Digital twin operation and maintenance platform in power system

Abstract

The invention discloses a digital twinborn operation and maintenance platform in an electric power system, and relates to the technical field of digital twinborn, and the platform comprises a collection module which collects the real-time operation data of a power grid, inputs the real-time operation data of the power grid into a digital twinborn body of the power grid for simulation calculation, and outputs a real-time simulation working condition of the power grid; the analysis module is used for performing relay protection constant value checking and oscillation stability analysis on protection parameters and generator set control parameters in the digital twin of the power grid by utilizing the real-time power grid simulation working condition, and generating a checking result and an oscillation analysis report; the execution module is used for executing collaborative optimization simulation in the digital twin of the power grid based on the check result and the oscillation analysis report to generate a coordination strategy; and the feedback module issues the coordination strategy to relay protection equipment and a new energy power station controller. According to the method, the wide-area measurement data are input into the digital twin of the power grid for simulation calculation, so that accurate mapping of the physical power grid state is realized.

Description

Technical Field

[0001] This invention relates to the field of digital twin technology, and in particular to a digital twin operation and maintenance platform for power systems. Background Technology

[0002] With the transformation of the energy structure and the continuous expansion of the power grid, the complexity of power system operation has increased significantly, placing higher demands on operation and maintenance technologies. The high penetration rate of new energy sources has altered the dynamic characteristics of the traditional power grid, increasing the uncertainty of system operation. The safe and stable operation of the power grid urgently requires more precise state perception and decision support mechanisms. Digital twin technology, as a bridge between the physical world and the information space, provides a new dimension of cognition and control for the power system. By constructing a virtual mapping of the power grid and combining it with real-time operational data, it enables accurate description, advanced prediction, and optimized control of the physical power grid. The construction of digital twins for the power system has become a key link in the development of smart grids. Its core value lies in achieving deep integration of physical and information systems, supporting comprehensive perception, accurate assessment, and collaborative optimization of the power grid's operating status, and providing technical guarantees for the safe and economical operation of the power system.

[0003] Current power system simulation and analysis technologies have limitations in dynamic collaborative parameter optimization. Relay protection setting verification and generator set oscillation stability analysis are often conducted independently, lacking a unified optimization framework and making it difficult to adapt to real-time changes in grid operating conditions. Insufficient data interoperability between different functional modules results in a lack of a global perspective in adjusting protection and control system parameters. Especially with the increasing proportion of renewable energy sources, this separate analysis model struggles to cope with rapid changes in system dynamic characteristics. Existing technologies suffer from insufficient real-time performance and a lack of global perspective in parameter collaborative optimization, typically employing a combination of phased manual intervention and periodic offline verification to compensate, which is insufficient to meet the urgent needs of modern power grids for real-time collaborative control. Summary of the Invention

[0004] In view of the aforementioned existing problems, the present invention is proposed.

[0005] Therefore, this invention provides a digital twin operation and maintenance platform for power systems to solve the problem of failing to meet the urgent need for real-time collaborative control in modern power grids.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: In a first aspect, the present invention provides a digital twin operation and maintenance platform for a power system, comprising, The data acquisition module collects real-time power grid operation data, inputs the real-time power grid operation data into the power grid digital twin for simulation calculation, and outputs real-time power grid simulation operating conditions. The analysis module uses real-time power grid simulation conditions to perform relay protection setting verification and oscillation stability analysis on the protection parameters and generator control parameters in the power grid digital twin, generating verification results and oscillation analysis reports; The execution module, based on the verification results and oscillation analysis report, performs collaborative optimization simulation in the power grid digital twin to generate coordination strategies; The feedback module distributes the coordination strategy to the relay protection equipment and the new energy power station controller, and verifies the execution effect of the coordination strategy based on the feedback data of the wide-area measurement array.

[0007] As a preferred embodiment of the digital twin operation and maintenance platform in the power system described in this invention, the output of real-time power grid simulation conditions is specifically as follows: The real-time operation data of the power grid is transmitted to the data processing center. The data processing center performs topology verification and bad data identification on the real-time operation data of the power grid based on the power grid component parameter library, and generates a computable dataset of the power grid. The computable dataset of the power grid is input into the digital twin of the power grid. Based on the physical laws of the power network, the digital twin of the power grid performs network topology construction and electrical state analysis on the computable dataset of the power grid and outputs a set of electrical state variables. The set of electrical state variables is mapped to the nodes and branch parameters of the pre-constructed grid model of the power grid digital twin to form a real-time power grid simulation condition.

