Electric power stability control method and system for wide-area alternating-current and direct-current hybrid electric power system

Abstract

The invention relates to the technical field of power grid safety and stability control, in particular to a power stability control method and system for a wide-area alternating-current and direct-current hybrid power system. Through cooperative control of an alternating current power grid, conventional extra-high voltage direct current transmission and multi-end flexible direct current transmission in the wide-area alternating current and direct current hybrid power system, when the alternating current system power grid has a serious fault and active unbalance, the multi-end flexible direct current power is adjusted preferentially, a sending end alternating current power supply is cut off at the secondary stage, and the conventional extra-high voltage direct current transmission power is adjusted in an auxiliary manner; rapid power transfer distribution and dynamic balance are realized, the power grid fault response speed and regulation and control precision are improved, the total generator tripping amount of a sending-end alternating current system is remarkably reduced, the low-frequency operation risk of the power grid is effectively reduced, and the depth and frequency of multi-loop extra-high voltage direct current cooperation participating in loop reduction of output direct current power are reduced. And the optimal scheduling and utilization of power supply and power grid resources are realized on the premise of ensuring the safety and stability of the whole network system.

Description

Technical Field

[0001] This invention relates to the field of power grid safety and stability control technology, and in particular to a power stability control method and system for wide-area AC / DC hybrid power systems. Background Technology

[0002] During power grid operation, various faults and disturbances of varying degrees will occur. To address the operational risks of the power grid under the N-2 fault mode and ensure its safe and stable operation (including transient stability and thermal stability), the entire network system is equipped with various AC / DC power grid safety and stability control systems (referred to as stability control systems) on important AC / DC transmission channels. These stability control systems operate independently yet collaboratively, implementing corresponding stability control measures (referred to as stability control measures). The multiple AC / DC power grid safety and stability control systems configured within the power grid are divided into three main categories: multiple AC stability control systems, multiple conventional UHVDC stability control systems / multi-terminal flexible DC stability control systems, and AC / DC coordinated stability control systems. Among these, the AC / DC coordinated stability control system represents the highest level of stability control for the entire power grid.

[0003] Currently, while meeting the needs of more hydropower and new energy sources for external transmission, under severe fault conditions in some main power grids (grid N-2), in order to maintain the stability of the entire grid system (transient stability and thermal stability), the current AC / DC stability control system adopts the following stability control strategies: 1) The AC stability control system adopts a stability control measure of cutting off a large number of power generation units (hydropower and new energy grid connection lines) on the sending side. However, excessive power generation cut-off may cause the grid to face a low-frequency instability risk; 2) If the total number of power generation units cut off on the sending side exceeds a certain threshold, multiple UHVDC stability control systems need to take measures to reduce DC power. However, this measure will affect the operational stability of the UHVDC system.

[0004] How to meet the future demand for large-capacity new energy power transmission while simultaneously addressing the risks faced under severe AC / DC grid fault conditions is a key technical issue that needs to be considered and urgently resolved in grid planning.

[0005] How to improve and optimize the stability control strategies and methods of multi-type and multi-level AC / DC stability control systems across the entire network, based on the inherent technical advantages of multi-terminal flexible DC systems and the characteristics of power grid operation, is a crucial technical issue for solving the current and future power grid operation risks and promoting the wider application and technological development of flexible DC transmission systems in various power scenarios. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a power stabilization and control method for a wide-area AC / DC hybrid power system, characterized by comprising the following steps:

[0007] S1. By acquiring multi-source data, obtain real-time operation data of AC power grid, conventional UHVDC power grid and multi-terminal flexible DC power grid within the wide-area AC / DC hybrid power system, and construct a real-time power grid operation data matrix;

[0008] S2. Calculate the DC adjustable power regulation margin data of the multi-terminal flexible DC grid based on the real-time operation data matrix of the power grid. ;

[0009] S3. When an N-2 or higher fault occurs in the AC transmission channel of a power source in a wide-area AC / DC hybrid power system, the total number of power source trips in the AC power grid is calculated based on the pre-set AC grid stability control strategy and the real-time grid operation data matrix. Data on the total number of power supply trips. With preset start-up threshold data for wide-area AC / DC hybrid power systems Perform data size judgment: when Data less than the gate valve threshold Then, based on the total number of power supply trips... Disconnect the power supply from the AC mains; otherwise, proceed to step S4.

