference voltage value of conventional DC bus operation, obtain the reactive demand of conventional embedded DC voltage steady-state operation and the reactive adjustable amount of flexible converter station, and the type of reactive resource participating in voltage regulation is clear;If the type of reactive resource participating in voltage regulation is only flexible converter station, set the fixed reactive control conversion reference value input of flexible converter station;Otherwise, the reactive compensation device inside conventional embedded DC converter station needs to be switched.This application fully taps the potential of mixed embedded DC reactive resource, which helps to improve the efficiency and economy of mixed embedded DC transmission system voltage steady-state operation.

Description

Technical Field

[0001] This invention relates to a steady-state collaborative control method that considers multiple types of reactive resources among hybrid embedded DC transmission systems, belonging to the field of embedded DC control. Background Technology

[0002] Traditional power transmission systems primarily utilize AC transmission, but with the continuous development of DC transmission technology, DC transmission systems have gradually become an important alternative. Compared to AC transmission systems, DC transmission systems offer advantages such as lower current loss, better voltage control capabilities, and higher transmission capacity. Within DC transmission systems, embedded DC transmission systems, as a novel form of power transmission, are attracting increasing attention. In an AC power grid, an embedded DC transmission system mainly consists of a DC bus, converter stations, and connecting lines. Compared to traditional high-voltage DC transmission methods, it features lower voltage levels, shorter transmission distances, and a wider variety of converter station types. Due to these characteristics, embedded DC transmission systems possess greater reactive power regulation potential, potentially further improving the system's voltage steady-state operating efficiency and economy.

[0003] Currently, there are several challenges and difficulties in reactive power regulation for embedded DC systems. For example, effectively utilizing flexible regulation devices such as flexible converter stations, and coordinating control with reactive power compensation devices configured in conventional converter stations, are among the key issues that need to be addressed. Furthermore, due to the complexity and unique characteristics of embedded DC systems, traditional reactive power regulation methods often fall short of their requirements. Summary of the Invention

[0004] In order to solve the problems existing in the prior art, the present invention provides a steady-state collaborative control method to improve the efficiency and economy of steady-state voltage operation of hybrid embedded DC transmission systems.

[0005] To achieve the above objectives, the technical solution proposed in this invention is: a steady-state collaborative control method for multiple types of reactive power resources in a hybrid embedded DC transmission system.

[0006] Based on the steady-state voltage regulation requirements of conventional embedded DC converter bus, the reactive power-voltage sensitivity coefficient of flexible embedded DC converter station and conventional embedded DC converter station is obtained.

[0007] Based on the reactive power-voltage sensitivity coefficient and the reference voltage value of conventional embedded DC converter bus operation, the reactive power demand of conventional embedded DC voltage steady-state operation and the reactive power adjustable amount of flexible embedded DC converter station are obtained, and the types of reactive power resources participating in voltage regulation are identified.

[0008] If the reactive power adjustable amount of the flexible embedded DC converter station meets the reactive power demand for steady-state operation, then the reactive power resource type participating in voltage regulation is only the flexible embedded DC converter station. The reactive power reference value for the constant reactive power control of the flexible converter station is set according to the reference voltage value and the steady-state voltage regulation requirements.

[0009] If the reactive power adjustable amount of the flexible embedded DC converter station does not meet the reactive power demand for steady-state operation, the reactive power resource type participating in voltage regulation also needs to switch on the reactive power compensation device inside the conventional embedded DC converter station, calculate the reactive power correction adjustment amount of the flexible converter station after the reactive power compensation device is put on, and then set the corrected reactive power reference value for the constant reactive power control of the flexible converter station.

[0010] A further design of the above technical solution is as follows: Based on the steady-state voltage regulation requirements of conventional embedded DC converter buses, the method for obtaining the reactive power-voltage sensitivity coefficient index of conventional embedded DC converter stations is as follows:

[0011]

[0012] In the formula: S LCC The reactive-voltage sensitivity coefficient is a standard embedded DC power supply parameter; m represents the total number of times inductive reactive loads of different capacities are applied at the converter bus; ΔQ LCCi To apply the i-th inductive reactive load; ΔU Lpcci This represents the voltage change on the converter bus caused by the first inductive reactive load being applied.