[0008] As a preferred embodiment of the digital twin operation and maintenance platform in the power system described in this invention, the generation of verification results and oscillation analysis reports is specifically as follows: Analyze the power grid topology and current operating mode in real-time power grid simulation conditions; Based on the power grid topology, the protection range to be checked is determined and a check instruction is generated; based on the current operating mode, the generator sets to be scanned are determined and an oscillation scan instruction is generated. According to the verification command, short-circuit current analysis and upper and lower limit comparison of the protection parameters of the power grid digital twin are performed. At the same time, according to the oscillation scan command, oscillation mode identification and damping characteristic evaluation are performed on the generator control parameters in the power grid digital twin. The results of short-circuit current analysis and the conclusions of setting value comparison are summarized to form the setting value verification conclusion. The results of oscillation mode identification and the conclusions of damping characteristic evaluation are integrated to form the stability evaluation conclusion. The setpoint verification conclusions and stability assessment conclusions are compiled into a structured document, and the verification results and oscillation analysis report are output.

[0009] As a preferred embodiment of the digital twin operation and maintenance platform in the power system described in this invention, the step of determining the protection range to be verified and generating verification instructions involves identifying a set of protection devices that are electrically adjacent and have protection coordination relationships based on the power grid topology connection relationship, defining the protection device set as the protection range to be verified, and generating setting verification instructions for all protection devices within the protection range.

[0010] As a preferred embodiment of the digital twin operation and maintenance platform in the power system described in this invention, the step of determining the generator set to be scanned and generating an oscillation scan command is based on the generator output distribution and power flow of the grid interconnection line under the current operating mode, identifying the dominant oscillation mode with a participation factor greater than a preset factor threshold, locating the generator set dynamically coupled with the dominant oscillation mode, defining the generator set as the generator set to be scanned, and generating an oscillation scan command for the generator set to be scanned.

[0011] As a preferred embodiment of the digital twin operation and maintenance platform in the power system described in this invention, the participation factor is a modal analysis parameter that quantifies the degree of participation of the generator set in the dynamic response of the power oscillation mode.

[0012] As a preferred embodiment of the digital twin operation and maintenance platform in the power system described in this invention, the generation and coordination strategy is specifically as follows: Extract protection setting adjustment items from the verification results, and extract oscillation suppression parameter optimization items from the oscillation analysis report; Based on the protection setting adjustment term and the oscillation suppression parameter optimization term, a combined strategy space is constructed in the power grid digital twin. The combined strategy space is then verified by transient stability simulation in conjunction with real-time power grid simulation conditions, and a strategy simulation set is generated. Based on the strategy simulation set, evaluate the protection action and damping level of each strategy in the combined strategy space, screen out strategies whose protection action and damping level both meet the feasible threshold, and combine them to generate a feasible strategy set. Select the strategy with the smallest adjustment range of the setpoint and the smallest adjustment range of the oscillation suppression parameter from the set of feasible strategies, and with the best suppression effect, as the coordination strategy.

[0013] As a preferred embodiment of the digital twin operation and maintenance platform in the power system described in this invention, the generation strategy simulation set is specifically as follows: In the digital twin of the power grid, the protection setting adjustment item and the oscillation suppression parameter optimization item are combined to generate a combined strategy space; Set the real-time power grid simulation conditions as the initial simulation state for each strategy in the combined strategy space; In the digital twin of the power grid, transient stability simulation is performed on each strategy in the combined strategy space in sequence to simulate the dynamic response of the digital twin power grid under preset disturbances and record the dynamic response data corresponding to each strategy. All dynamic response data are aggregated to generate a strategy simulation set.