[0010] S4. Data on the adjustment margin of multi-terminal flexible DC adjustable power Total power supply switching data Perform data size determination:

[0011] When the margin data Greater than the total number of power supply trips At the same time, based on the pre-set stability control strategy, the adjustable DC power value of the multi-terminal flexible DC grid is increased. ;

[0012] When the margin data Less than or equal to the total number of power supply trips At the same time, based on the pre-set stability control strategy, the adjustable DC power value of the multi-terminal flexible DC grid is increased. And based on the improved multi-terminal flexible DC adjustable power value The total number of second power source trips in the AC power grid was calculated. ;

[0013] S5. Total data on the second power supply tripping. Valve threshold data Perform data size determination:

[0014] When the total data of the second power supply switching Data less than the gate valve threshold Then, based on the total number of power supply trips... Disconnect the power source from the AC power grid;

[0015] When the second power supply is switched off in total Data greater than or equal to the valve threshold data Then, based on the total number of power supply trips... Disconnect power sources from the AC power grid and reduce the DC power output of the conventional UHVDC power grid. .

[0016] Based on the above method, the present invention also provides a power stability control system for a wide-area AC / DC hybrid power system. The system is implemented based on any one of the above power stability control methods for a wide-area AC / DC hybrid power system, including a multi-source data acquisition subsystem, which is used to acquire real-time operating data of the AC power grid, conventional UHVDC power grid and multi-terminal flexible DC power grid within the wide-area AC / DC hybrid power system through multi-source data acquisition, and construct a real-time power grid operating data matrix.

[0017] The AC stability control subsystem is used to calculate the total number of AC power generation trips based on the pre-set stability control strategy and the real-time operation data matrix of the power grid when N-2 or more faults occur in the AC power transmission channel of the wide-area AC-DC hybrid power system.

[0018] The multi-terminal flexible DC stabilization subsystem is used to calculate the DC adjustable power regulation margin data of the multi-terminal flexible DC grid based on the real-time operation data matrix of the power grid.

[0019] The AC / DC coordinated safety and stability control subsystem is used to make data judgments based on the total power supply tripping data, DC adjustable power adjustment margin data, and the start-up valve threshold data of the conventional UHVDC grid, and transmit stability control execution commands to the AC stability control subsystem, the multi-terminal flexible DC stability control subsystem, and the DC stability control subsystem respectively according to the judgment results.

[0020] The UHVDC stabilization subsystem is used to perform power reduction operations on the UHVDC power grid according to the stabilization execution command.

[0021] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement a power stabilization method for a wide-area AC / DC hybrid power system as described above.

[0022] A storage medium storing a computer program thereon, which, when executed by a processor, implements a power stabilization and control method for a wide-area AC / DC hybrid power system as described above.

[0023] The beneficial effects of this invention are that, through the coordinated control of the AC grid, conventional UHVDC transmission, and multi-terminal flexible DC transmission in a wide-area AC / DC hybrid power system, when a severe fault (grid N-2) or power imbalance occurs in the AC system grid, the invention prioritizes adjusting the power of the multi-terminal flexible DC transmission, then cuts off the sending-end AC power supply, and assists in adjusting the power of the conventional UHVDC transmission. This achieves rapid power transfer and dynamic balance, improves the grid's fault response speed and control accuracy, thereby enhancing the grid's ability to withstand severe fault risks and effectively reducing the risk of low-frequency grid operation. Simultaneously, based on the technical aspects of the stability control strategy method in a multi-type, multi-level AC / DC stability control system across the entire grid, and considering the inherent technical advantages of the multi-terminal flexible DC system and the characteristics of grid operation, the invention effectively improves the transient stability performance and overall stability level of the entire grid system. It significantly reduces the total number of generators cut off from the sending-end AC system, thereby reducing the risk of low-frequency operation across the entire grid while also reducing the depth and frequency of multiple UHVDC transmissions cooperating to reduce the output DC power, improving the overall safety, stability, and flexibility of the system. This achieves optimal scheduling and utilization of power and grid resources while ensuring the safety and stability of the entire grid system. Attached Figure Description

[0024] Figure 1 This is a schematic flowchart of a power stabilization and control method for a wide-area AC / DC hybrid power system according to an embodiment of the present invention.