[0013] The method for obtaining the reactive power-voltage sensitivity coefficient of a flexible embedded DC converter station is as follows:

[0014]

[0015] In the formula S MMCj ΔQ represents the reactive power-voltage sensitivity coefficient of the j-th flexible converter station; m represents the total number of times inductive reactive loads of different capacities are connected at the j-th converter bus; ΔQ LCCi To apply the i-th inductive reactive load at the j-th converter bus; ΔU Mpcci Let be the voltage change of the converter bus caused by the i-th inductive reactive load being applied at the j-th converter bus.

[0016] The method for obtaining the reactive power demand of conventional embedded DC voltage steady-state operation based on the conventional embedded DC reactive power-voltage sensitivity coefficient index and the reference voltage value of conventional embedded DC converter bus operation is as follows:

[0017] ΔQ LCC =S LCC *(U LCC_ref -ULCC )

[0018] Where: ΔQ LCC This represents the reactive power demand for steady-state DC operation; S LCC U represents the reactive power-voltage sensitivity coefficient of a conventional embedded DC converter; m represents the total number of times inductive reactive loads of different capacities are applied at the converter bus; U LCC_ref This is the reference value for the voltage of a conventional embedded DC converter bus; U LCC This is the real-time data of the converter bus voltage of a conventional embedded DC converter.

[0019] The method for calculating the reactive power adjustable capacity of the flexible converter station is as follows:

[0020]

[0021] Where: ΔQ MMC_sum For the reactive power regulation of all flexible converter stations; ΔQ MMCi_max ΔQ represents the maximum reactive power output of the i-th flexible converter station. MMCi represents the real-time reactive power output data of the i-th flexible converter station; N represents the total number of flexible converter stations in the embedded flexible DC transmission system.

[0022] Based on the relationship between the reactive power demand of conventional embedded DC power supply under steady-state voltage operation and the reactive power regulation of flexible embedded DC converter stations, the types of reactive power resources involved in voltage regulation are identified. The specific discrimination expression is as follows:

[0023] ΔQ MMC_sum ≥ΔQ LCC

[0024] Where: ΔQ MMC_sum For the reactive power regulation of all flexible converter stations; ΔQ LCC This represents the reactive power demand for steady-state DC voltage operation.

[0025] If the above formula holds true, then only the flexible embedded DC converter station needs to participate in the converter bus voltage regulation; otherwise, the reactive power compensation device inside the conventional embedded DC converter station needs to be switched on or off.

[0026] If the reactive power resource type involved in voltage regulation is only the flexible embedded DC converter station, the reactive power control of the flexible converter station in the flexible embedded DC system will be switched to constant reactive power control mode, and the assignment weight of each flexible converter station will be designed according to the real-time reactive power margin of each flexible converter station:

[0027]

[0028] In the formula, k i ΔQ is the weighting coefficient for the reactive power margin of the i-th flexible converter station. MMC_sumFor the reactive power regulation of all flexible converter stations; Q MMCi_max Q represents the maximum reactive power output of the i-th flexible converter station. MMCi This provides the real-time reactive power output data for the i-th flexible converter station.

[0029] The reactive power reference value for the constant reactive power control mode is:

[0030] Q MMCi_ref =k i *ΔQ LCC

[0031] In the formula, Q MMCi_ref Let k be the reactive power reference value for the reactive power control mode of the i-th flexible converter station; i ΔQ is the weighting coefficient for the reactive power margin of the i-th flexible converter station. LCC This represents the reactive power demand for steady-state DC operation.

[0032] If a reactive power compensation device is required in a conventional embedded DC system converter station, then the reactive power compensation device that is closest to the reactive power demand of the conventional embedded DC system under steady-state voltage operation should be selected for implementation.