[0014] As a preferred embodiment of the digital twin operation and maintenance platform in the power system described in this invention, the feedback data verification of the coordination strategy based on the wide-area measurement array is specifically as follows: Analysis of the protection setpoint adjustment scheme and oscillation suppression parameter setting scheme in the coordination strategy; Convert the protection setting adjustment scheme into a protection setting command, and convert the oscillation suppression parameter setting scheme into a control command; The protection setting command is sent to the target relay protection equipment, the control command is sent to the target new energy power station controller, and the command execution confirmation signal is received. Based on the command execution confirmation signal, the actual operation data of the power grid is collected through a wide-area measurement array to monitor the relay protection action and the power grid oscillation mode; The relay protection actions are compared with the expected protection objectives of the coordination strategy, and the grid oscillation modes are compared with the expected damping improvement objectives of the coordination strategy. Protection verification conclusions and damping improvement verification conclusions are generated respectively to complete the evaluation of the effectiveness of the coordination strategy.

[0015] As a preferred embodiment of the digital twin operation and maintenance platform in the power system described in this invention, the instruction execution confirmation signal is a signal returned by the target relay protection device and the target new energy power station controller.

[0016] The beneficial effects of this invention are as follows: By inputting wide-area measurement data into a digital twin of the power grid for simulation calculations, a precise mapping of the physical power grid state is achieved. The digital twin performs topology verification and bad data identification on the original data, constructs topology relationships based on the physical laws of power networks, and analyzes the electrical state to form real-time simulation conditions. Precise real-time simulation allows relay protection setting verification and oscillation stability analysis to be performed in advance in the virtual environment, predicting and optimizing protection parameters and generator control parameters. The real-time simulation technology of the power grid digital twin avoids the lag of traditional operation and maintenance relying on offline analysis, significantly improving the safe and stable operation capability of the power grid, reducing fault risks, and providing reliable technical support for intelligent management of the power system. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of a digital twin operation and maintenance platform in a power system. Figure 2 A flowchart generated for the verification results and oscillation analysis report; Figure 3 A flowchart generated for the coordination strategy; Figure 4 A flowchart for verifying the effectiveness of the coordination strategy. Detailed Implementation

[0019] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0020] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0021] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0022] Reference Figures 1-4 As one embodiment of the present invention, this embodiment provides a digital twin operation and maintenance platform for a power system, comprising the following steps: The data acquisition module collects real-time power grid operation data, inputs the real-time power grid operation data into the power grid digital twin for simulation calculation, and outputs real-time power grid simulation operating conditions.

[0023] Voltage phasor measurement data, circuit breaker status signals, and generator active and reactive power output data of the bus nodes in the power grid are collected by a wide-area measurement array to form real-time power grid operation data.

[0024] The real-time operation data of the power grid is transmitted to the data processing center. The data processing center performs topology verification and bad data identification on the real-time operation data of the power grid based on the power grid component parameter library, and generates a computable dataset of the power grid.

[0025] Specifically, after the real-time operation data of the power grid is transmitted to the data processing center, the data processing center extracts the circuit breaker status signal from the real-time operation data of the power grid and compares it one by one with the connection relationship in the power grid component parameter library to verify the integrity of the power grid topology connection relationship and mark the mismatch position as the topology verification anomaly.

[0026] Simultaneously, voltage phasor measurement data, generator active power output data, and generator reactive power output data are extracted and compared point-by-point with the historical ranges of voltage phasor measurement data (determined based on equipment rated parameters and long-term operation monitoring data, e.g., 0.9-1.1 pu), generator active power output data (determined based on generator rated capacity and dispatch operation history, e.g., 210MW-660MW), and generator reactive power output data (determined based on generator PQ operating capacity curve, power factor limitations, and grid voltage regulation requirements, e.g., -150Mvar to +300Mvar) in the power grid component parameter library. This is to identify data that exceeds the range (e.g., voltage phasor 0.9-1.1 pu, active power output 210MW-660MW, reactive power output -150Mvar to +300Mvar) as bad data and record the specific values ​​and source nodes.

[0027] Remove all marked topology verification anomalies and bad data, and retain the remaining voltage phasor measurement data, circuit breaker status signals, generator active power output data, and generator reactive power output data to form a computable dataset for the power grid.

[0028] Among them, the power grid component parameter library is an existing database used to store information such as power grid equipment specifications, connection relationships, historical range of voltage phasor measurement data, historical range of generator active power output data, and historical range of generator reactive power output data, and supports topology verification and bad data identification of real-time power grid operation data.