[0025] Figure 2 This is a schematic diagram of the structure of a power stabilization and control system for a wide-area AC / DC hybrid power system according to an embodiment of the present invention.

[0026] Figure 3 This is a schematic diagram of a power stability control judgment logic for a wide-area AC / DC hybrid power system according to an embodiment of the present invention.

[0027] Figure 4 This is a schematic diagram of the terminal equipment structure of a power stabilization and control method for a wide-area AC / DC hybrid power system according to an embodiment of the present invention.

[0028] Figure 5 This is a schematic diagram of a computer-readable storage medium structure for a power stabilization and control method in a wide-area AC / DC hybrid power system, according to an embodiment of the present invention.

[0029] In the diagram, 200 is the terminal device, 210 is the memory, 211 is the RAM, 212 is the cache memory, 213 is the ROM, 214 is the program / utility, 215 is the program module, 220 is the processor, 230 is the bus, 240 is the external device, 250 is the I / O interface, 260 is the network adapter, and 300 is the program product. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention; that is, the described embodiments are only a part of the embodiments of the invention, and not all of them. The components of the embodiments of the invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0031] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention. It should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0032] Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or machine that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or machine. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or machine that includes said element.

[0033] Example 1:

[0034] like Figure 1 As shown, Embodiment 1 of the present invention provides a power stabilization and control method for a wide-area AC / DC hybrid power system, comprising the following steps:

[0035] S1. By acquiring multi-source data, obtain real-time operation data of AC power grid, conventional UHVDC power grid and multi-terminal flexible DC power grid within the wide-area AC / DC hybrid power system, and construct a real-time power grid operation data matrix;

[0036] S2. Calculate the DC adjustable power regulation margin data of the multi-terminal flexible DC grid based on the real-time operation data matrix of the power grid. ;

[0037] S3. When an N-2 or higher fault occurs in the AC transmission channel of a power source in a wide-area AC / DC hybrid power system, the total number of power source trips in the AC power grid is calculated based on the pre-set AC grid stability control strategy and the real-time grid operation data matrix. Data on the total number of power supply trips. With preset start-up threshold data for wide-area AC / DC hybrid power systems Perform data size judgment: when Data less than the gate valve threshold Then, based on the total number of power supply trips... Disconnect the power supply from the AC mains; otherwise, proceed to step S4.

[0038] S4. Data on the adjustment margin of multi-terminal flexible DC adjustable power Total power supply switching data Perform data size determination:

[0039] When the margin data Greater than the total number of power supply trips At the same time, based on the pre-set stability control strategy, the adjustable DC power value of the multi-terminal flexible DC grid is increased. ;

[0040] When the margin data Less than or equal to the total number of power supply trips At the same time, based on the pre-set stability control strategy, the adjustable DC power value of the multi-terminal flexible DC grid is increased. And based on the improved multi-terminal flexible DC adjustable power value The total number of second power source trips in the AC power grid was calculated. ;

[0041] S5. Total data on the second power supply tripping. Valve threshold data Perform data size determination:

[0042] When the total data of the second power supply switching Data less than the gate valve threshold Then, based on the total number of power supply trips... Disconnect the power source from the AC power grid;

[0043] When the second power supply is switched off in total Data greater than or equal to the valve threshold data Then, based on the total number of power supply trips... Disconnect power sources from the AC power grid and reduce the DC power output of the conventional UHVDC power grid. .

[0044] Furthermore, the real-time operating data includes generator power angle data, AC grid voltage data, AC grid power data, AC grid frequency data, AC grid generator speed data, DC power data and DC voltage data of conventional UHVDC grids and multi-terminal flexible DC grids, etc.

[0045] Furthermore, the stabilization strategy includes disconnecting hydropower units on the power supply side, disconnecting new energy grid-connected lines on the power supply side, and modulating multi-terminal flexible DC power and multi-circuit ultra-high voltage DC power.