[0033] After the reactive power compensation device is activated, the reactive power correction adjustment amount of the flexible embedded DC converter station is:

[0034] ΔQ' MMC =|ΔQ LCC -ΔQ BC |

[0035] In the formula, ΔQ' MMC The reactive power correction adjustment for the flexible converter station; ΔQ LCC This represents the reactive power demand for steady-state DC operation; ΔQ BC The capacity for energizing reactive power compensation devices;

[0036] The reactive power reference values ​​for the constant reactive power control mode of each flexible converter station are assigned as follows:

[0037] Q' MMCi_ref =k i *ΔQ' MMC

[0038] In the formula, ΔQ' MMCi_ref Here is the corrected reactive power reference value for the i-th flexible converter station; k i ΔQ' is the weighting coefficient for the reactive power margin of the i-th flexible converter station. MMC This is the reactive power correction adjustment amount for flexible converter stations.

[0039] An electronic device includes a memory, a processor, and a computer program, the computer program being stored in the memory and configured to be executed by the processor to implement the above-described steady-state coordinated control method for multiple types of reactive power resources in a hybrid embedded DC transmission system.

[0040] A computer-readable storage medium storing a computer program, wherein the computer program, when executed, controls the device containing the computer-readable storage medium to perform the aforementioned steady-state coordinated control method for multiple types of reactive power resources in a hybrid embedded DC transmission system.

[0041] The beneficial effects of this invention are as follows:

[0042] This invention addresses the steady-state coordinated control problem of multiple types of reactive power resources in hybrid embedded DC transmission systems. It proposes a method considering the steady-state coordinated control of various reactive power resources within the hybrid embedded DC transmission system. Based on the decoupling control of active and reactive power in the converter station of the flexible embedded DC transmission system and its continuous real-time response characteristics, the method can perform real-time tracking control of the voltage at the converter bus of the conventional embedded DC transmission system during steady-state operation. Simultaneously, the converter station of the flexible embedded DC transmission system can also smooth out voltage fluctuations generated during the switching of discrete reactive power compensation devices configured in the converter station of the conventional embedded DC transmission system. The proposed method fully exploits the potential of various reactive power resources in existing hybrid embedded DC transmission systems without increasing investment in other electrical equipment. This helps improve the efficiency and economy of steady-state voltage operation of hybrid embedded DC transmission systems, and has significant practical significance and application value. It provides a reference for power system planners and dispatchers in the planning, design, and operation scheme formulation of power grids containing hybrid embedded DC transmission systems. Attached Figure Description

[0043] Figure 1 This is a flowchart of the steps of a steady-state collaborative control method for multiple types of reactive resources in a hybrid embedded DC transmission system according to the present invention.

[0044] Figure 2 This is a schematic diagram of the topology of the hybrid embedded DC transmission system of the present invention;

[0045] Figure 3 This is a schematic diagram of the flexible embedded DC constant reactive power control circuit of the present invention. Detailed Implementation

[0046] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0047] Example 1

[0048] This embodiment presents a steady-state collaborative control method for multiple types of reactive power resources in a hybrid embedded DC transmission system, such as... Figure 1 As shown, the specific steps include the following:

[0049] Step 1: Based on the steady-state voltage regulation requirements of conventional embedded DC converter bus, the reactive power-voltage sensitivity coefficient of flexible embedded DC converter station and conventional embedded DC converter station is obtained by simulation experiment.

[0050] Specifically as follows:

[0051] Taking hybrid embedded DC transmission systems as the research object, such as Figure 2 As shown, based on the steady-state voltage regulation requirements of a conventional embedded DC converter bus, a simulation experiment is used to obtain the reactive power-voltage sensitivity coefficient of the conventional embedded DC converter bus. The method involves applying inductive reactive loads of different capacities to the converter bus during steady-state operation and collecting the voltage changes of the conventional embedded DC converter bus under different capacities. The formula for calculating the reactive power-voltage sensitivity coefficient of the conventional embedded DC converter bus can then be obtained.