[0029] The computable dataset of the power grid is input into the digital twin of the power grid. Based on the physical laws of the power network, the digital twin of the power grid performs network topology construction and electrical state analysis on the computable dataset of the power grid and outputs a set of electrical state variables. Specifically, the digital twin of the power grid extracts the opening and closing position information from the circuit breaker status signals in the computable dataset of the power grid and matches them one by one with the connection relationships in the power grid component parameter library to confirm the matched circuit breaker path as a valid branch, thereby constructing the network topology relationship (including valid branch connections and isolation paths between bus nodes).

[0030] Simultaneously, the injected power and measured phasor values ​​of the nodes are extracted from the voltage phasor measurement data, generator active power output data, and generator reactive power output data in the computable dataset of the power grid. State balance adjustment is then performed according to the physical laws of the power network (i.e., the node voltage is iteratively solved using the weighted least squares method to minimize the sum of squared weighted residuals between the calculated and measured values, while satisfying the constraints of Kirchhoff's current and voltage laws) to confirm the voltage amplitude, voltage phase angle, branch power flow direction, and branch power flow amplitude of each bus node, thereby analyzing the electrical state (including the set of voltage amplitudes, voltage phase angles, branch power flow directions, and branch power flow amplitudes of all bus nodes).

[0031] The voltage amplitude set, voltage phase angle set, branch power flow direction set, and branch power flow amplitude set are integrated into an electrical state variable set and the electrical state variable set is output.

[0032] The least squares method is a well-known mathematical method proposed by Gauss and belongs to the public domain. The physical laws of power networks mainly refer to Ohm's law, Kirchhoff's voltage law, and Kirchhoff's current law, which respectively describe the relationship between current and voltage in a conductor, the sum of voltage drops in a closed loop being zero, and the sum of inflow currents at nodes being equal to the sum of outflow currents. They are used to describe the balance and flow relationship of current, voltage, and impedance in power systems.

[0033] The electrical state variable set is mapped to the pre-built grid model nodes and branch parameters of the power grid digital twin, forming a real-time power grid simulation condition that is consistent with the current operating state of the physical power grid.

[0034] Specifically, this involves extracting all bus node identifiers and valid branch identifiers from the predefined power grid topology (based on the power grid physical connection structure and historical construction archives) from the power grid digital twin, and extracting the voltage amplitude set, voltage phase angle set, branch power flow direction set, and branch power flow amplitude set from the electrical state variable set.

[0035] The voltage amplitude set and voltage phase angle set are matched one by one with all bus node identifiers to confirm the voltage amplitude value and voltage phase angle value corresponding to each bus node identifier, thereby mapping the voltage amplitude value and voltage phase angle value to the corresponding bus node identifier.

[0036] Simultaneously, the set of branch current direction and the set of branch current amplitude are matched one by one with the valid branch identifiers to confirm the current direction value and current amplitude value corresponding to each valid branch identifier, thereby mapping the current direction value and current amplitude value to the corresponding valid branch identifier.

[0037] The voltage amplitude and voltage phase angle values ​​on all bus node identifiers and the power flow direction and power flow amplitude values ​​on effective branch identifiers are integrated into a real-time power grid simulation condition to ensure that the real-time power grid simulation condition is consistent with the current operating state of the physical power grid. This includes the voltage amplitude distribution, voltage phase angle distribution, power flow direction distribution, and power flow amplitude distribution of all bus nodes and branches.

[0038] The analysis module uses real-time power grid simulation conditions to perform relay protection setting verification and oscillation stability analysis on the protection parameters and generator control parameters in the power grid digital twin, generating verification results and oscillation analysis reports.

[0039] This paper analyzes the power grid topology and current operating mode in a real-time power grid simulation. Based on the power grid topology, it determines the protection range to be checked and generates a check command; based on the current operating mode, it determines the generator units to be scanned and generates an oscillation scan command.

[0040] Specifically, this involves identifying a set of protection devices that are electrically adjacent and have protection coordination relationships based on the power grid topology connection relationship (that is, representing the power grid topology connection relationship as a directed graph, where bus nodes are nodes and effective branches are edges).