[0046] Furthermore, in step S2, based on the real-time operating data of the converter stations and DC grid at the sending and receiving ends of the multi-terminal flexible DC grid, it is calculated whether there is DC adjustable power margin data that meets the safety requirements of flexible DC grid during the current time period. .

[0047] Furthermore, in step S3, when an N-2 severe fault occurs in the AC power transmission channel of the wide-area AC / DC hybrid power system, the power generation units in the AC grid are disconnected according to the preset stability control strategy, and the total number of disconnected power generation units is determined. Valve threshold data Is the data size relationship... If so, proceed to step S4.

[0048] Specifically, the implementation process of each step in the above embodiments is as follows:

[0049] Step 1: In a wide-area complex AC / DC hybrid power system containing both multi-terminal flexible DC and conventional UHVDC, three major types of power grid safety and stability control systems (referred to as stability control systems) are configured to ensure the safe operation of the entire power grid. Each stability control system, based on its structural attributes, functional positioning, and technical requirements, collects, monitors, summarizes, and uploads real-time signal information regarding the operating conditions of its respective power grid, or issues and executes commands.

[0050] Step 2-A: In a multi-terminal flexible DC transmission stability control system where both the sending and receiving end converter stations are connected to the synchronous AC grid, the system calculates, analyzes, and confirms, based on the real-time power operation conditions of the sending and receiving end converter stations and DC transmission lines, whether the multi-terminal flexible DC transmission system has a DC adjustable power margin that meets the safety requirements of flexible DC transmission, and the magnitude of such margin. .

[0051] Step 2-B: If a severe N-2 fault occurs on a 500kV or higher main line of a major power transmission channel, the AC stability control system shall, according to the stability control strategy table, disconnect a certain capacity of power generating units on the sending end side. Stability control measures; determining the total amount of power to be cut off. (A threshold value for uploading certain startup information to the AC / DC co-control system).

[0052] Specifically, regarding the threshold data for starting the valve. And settings. Power systems, which contain numerous power components (generators, transformers, AC / DC transmission lines, motors, power electronic equipment components, etc.), will encounter various disturbances of different sizes during actual grid operation. Among them, the most serious fault is the grid N-2 (two components such as transmission lines and transformers fail simultaneously). In particular, the N-2 fault on the power source side, where power is transmitted through important AC transmission channels, is the most severe fault mode of the system. After this fault occurs, the transfer, impact, and power loss of a large capacity active power flow will have a serious impact on the system. If relevant stability control measures are not taken, the entire power grid will face the serious risk of losing stable operation (power angle instability, voltage instability, AC frequency instability) and system collapse. The direct consequence is a large-scale power outage in the receiving end area.

[0053] To address and prevent this serious fault, the power system is equipped with safety and stability control devices (functions include various safety and stability control systems and corresponding stability strategies). The main stability control strategy is: when a grid N-2 fault occurs, technical measures such as power source disconnection, load disconnection, and adjustment of conventional DC power are typically adopted. When a grid N-2 fault occurs, the degree of disturbance and damage to the system caused by faults in various N-2 components varies, resulting in different levels of disruption. Therefore, the number of power sources to be disconnected will also vary.

[0054] If the amount of generator tripping is small, the impact on the overall active power deficit (corresponding to the AC frequency) is minimal and falls within the allowable safe frequency difference range of the entire network. In this case, the system can be considered to be able to withstand the amount of generator tripping, and the AC stability control system will automatically implement the generator tripping measures. If the amount of generator tripping is large, the impact on the overall active power deficit (corresponding to the AC frequency) is significant, exceeding the allowable safe frequency difference range of the entire network. In this case, the power grid faces the risk of low-frequency operation. To address and avoid the risk of low-frequency operation of the power grid, a dedicated AC / DC coordination control system and related stability control strategies and early warning mechanisms are added to the power system (a safety early warning mechanism for uploading information on the total amount of generator tripping under severe fault conditions of the AC stability control system).