[0052]

[0053] In the formula, S LCC The reactive-voltage sensitivity coefficient is a standard embedded DC power supply parameter; m represents the total number of times inductive reactive loads of different capacities are applied at the converter bus; ΔQ LCCi To apply the i-th inductive reactive load; ΔU Lpcci This represents the voltage change on the converter bus caused by the first inductive reactive load being applied.

[0054] Similar to the reactive power-voltage sensitivity coefficient of embedded DC, the reactive power-voltage sensitivity coefficient of flexible embedded DC is obtained through simulation experiments. During steady-state operation, inductive reactive loads of different capacities are applied to the converter bus, and the voltage changes of the flexible embedded DC converter bus under different capacities are collected. The formula for calculating the reactive power-voltage sensitivity coefficient of the j-th flexible converter station can then be obtained.

[0055]

[0056] In the formula, S MMCj ΔQ represents the reactive power-voltage sensitivity coefficient of the j-th flexible converter station; m represents the total number of times inductive reactive loads of different capacities are connected at the j-th converter bus; ΔQ LCCi To apply the i-th inductive reactive load at the j-th converter bus; ΔU Mpcci Let be the voltage change of the converter bus caused by the i-th inductive reactive load being applied at the j-th converter bus.

[0057] Step 2: Based on the reactive power-voltage sensitivity coefficient index and the reference voltage value of conventional DC converter bus operation, obtain the reactive power demand for conventional embedded DC voltage steady-state operation and the reactive power adjustable quantity of flexible converter station, and identify the types of reactive power resources involved in voltage regulation.

[0058] Specifically as follows:

[0059] Real-time converter bus voltage data of a conventional embedded DC converter are collected. Based on the reactive power-voltage sensitivity coefficient calculation formula of the conventional embedded DC converter, the reactive power demand of the conventional embedded DC converter under steady-state voltage operation is obtained.

[0060] ΔQ LCC =S LCC *(U LCC_ref -U LCC )

[0061] In the formula ΔQ LCC This represents the reactive power demand for steady-state DC operation; S LCC U represents the reactive power-voltage sensitivity coefficient of a conventional embedded DC converter; m represents the total number of times inductive reactive loads of different capacities are applied at the converter bus; U LCC_ref This is the reference value for the conventional DC converter bus voltage; U LCC To collect real-time data of the converter bus voltage of a conventional embedded DC converter.

[0062] Taking into account the reactive power output limits of each flexible converter station and combining the real-time reactive power output data of the flexible converter stations, the reactive power adjustable quantity of all flexible converter stations in the flexible embedded DC system is quantified:

[0063]

[0064] In the formula ΔQ MMC_sum For the reactive power regulation of all flexible converter stations; ΔQ MMCi_max ΔQ represents the maximum reactive power output of the i-th flexible converter station. MMCi represents the real-time reactive power output data of the i-th flexible converter station; N represents the total number of flexible converter stations in the embedded flexible DC transmission system.

[0065] Based on the relationship between the reactive power demand of conventional embedded DC voltage steady-state operation and the reactive power regulation of all flexible converter stations in the flexible embedded DC system, the types of reactive power resources participating in voltage regulation are identified, and the discrimination expression is as follows:

[0066] ΔQ MMC_sum ≥ΔQ LCC

[0067] In the formula ΔQ MMC_sum For the reactive power regulation of all flexible converter stations; ΔQ LCCThis represents the reactive power demand for steady-state DC operation.

[0068] If the above formula holds true, only the flexible converter station needs to participate in the converter bus voltage regulation. Otherwise, it is necessary to switch on and off the reactive power compensation device inside the conventional embedded DC converter station.

[0069] Step 3: If the reactive power resource type involved in voltage regulation is only the flexible converter station, set the input of the reactive power control converter reference value for the flexible converter station based on the comprehensive reference voltage value and steady-state voltage regulation requirements.