[0041] The graph traversal algorithm (such as breadth-first search) expands the search from the starting node of each protection device to adjacent protection devices whose electrical distance does not exceed a preset number of trips (set based on power system protection principles and fault current attenuation characteristics to ensure coverage of the main and backup coordination area of ​​adjacent protection devices, such as 2-3 trips). The main and backup coordination relationship is confirmed by cross-comparison (i.e. by comparing the operating parameters, protection type and setting limits of each protection device to confirm whether an effective main and backup coordination relationship is formed between each protection device to ensure that only the protection device closest to the fault point operates when a fault occurs, avoiding cascading trips). The protection configuration table of the protection device set is used to confirm the main and backup coordination relationship, thereby identifying the protection device set that is electrically close and has a protection coordination relationship.

[0042] Define the set of protection devices as the protection range to be verified, and generate setting verification instructions for all protection devices within the protection range.

[0043] Based on the generator output distribution and grid interconnection power flow under the current operating mode, the dominant oscillation mode with a participation factor greater than a preset factor threshold is identified, and the generator set dynamically coupled with the dominant oscillation mode is located.

[0044] Define the generator set as the generator set to be scanned, and generate an oscillation scan command for the generator set to be scanned.

[0045] The preset factor threshold is set based on the offline modal baseline and historical oscillation events. For example, the typical value range is 0.05 to 0.1. The advantage of a value of 0.05 to 0.1 is that it effectively filters noise to focus on the participation of the dominant generator set and avoids overscanning irrelevant equipment. A higher value (such as 0.2) may ignore secondary but potentially risky coupled generator sets, resulting in an incomplete stability assessment. A lower value (such as 0.01) will include too many low-contribution generator sets, increasing the computational burden and false positives. The participation factor is a modal analysis parameter that quantifies the degree of participation of generator sets in the dynamic response of power oscillation modes.

[0046] The expression for the participation factor is: ; In the formula, For the first The participation factor of a state variable (such as generator rotor angle or speed) in a fixed mode. The left eigenvector (fixed mode) is the first... Each element reflects the modal observation sensitivity (the influence of the state on the modal output). The right eigenvector (fixed mode) is the first... Each element reflects modal control sensitivity (the influence of input on the state). It serves as an index for state variables, used to identify the position of a specific generator or device's dynamic state variable within a mode.

[0047] According to the verification command, short-circuit current analysis and upper / lower limit comparison of the protection parameters of the power grid digital twin are performed. Simultaneously, according to the oscillation scan command, oscillation mode identification and damping characteristic evaluation are performed on the generator control parameters in the power grid digital twin; specifically as follows: The power grid digital twin extracts the fault locations and upper and lower limits of the set values ​​of all protection devices within the protection range from the verification instructions, and is based on the voltage amplitude distribution, voltage phase angle distribution, branch power flow direction distribution, power flow amplitude distribution, and network topology relationship in the real-time power grid simulation conditions.

[0048] For each protection device fault location, a short-circuit fault simulation is performed (i.e., by setting a fault point at the corresponding location of the protection device, applying short-circuit boundary conditions, and tracing the actual flow path of current in the power grid topology), confirming the current path flow from the generator active power output data and generator reactive power output data in the short-circuit fault simulation, thereby extracting the short-circuit current value corresponding to each protection device location.

[0049] After the short-circuit current analysis is completed, the power grid digital twin continues to compare the extracted short-circuit current value with the upper and lower limits of the protection parameters one by one to confirm whether the short-circuit current value falls within the normal range of the upper and lower limits of the settings. This marks the short-circuit current value of each protection device as conforming or not conforming to the status, forming a conclusion on the comparison between the short-circuit current analysis result and the upper and lower limits of the settings.

[0050] The upper and lower limits of relay protection settings are based on the rated parameters and safety margins of the power grid equipment. For example, the lower limit of overcurrent protection is 1.05 to 1.2 times the rated current, and the upper limit is 0.6 to 0.8 times the maximum short-circuit current, in order to balance sensitivity and selectivity.

[0051] The digital twin of the power grid extracts the identifier of the generator set to be scanned and the damping parameters in the generator set control parameters from the oscillation scan command, and then uses the voltage amplitude distribution, voltage phase angle distribution, branch power flow direction distribution and power flow amplitude distribution, as well as network topology, in the real-time power grid simulation.

[0052] Small disturbance simulation is performed on the identified generator sets to be scanned (i.e., by applying small disturbances to the active or reactive power output of the generator sets to be scanned, the dynamic response trajectory of the power grid is monitored), and the dynamic response path of the generator active power output data and generator reactive power output data source in the small disturbance simulation is confirmed, thereby extracting the oscillation response value corresponding to each generator set to be scanned.