[0055] Specifically, this includes: 1) Start-up valve threshold data uploaded by the AC stability control system for total off-grid data. The value is currently determined by the power dispatching department based on the total installed capacity and start-up method of the power grid in the region. It is dynamically adjusted as the power grid's capacity increases. This value is also a numerical indicator used by the power grid to judge the severity of faults and the risk of low-frequency operation due to active power deficit. 2) After receiving the first total power cut-off from the AC stability control system and initially determining a severe fault, to avoid the risk of low-frequency operation due to a large active power deficit, the AC / DC coordination control system issues one or more control measures and instructions to the conventional DC stability control system to reduce the power output of UHVDC transmission. After the conventional UHVDC transmission power output is reduced, the active power deficit of the entire network decreases, the AC frequency rises back to a safe operating range, and the entire network maintains safe and stable operation.

[0056] Step 3-A: The multi-terminal flexible DC power grid stability control system will integrate information related to the operating conditions of the multi-circuit flexible DC power grid (including the allowable adjustable DC power margin value that can maintain stable grid operation within a certain period of time). Uploaded to the AC / DC co-control system main station;

[0057] Step 3-B: The AC stability control system uploads relevant information under the N-2 severe fault mode of the power grid (including the total amount of power supply that needs to be switched off). (To the AC / DC co-control system main station.)

[0058] Step 4: After receiving the relevant information uploaded by the AC stability control system and the flexible DC stability control system, the AC / DC co-control system simultaneously compares the data with the relevant data in the stability control strategy table pre-stored in the co-control system and the numerical data such as the adjustable DC power margin of the multi-terminal flexible DC system to determine: (Determine the total power supply value) Is it within the adjustable boost DC power safety margin of a converter station on a certain sending end side of a multi-terminal flexible DC system? Within the range).

[0059] Step 5: The AC / DC co-control system adopts a stability control strategy that prioritizes the use of flexible DC systems to improve the overall network stability level: increasing the adjustable DC power of the flexible DC section. Furthermore, the AC stabilization system no longer needs to take stabilization measures such as cutting off the power supply at the sending end. The AC / DC co-control system issues stabilization measures and specific DC power increase commands to the multi-terminal flexible DC system to increase the flexible DC power. .

[0060] Step 6: The AC / DC co-control system adopts a stability control strategy that prioritizes the use of flexible DC systems to improve the overall network stability level.

[0061] Stability control measures to increase DC power in multi-terminal flexible DC systems. ;

[0062] For the need to issue orders to the AC stability control system to cut off part of the power unit capacity Furthermore, this aligns with the preset threshold for power reduction in multi-circuit DC transmission projects set by the power dispatching department. Perform data comparison and judgment: If If established, the AC / DC co-control system will issue a command to the AC stability control system to cut off part of the power supply to the generator unit capacity. .

[0063] Step 7: The AC / DC co-control system adopts a stability control strategy that prioritizes the use of flexible DC systems to improve the overall network stability level: If Established,

[0064] Issue orders and instructions to the AC stability control system to cut off the capacity of some power sources (hydropower units and new energy grid-connected lines) at the sending end of the generating unit for capacity stabilization. ;

[0065] Issue control measures and instructions to the multi-circuit DC stabilization system to reduce the power output of one or more UHVDC lines. .

[0066] Step 8: After receiving the relevant control instructions issued by the AC / DC control center, the AC control system, the multi-terminal flexible DC control system, and the multi-circuit UHVDC control system will implement specific generator switching measures, the multi-terminal flexible DC control system will implement flexible DC power enhancement measures, and the UHVDC control system will implement DC power reduction measures.

[0067] Example 2

[0068] like Figure 2 As shown in Example 1, Example 2 of the present invention proposes a power stabilization system for a wide-area AC / DC hybrid power system based on a power stabilization method for a wide-area AC / DC hybrid power system.

[0069] Specifically, the system includes a multi-source data acquisition subsystem, which is used to acquire real-time operating data of AC grid, UHVDC grid and multi-terminal flexible DC grid in the wide-area AC-DC hybrid power grid through multi-source data acquisition, and construct a real-time power grid operating data matrix;

[0070] The AC stability control subsystem is used to calculate the total number of power generation trips in the AC power grid based on the pre-set stability control strategy and the real-time operation data matrix of the power grid when N-2 or more faults occur in the AC power transmission channel of the power source in the wide-area AC-DC hybrid power system.