[0070] Specifically as follows:

[0071] If the reactive power resource type involved in voltage regulation is only flexible converter stations, the reactive power control of the flexible converter stations in the flexible embedded DC system is switched to constant reactive power control mode, and the assignment weights of each flexible converter station are designed according to the real-time reactive power margin of each flexible converter station:

[0072]

[0073] In the formula k i ΔQ is the weighting coefficient for the reactive power margin of the i-th flexible converter station. MMC_sum For the reactive power regulation of all flexible converter stations; Q MMCi_max Q represents the maximum reactive power output of the i-th flexible converter station. MMCi This represents the real-time reactive power output data for the i-th flexible converter station.

[0074] If the reactive power resource type involved in voltage regulation is only the flexible converter station, the reactive power control of the flexible converter station in the flexible embedded DC system switches to constant reactive power control mode. Its control loop diagram is shown below. Figure 3 As shown, the expression for the reactive power reference value in the constant reactive power control mode is:

[0075] Q MMCi_ref =k i *ΔQ LCC

[0076] In the formula Q MMCi_ref Let k be the reactive power reference value for the reactive power control mode of the i-th flexible converter station; i ΔQ is the weighting coefficient for the reactive power margin of the i-th flexible converter station. LCC This represents the reactive power demand for steady-state DC operation.

[0077] Step 4: If the reactive power adjustable amount of the flexible embedded DC converter station does not meet the reactive power demand for steady-state operation, the reactive power resource type participating in voltage regulation also needs to switch the reactive power compensation device inside the conventional embedded DC converter station, calculate the reactive power correction adjustment amount of the flexible converter station after the reactive power compensation device is put into operation, and then set the corrected reactive power reference value for the constant reactive power control of the flexible converter station.

[0078] Specifically as follows:

[0079] Based on the determined type of reactive power resources involved in voltage regulation, if it is necessary to put reactive power compensation devices into the converter station of a conventional embedded DC system, since the capacity of reactive power compensation devices in the converter station varies, the reactive power compensation device that is closest to the reactive power demand of the conventional DC voltage steady-state operation should be selected for implementation.

[0080] After the reactive power compensation device is put into operation, it will cause significant voltage fluctuations. The converter bus voltage is difficult to maintain directly at the voltage reference value, and a flexible converter station is required to correct and adjust it. The expression for the reactive power correction adjustment amount is:

[0081] ΔQ' MMC =|ΔQ LCC -ΔQ BC |

[0082] In the formula ΔQ' MMC The reactive power correction adjustment for the flexible converter station; ΔQ LCC This represents the reactive power demand for steady-state DC operation; ΔQ BC The capacity for energizing reactive power compensation devices;

[0083] At this point, the reactive power control mode of the flexible converter station switches to constant reactive power control. Based on the calculated reactive power margin weighting coefficient of the flexible converter station, the reactive power reference value of the constant reactive power control mode for each flexible converter station can be assigned, and its expression is:

[0084] Q' MMCi_ref =k i *ΔQ' MMC

[0085] In the formula ΔQ' MMCi_ref Here is the corrected reactive power reference value for the i-th flexible converter station; k i ΔQ' is the weighting coefficient for the reactive power margin of the i-th flexible converter station. MMC This is the reactive power correction adjustment amount for flexible converter stations.

[0086] Example 2

[0087] This embodiment provides an electronic device, including a memory, a processor, and a computer program. The computer program is stored in the memory and configured to be executed by the processor to implement the steady-state coordinated control method for multiple types of reactive power resources in a hybrid embedded DC transmission system according to Embodiment 1.

[0088] Example 3

[0089] This embodiment also provides a computer-readable storage medium storing a computer program. When the computer program runs, it controls the device where the computer-readable storage medium is located to execute the steady-state coordinated control method for multiple types of reactive power resources in the hybrid embedded DC transmission system of Embodiment 1.