[0053] After the oscillation pattern identification is completed, the power grid digital twin continues to compare the extracted oscillation response value with the damping parameter in the generator control parameters one by one to confirm whether the oscillation response value matches the stable range of the damping parameter (based on the power dynamic stability setting, such as a damping ratio greater than 5% to 10% to ensure that the oscillation response decays rapidly rather than continuously amplifies). This marks the stable or unstable state of the oscillation response value of each generator to be scanned, forming the oscillation pattern identification result and the damping characteristic evaluation conclusion.

[0054] The results of short-circuit current analysis are summarized and compared with the setpoint to form a setpoint verification conclusion. The results of oscillation mode identification and damping characteristic evaluation are integrated to form a stability evaluation conclusion.

[0055] The setpoint verification conclusions and stability assessment conclusions are compiled into a structured document, and the verification results and oscillation analysis report are output.

[0056] The execution module performs collaborative optimization simulation in the power grid digital twin based on the verification results and oscillation analysis report, and generates coordination strategies.

[0057] Extract protection setting adjustment items from the verification results, and extract oscillation suppression parameter optimization items from the oscillation analysis report.

[0058] Based on the protection setting adjustment term and the oscillation suppression parameter optimization term, a combined strategy space is constructed in the power grid digital twin. The combined strategy space is then verified through transient stability simulation using real-time power grid simulation conditions, generating a strategy simulation set. The details are as follows: In the digital twin of the power grid, the protection setting adjustment term and the oscillation suppression parameter optimization term are combined to generate a combined strategy space.

[0059] Set the real-time power grid simulation conditions as the initial simulation state for each strategy in the combined strategy space.

[0060] In the digital twin of the power grid, transient stability simulation is performed sequentially for each strategy in the combined strategy space to simulate the dynamic response of the digital twin power grid under preset disturbances (based on typical fault characteristics and historical operation records of the power grid), and the dynamic response data corresponding to each strategy is recorded. Specifically, by applying preset disturbances to the digital twin power grid (such as setting a three-phase short-circuit fault at the protection verification point to check the performance of the protection setting adjustment item and the oscillation suppression parameter optimization item, and recording the generator rotor angle change trajectory and speed deviation trajectory), the rotor angle change path data and speed deviation path data corresponding to each strategy are extracted, and all rotor angle change path data and speed deviation path data are integrated into dynamic response data and recorded as dynamic response data corresponding to each strategy.

[0061] All dynamic response data are aggregated to generate a strategy simulation set.

[0062] Based on the strategy simulation set, evaluate the protection action and damping level of each strategy in the combined strategy space (i.e., verify whether the protection function action time and location after strategy execution meet the fault isolation requirements: when a fault occurs, the protection function must accurately disconnect the faulty part within the specified time limit, while ensuring that the non-faulty area continues to be powered normally; the fault isolation time limit is determined according to the voltage level, for example, 20-30 milliseconds for 220kV lines, 100-200 milliseconds for 10kV lines, and 20-40 milliseconds for bus protection).

[0063] Strategies that satisfy both the protection action and the damping level are selected (i.e., protection action test and damping level test are performed on each strategy in the combined strategy space, and when both test results reach the feasible threshold, the strategy that passes the double test is retained), and combined to generate a set of feasible strategies.

[0064] The feasible threshold is set based on IEEE power stability and historical event experience. For example, the typical range is a damping ratio of 5%-10%. The advantage is that it balances the response decay rate and computational efficiency to ensure grid stability. Taking a higher value (such as 15%) may screen out too few strategies, resulting in conservative optimization. Taking a lower value (such as 3%) may easily include unstable strategies, increasing the risk of instability.

[0065] The expression for the damping level is: ; In the formula, The damping ratio (dimensionless, typically >5% indicates stability). This represents the decay rate, used to quantify the decay rate of the oscillation mode (a negative value indicates stable decay). The oscillation frequency is used to quantify the frequency of the oscillation mode (which determines the oscillation period).

[0066] Select the strategy with the smallest adjustment range of the setpoint and the smallest adjustment range of the oscillation suppression parameter from the set of feasible strategies, and with the best suppression effect, as the coordination strategy.