[0071] The multi-terminal flexible DC stabilization subsystem is used to calculate the DC adjustable power regulation margin data of the multi-terminal flexible DC grid based on the real-time operation data matrix of the power grid.

[0072] The AC / DC coordinated safety and stability control subsystem is used to make data judgments based on the total power supply tripping data, DC adjustable power adjustment margin data, and UHVDC grid gate threshold data, and transmit stability control execution commands to the AC stability control subsystem, the multi-terminal flexible DC stability control subsystem, and the DC stability control subsystem respectively according to the judgment results.

[0073] The conventional UHVDC stabilization subsystem is used to perform power reduction operations on the UHVDC grid according to the stabilization execution command.

[0074] Specifically, the workflow of this system is as follows:

[0075] First, the multi-source data acquisition subsystem continuously acquires information such as frequency, voltage, active power, reactive power, unit speed and power angle on the AC side. At the same time, it acquires information such as DC power, voltage, port occupancy, and converter valve thermal stability margin on the multi-terminal flexible DC side, as well as power, control mode and pole pair status on the conventional DC side, forming a complete real-time power grid operation data matrix.

[0076] Then, the AC stability control subsystem detects whether N-2 or more serious faults have occurred in the critical transmission channels based on the data matrix and fault criteria, and calculates the total amount of power supply to be cut off at the sending end; at the same time, the multi-terminal flexible DC stability control subsystem calculates the available DC power regulation margin and performs safety boundary verification.

[0077] Next, the AC / DC coordinated safety and stability control subsystem comprehensively judges the AC side power cut-off demand, the multi-terminal flexible DC power adjustment margin, and the conventional UHVDC gate threshold: if the flexible DC adjustment margin is sufficient to cover the power cut-off demand, a flexible DC power increase command is directly issued and the AC side power cut-off is waived; if it can only partially cover the demand, flexible DC power adjustment is used first, and the remaining insufficient part is achieved through the AC side power cut-off; if the power cut-off demand still exceeds the flexible DC adjustment margin and reaches the threshold, a power reduction command is issued to the conventional UHVDC side on the basis of the above.

[0078] Then, each execution subsystem performs specific operations according to the instructions issued by the coordination subsystem: the multi-terminal flexible DC side rapidly increases power, the AC side switches off in batches, the conventional DC side reduces power proportionally, and the execution feedback is transmitted back in real time.

[0079] Finally, the coordination subsystem performs closed-loop correction of frequency deviation and power imbalance based on measurement feedback. After the faulty component is restored, the stability control system withdraws the stability control measures in sequence according to the plan, including the flexible DC return to the set grid operating conditions, the gradual reconnection of the generating units, and the restoration of conventional UHVDC. The system also records the measurement and command logs throughout the process and feeds the data back into the strategy library for post-evaluation and strategy optimization.

[0080] Example 3

[0081] like Figure 4 As shown in the figure, based on Embodiment 1, Embodiment 3 proposes a terminal device for a power stabilization and control method for a wide-area AC / DC hybrid power system. The terminal device 200 includes at least one memory 210, at least one processor 220, and a bus 230 connecting different platform systems.

[0082] The memory 210 may include a readable medium in the form of volatile memory, such as RAM 211 and / or cache memory 212, and may further include ROM 213.

[0083] The memory 210 also stores a computer program, which can be executed by the processor 220. This causes the processor 220 to execute any of the power stabilization methods for wide-area AC / DC hybrid power systems described in the embodiments of this application. The specific implementation and technical effects are consistent with those described in the embodiments of the above methods, and some details will not be repeated here. The memory 210 may also include a program / utility 214 having a set (at least one) of program modules 215. Such program modules include, but are not limited to, an operating system, one or more application programs, other program modules, and program data. Each or some combination of these examples may include an implementation of a network environment.

[0084] Accordingly, processor 220 can execute the aforementioned computer program, as well as executable program / utility 214.

[0085] Bus 230 can represent one or more of several types of bus structures, including a memory bus or memory controller, peripheral bus, graphics acceleration port, processor, or a local bus using any of the various bus structures.