[0090] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can 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.) containing computer-usable program code. The solutions in the embodiments of this application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0091] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0092] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0093] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0094] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0095] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

[0096] The technical solutions of the present invention are not limited to the above embodiments. All technical solutions obtained by equivalent substitution fall within the scope of protection claimed by the present invention.

Claims

1. A steady-state coordinated control method for multiple types of reactive power resources in a hybrid embedded DC transmission system, characterized in that: Based on the steady-state voltage regulation requirements of conventional embedded DC converter bus, the reactive power-voltage sensitivity coefficient of flexible embedded DC converter station and conventional embedded DC converter station is obtained. Based on the reactive power-voltage sensitivity coefficient and the reference voltage value of conventional embedded DC converter bus operation, the reactive power demand of conventional embedded DC voltage steady-state operation and the reactive power adjustable amount of flexible embedded DC converter station are obtained, and the types of reactive power resources participating in voltage regulation are identified. If the reactive power adjustable amount of the flexible embedded DC converter station meets the reactive power demand for steady-state operation, then the reactive power resource type participating in voltage regulation is only the flexible embedded DC converter station. The reactive power reference value for the constant reactive power control of the flexible converter station is set according to the reference voltage value and the steady-state voltage regulation requirements. If the reactive power adjustable amount of the flexible embedded DC converter station does not meet the reactive power demand for steady-state operation, the reactive power resource type participating in voltage regulation also needs to switch on the reactive power compensation device inside the conventional embedded DC converter station, calculate the reactive power correction adjustment amount of the flexible converter station after the reactive power compensation device is put on, and then set the corrected reactive power reference value for the constant reactive power control of the flexible converter station.

2. The steady-state coordinated control method for multiple types of reactive power resources in a hybrid embedded DC transmission system according to claim 1, characterized in that: Based on the steady-state voltage regulation requirements of conventional embedded DC converter buses, the method for obtaining the reactive power-voltage sensitivity coefficient of conventional embedded DC converter stations is as follows: In the formula: S LCC The reactive-voltage sensitivity coefficient is a standard embedded DC power supply parameter; m represents the total number of times inductive reactive loads of different capacities are applied at the converter bus; ΔQ LCCi To apply the i-th inductive reactive load; ΔU Lpcci This represents the voltage change on the converter bus caused by the first inductive reactive load being applied.

3. The steady-state coordinated control method for multiple types of reactive power resources in a hybrid embedded DC transmission system according to claim 2, characterized in that: The method for obtaining the reactive power-voltage sensitivity coefficient of a flexible embedded DC converter station is as follows: In the formula S MMCj ΔQ represents the reactive power-voltage sensitivity coefficient of the j-th flexible converter station; m represents the total number of times inductive reactive loads of different capacities are connected at the j-th converter bus; ΔQ LCCi To apply the i-th inductive reactive load at the j-th converter bus; ΔU Mpcci Let be the voltage change of the converter bus caused by the i-th inductive reactive load being applied at the j-th converter bus.

4. The steady-state coordinated control method for multiple types of reactive power resources in a hybrid embedded DC transmission system according to claim 3, characterized in that: The method for obtaining the reactive power demand of conventional embedded DC voltage steady-state operation based on the conventional embedded DC reactive power-voltage sensitivity coefficient index and the reference voltage value of conventional embedded DC converter bus operation is as follows: ΔQ LCC =S LCC *(U LCC_ref -U LCC ) Where: ΔQ LCC This represents the reactive power demand for steady-state DC operation; S LCC U represents the reactive power-voltage sensitivity coefficient of a conventional embedded DC converter; m represents the total number of times inductive reactive loads of different capacities are applied at the converter bus; U LCC_ref This is the reference value for the voltage of a conventional embedded DC converter bus; U LCC This is the real-time data of the converter bus voltage of a conventional embedded DC converter.