[0067] Specifically, the power grid digital twin sequentially extracts the setpoint adjustment range, oscillation suppression parameter adjustment range, and suppression effect of each strategy from the set of feasible strategies. It then compares the setpoint adjustment range of each strategy with the setpoint adjustment range of all remaining strategies in the set of feasible strategies to confirm whether it is the smallest setpoint adjustment range among all remaining strategies.

[0068] At the same time, the adjustment range of the oscillation suppression parameter of each strategy is compared with the adjustment range of the oscillation suppression parameter of all remaining strategies in the feasible strategy set to confirm whether it is the smallest adjustment range of the oscillation suppression parameter of all remaining strategies.

[0069] The suppression effect of each strategy is compared one by one with the suppression effects of all remaining strategies in the feasible strategy set to confirm whether it is the best suppression effect among all remaining strategies. Thus, the strategy with the smallest set value adjustment amplitude, the smallest oscillation suppression parameter adjustment amplitude, and the best suppression effect is marked as the coordination strategy.

[0070] The feedback module distributes the coordination strategy to the relay protection equipment and the new energy power station controller, and verifies the execution effect of the coordination strategy based on the feedback data of the wide-area measurement array.

[0071] This paper analyzes the protection setpoint adjustment scheme and oscillation suppression parameter setting scheme in the coordination strategy.

[0072] The protection setting adjustment scheme is converted into protection setting instructions, and the oscillation suppression parameter setting scheme is converted into control instructions. Specifically, the power grid digital twin extracts specific setting values ​​from the protection setting adjustment scheme and encapsulates them into protection setting instructions in a standard protocol format, while simultaneously extracting specific parameter values ​​from the oscillation suppression parameter setting scheme and encapsulating them into control instructions in a standard protocol format.

[0073] The protection setting command is sent to the target relay protection device, the control command is sent to the target new energy power station controller, and the command execution confirmation signal is received; the command execution confirmation signal is a signal returned by the target relay protection device and the target new energy power station controller.

[0074] Based on the command execution confirmation signal, the actual operation data of the power grid is collected through a wide-area measurement array, and the relay protection action and power grid oscillation mode are monitored.

[0075] The relay protection actions are compared with the expected protection objectives of the coordination strategy, and the grid oscillation modes are compared with the expected damping improvement objectives of the coordination strategy. Protection verification conclusions and damping improvement verification conclusions are generated respectively to complete the evaluation of the effectiveness of the coordination strategy.

[0076] Specifically, the data processing center extracts relay protection actions from actual power grid operation data, including action time and location. It then compares these relay protection actions with the expected protection targets of the coordination strategy (set based on power grid safety and historical fault cases, the expected action of relay protection equipment to disconnect the faulty branch and isolate the affected area within a preset time (e.g., 0.1-0.5 seconds) when a fault occurs). This confirms whether the relay protection action time matches the expected protection target time (e.g., action completed within 0.1-0.5 seconds after the fault occurs) and whether the relay protection action location matches the expected protection target location (e.g., in the case of a short-circuit fault in a distribution line, the expected protection target location is to disconnect the circuit breaker of the faulty line to isolate the affected area and prevent the fault from spreading). Based on this, the center marks the relay protection action as either compliant or non-compliant, forming a protection verification conclusion.

[0077] After the matching and comparison are completed, the data processing center continues to extract the grid oscillation mode from the actual operation data of the grid, including the oscillation frequency and oscillation amplitude. The grid oscillation mode is then matched and compared with the expected damping improvement target of the coordination strategy one by one to confirm whether the grid oscillation frequency matches the expected damping improvement target frequency and whether the grid oscillation amplitude matches the expected damping improvement target amplitude. This marks the grid oscillation mode as improved or unimproved, forming a damping improvement verification conclusion.

[0078] After all matching and comparison are completed, the data processing center will integrate the protection verification conclusions and the damping improvement verification conclusions into a coordinated strategy implementation effect evaluation.

[0079] In summary, this invention achieves a precise mapping of the physical power grid state by inputting wide-area measurement data into a digital twin of the power grid for simulation calculations. The digital twin performs topology verification and bad data identification on the original data, constructs topology relationships based on the physical laws of power networks, and analyzes the electrical state to form a real-time simulation operating condition. This accurate real-time simulation allows relay protection setting verification and oscillation stability analysis to be performed in advance in the virtual environment, predicting and optimizing protection parameters and generator control parameters. The real-time simulation technology of the power grid digital twin avoids the lag of traditional operation and maintenance relying on offline analysis, significantly improving the safe and stable operation capability of the power grid, reducing fault risks, and providing reliable technical support for intelligent management of the power system.