[0086] Terminal device 200 can also communicate with one or more external devices 240, such as keyboards, pointing devices, Bluetooth devices, etc., and with one or more devices capable of interacting with it, and / or with any device that enables it to communicate with one or more other computing devices (e.g., routers, modems, etc.). This communication can be performed via I / O interface 250. Furthermore, terminal device 200 can communicate with one or more networks (e.g., local area networks (LANs), wide area networks (WANs), and / or public networks, such as the Internet) via network adapter 260. Network adapter 260 can communicate with other modules of terminal device 200 via bus 230. It should be understood that, although not shown in the figures, other hardware and / or software modules can be used in conjunction with terminal device 200, including but not limited to: microcode, device drivers, redundant processors, external disk drive arrays, RAID systems, tape drives, and data backup storage platforms.

[0087] Example 4

[0088] like Figure 5 As shown, based on Embodiment 1, this embodiment proposes a computer-readable storage medium for a power stabilization and control method for a wide-area AC / DC hybrid power system. The computer-readable storage medium stores instructions that, when executed by a processor, implement any of the aforementioned power stabilization and control methods for a wide-area AC / DC hybrid power system. Its specific implementation method is consistent with the implementation methods and achieved technical effects described in the embodiments of the above methods, and some details will not be repeated.

[0089] Figure 5 The illustration shows a program product 300 for implementing the above-described method, which may employ a portable compact disc read-only memory (CD-ROM) and include program code, and may run on a terminal device, such as a personal computer. However, the program product 300 of the present invention is not limited thereto. In this embodiment, the readable storage medium may be any tangible medium containing or storing a program that may be used by or in conjunction with an instruction execution system, apparatus, or device. The program product 300 may employ any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: an electrical connection having one or more wires, a portable disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disc read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof.

[0090] Computer-readable storage media may include data signals propagated in baseband or as part of a carrier wave, carrying readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A readable storage medium may also be any readable medium other than a readable storage medium, capable of sending, propagating, or transmitting a program for use by or in conjunction with an instruction execution system, apparatus, or device. The program code contained on the readable storage medium may be transmitted using any suitable medium, including but not limited to wireless, wired, optical fiber, RF, etc., or any suitable combination thereof. Program code for performing operations of the present invention may be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java, C++, etc., and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on a user computing device, partially on a user device, as a standalone software package, partially on a user computing device and partially on a remote computing device, or entirely on a remote computing device or server. In cases involving remote computing devices, the remote computing devices can be connected to user computing devices via any type of network, including local area networks (LANs) or wide area networks (WANs), or they can be connected to external computing devices (e.g., via the Internet using an Internet service provider).

[0091] This invention is described from the perspectives of its intended use, effectiveness, progress, and novelty. Its practical and progressive features meet the functional enhancement and use requirements emphasized by the Patent Law. The above description and drawings are merely preferred embodiments of this application and are not intended to limit this application. Therefore, all structures, devices, features, etc., that are similar to or identical to those of this application, i.e., all equivalent substitutions or modifications made in accordance with the scope of this patent application, shall fall within the scope of protection of this patent application.

[0092] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A power stabilization and control method for a wide-area AC / DC hybrid power system, characterized in that, Includes the following steps: S1. By acquiring multi-source data, obtain real-time operation data of AC power grid, conventional UHVDC power grid and multi-terminal flexible DC power grid within the wide-area AC / DC hybrid power system, and construct a real-time power grid operation data matrix; S2. Calculate the DC adjustable power regulation margin data of the multi-terminal flexible DC grid based on the real-time operation data matrix of the power grid. ; S3. When an N-2 or higher fault occurs in the AC transmission channel of a power source in a wide-area AC / DC hybrid power system, the total number of power source trips in the AC power grid is calculated based on the pre-set AC grid stability control strategy and the real-time grid operation data matrix. Data on the total number of power supply trips. With preset start-up threshold data for wide-area AC / DC hybrid power systems Perform data size judgment: when Data less than the gate valve threshold Then, based on the total number of power supply trips... Disconnect the power supply from the AC mains; otherwise, proceed to step S4. S4. Data on the adjustment margin of multi-terminal flexible DC adjustable power Total power supply switching data Perform data size determination: When the margin data Greater than the total number of power supply trips At the same time, based on the pre-set stability control strategy, the adjustable DC power value of the multi-terminal flexible DC grid is increased. ; When the margin data Less than or equal to the total number of power supply trips At the same time, based on the pre-set stability control strategy, the adjustable DC power value of the multi-terminal flexible DC grid is increased. And based on the improved multi-terminal flexible DC adjustable power value The total number of second power source trips in the AC power grid was calculated. ; S5. Total data on the second power supply tripping. Valve threshold data Perform data size determination: When the total number of second power supply switches is data Data less than the gate valve threshold Then, based on the total number of power supply trips... Disconnect the power source from the AC power grid; When the second power supply is switched off in total Data greater than or equal to the valve threshold data Then, based on the total number of power supply trips... Disconnect power sources from the AC power grid and reduce the DC power output of the conventional UHVDC power grid. .