5. The steady-state coordinated control method for multiple types of reactive power resources in a hybrid embedded DC transmission system according to claim 4, characterized in that: The method for calculating the reactive power adjustable capacity of the flexible converter station is as follows: Where: ΔQ MMC_sum For the reactive power regulation of all flexible converter stations; ΔQ MMCi_max ΔQ represents the maximum reactive power output of the i-th flexible converter station. MMCi represents the real-time reactive power output data of the i-th flexible converter station; N represents the total number of flexible converter stations in the embedded flexible DC transmission system.

6. The steady-state coordinated control method for multiple types of reactive power resources in a hybrid embedded DC transmission system according to claim 5, characterized in that: Based on the relationship between the reactive power demand of conventional embedded DC power supply under steady-state voltage operation and the reactive power regulation of flexible embedded DC converter stations, the types of reactive power resources involved in voltage regulation are identified. The specific discrimination expression is as follows: ΔQ MMC_sum ≥ΔQ LCC Where: ΔQ MMC_sum For the reactive power regulation of all flexible converter stations; ΔQ LCC This represents the reactive power demand for steady-state DC voltage operation. If the above formula holds true, then only the flexible embedded DC converter station needs to participate in the converter bus voltage regulation; otherwise, the reactive power compensation device inside the conventional embedded DC converter station needs to be switched on or off.

7. The steady-state coordinated control method for multiple types of reactive power resources in a hybrid embedded DC transmission system according to claim 6, characterized in that: If the reactive power resource type involved in voltage regulation is only the flexible embedded DC converter station, the reactive power control of the flexible converter station in the flexible embedded DC system will be switched to constant reactive power control mode, and the assignment weight of each flexible converter station will be designed according to the real-time reactive power margin of each flexible converter station: In the formula, k i ΔQ is the weighting coefficient for the reactive power margin of the i-th flexible converter station. MMC_sum For the reactive power regulation of all flexible converter stations; Q MMCi_max Q represents the maximum reactive power output of the i-th flexible converter station. MMCi This provides the real-time reactive power output data for the i-th flexible converter station. The reactive power reference value for the constant reactive power control mode is: Q MMCi_ref =k i *ΔQ LCC In the formula, Q MMCi_ref Let k be the reactive power reference value for the reactive power control mode of the i-th flexible converter station; i ΔQ is the weighting coefficient for the reactive power margin of the i-th flexible converter station. LCC This represents the reactive power demand for steady-state DC operation.

8. The steady-state coordinated control method for multiple types of reactive power resources in a hybrid embedded DC transmission system according to claim 7, characterized in that: If a reactive power compensation device is required in a conventional embedded DC system converter station, then the reactive power compensation device that is closest to the reactive power demand of the conventional embedded DC system under steady-state voltage operation should be selected for implementation. After the reactive power compensation device is activated, the reactive power correction adjustment amount of the flexible embedded DC converter station is: ΔQ' MMC =|ΔQ LCC -ΔQ BC | In the formula, ΔQ' MMC The reactive power correction adjustment for the flexible converter station; ΔQ LCC This represents the reactive power demand for steady-state DC operation; ΔQ BC The capacity for energizing reactive power compensation devices; The reactive power reference values ​​for the constant reactive power control mode of each flexible converter station are assigned as follows: Q' MMCi_ref =k i *ΔQ' MMC In the formula, ΔQ' MMCi_ref Here is the corrected reactive power reference value for the i-th flexible converter station; k i ΔQ' is the weighting coefficient for the reactive power margin of the i-th flexible converter station. MMC This is the reactive power correction adjustment amount for flexible converter stations.

9. An electronic device, characterized in that: The system includes a memory, a processor, and a computer program, the computer program being stored in the memory and configured to be executed by the processor to implement the steady-state coordinated control method for multiple types of reactive power resources in a hybrid embedded DC transmission system as described in any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, which, when executed, controls the device containing the computer-readable storage medium to perform the steady-state coordinated control method for multiple types of reactive power resources in a hybrid embedded DC transmission system as described in any one of claims 1 to 8.

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