2. The power stabilization and control method for a wide-area AC / DC hybrid power system according to claim 1, characterized in that, The real-time operation data of the power grid includes generator power angle data, AC power grid voltage data, AC power grid power data, AC power grid frequency data, DC power data and DC voltage data of conventional UHVDC power grids and multi-terminal flexible DC power grids.

3. The power stabilization and control method for a wide-area AC / DC hybrid power system according to claim 1, characterized in that, The stability control strategy includes disconnecting hydropower units on the power supply side of the sending end, disconnecting new energy grid-connected lines on the power supply side of the sending end, and modulating multi-terminal flexible DC power and modulating multi-circuit ultra-high voltage DC power.

4. A power stabilization and control method for a wide-area AC / DC hybrid power system according to claim 1, characterized in that, In step S2, based on the real-time operating data of the converter stations at the sending and receiving ends of the multi-terminal flexible DC grid and the DC grid, it is calculated whether there is DC adjustable power margin data that meets the safety requirements of flexible DC grid during the current time period. .

5. A power stabilization and control method for a wide-area AC / DC hybrid power system according to claim 1, characterized in that, In step S3, when a severe fault N-2 occurs in the AC grid of the wide-area AC / DC hybrid power system, the power generation units in the AC grid are disconnected according to the preset stability control strategy, and the total number of disconnected power generation units is determined. Valve threshold data Is the data size relationship... If so, proceed to step S4.

6. A power stabilization and control method for a wide-area AC / DC hybrid power system according to claim 1, characterized in that, In step S4, when an N-2 severe fault occurs in the AC grid of a wide-area AC / DC hybrid power system, the adjustable DC power value of the multi-terminal flexible DC grid is preferentially increased. The stability control strategy, and based on the improved multi-terminal flexible DC adjustable power value The total number of second power source trips in the AC power grid was calculated. .

7. A power stabilization and control system for a wide-area AC / DC hybrid power system, the system being implemented based on a power stabilization and control method for a wide-area AC / DC hybrid power system as described in any one of claims 1-6, characterized in that, include: The multi-source data acquisition subsystem is used to acquire real-time operating data of AC power grid, conventional DC power grid and multi-terminal flexible DC power grid in a wide-area AC / DC hybrid power system through multi-source data acquisition, and to construct a real-time power grid operating data matrix. The AC stability control subsystem is used to calculate the total number of AC power generation trips based on the pre-set stability control strategy and the real-time operation data matrix of the power grid when N-2 or more faults occur in the AC power transmission channel of the wide-area AC-DC hybrid power system. The multi-terminal flexible DC stabilization subsystem is used to calculate the DC adjustable power regulation margin data of the multi-terminal flexible DC grid based on the real-time operation data matrix of the power grid. The AC / DC coordinated safety and stability control subsystem is used to make data judgments based on the total power supply tripping data, DC adjustable power adjustment margin data, and gate threshold data for the start-up of conventional UHVDC grids, and transmit stability control execution commands to the AC stability control subsystem, the multi-terminal flexible DC stability control subsystem, and the conventional UHVDC stability control subsystem respectively according to the judgment results. The conventional UHVDC stabilization subsystem is used to perform power reduction operations on the UHVDC grid according to the stabilization execution command.

Images