[0080] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A digital twin operation and maintenance platform for a power system, characterized in that: include, The data acquisition module collects real-time power grid operation data, inputs the real-time power grid operation data into the power grid digital twin for simulation calculation, and outputs real-time power grid simulation operating conditions. The analysis module uses real-time power grid simulation conditions to perform relay protection setting verification and oscillation stability analysis on the protection parameters and generator control parameters in the power grid digital twin, generating verification results and oscillation analysis reports; The execution module, based on the verification results and oscillation analysis report, performs collaborative optimization simulation in the power grid digital twin to generate coordination strategies; The feedback module distributes the coordination strategy to the relay protection equipment and the new energy power station controller, and verifies the execution effect of the coordination strategy based on the feedback data of the wide-area measurement array.

2. The digital twin operation and maintenance platform in the power system according to claim 1, characterized in that: The output of the real-time power grid simulation conditions is as follows. The real-time operation data of the power grid is transmitted to the data processing center. The data processing center performs topology verification and bad data identification on the real-time operation data of the power grid based on the power grid component parameter library, and generates a computable dataset of the power grid. The computable dataset of the power grid is input into the digital twin of the power grid. Based on the physical laws of the power network, the digital twin of the power grid performs network topology construction and electrical state analysis on the computable dataset of the power grid and outputs a set of electrical state variables. The set of electrical state variables is mapped to the nodes and branch parameters of the pre-constructed grid model of the power grid digital twin to form a real-time power grid simulation condition.

3. The digital twin operation and maintenance platform in the power system according to claim 1, characterized in that: The generation of verification results and oscillation analysis reports are as follows: Analyze the power grid topology and current operating mode in real-time power grid simulation conditions; Based on the power grid topology, the protection range to be checked is determined and a check instruction is generated; Based on the current operating mode, determine the generator sets to be scanned and generate an oscillation scan command; According to the verification command, short-circuit current analysis and upper and lower limit comparison of the protection parameters of the power grid digital twin are performed. At the same time, according to the oscillation scan command, oscillation mode identification and damping characteristic evaluation are performed on the generator control parameters in the power grid digital twin. The results of short-circuit current analysis and the conclusions of setting value comparison are summarized to form the setting value verification conclusion. The results of oscillation mode identification and the conclusions of damping characteristic evaluation are integrated to form the stability evaluation conclusion. The setpoint verification conclusions and stability assessment conclusions are compiled into a structured document, and the verification results and oscillation analysis report are output.

4. The digital twin operation and maintenance platform in the power system according to claim 3, characterized in that: The process of determining the protection range to be verified and generating verification instructions involves identifying a set of protection devices that are electrically adjacent and have protection coordination relationships based on the power grid topology connection relationship, defining the protection device set as the protection range to be verified, and generating setting verification instructions for all protection devices within the protection range.

5. The digital twin operation and maintenance platform in the power system according to claim 3, characterized in that: The process of determining the generator sets to be scanned and generating oscillation scan commands is based on the generator output distribution and power flow of the grid interconnection line under the current operating mode. It identifies the dominant oscillation mode with a participation factor greater than a preset factor threshold, locates the generator sets dynamically coupled with the dominant oscillation mode, defines the generator sets to be scanned, and generates oscillation scan commands for the generator sets to be scanned.

6. The digital twin operation and maintenance platform in the power system according to claim 5, characterized in that: The participation factor is a modal analysis parameter that quantifies the degree of participation of the generator set in the dynamic response of the power oscillation mode.

7. The digital twin operation and maintenance platform in the power system according to claim 1, characterized in that: The specific generation coordination strategy is as follows. Extract protection setting adjustment items from the verification results, and extract oscillation suppression parameter optimization items from the oscillation analysis report; Based on the protection setting adjustment term and the oscillation suppression parameter optimization term, a combined strategy space is constructed in the power grid digital twin. The combined strategy space is then verified by transient stability simulation in conjunction with real-time power grid simulation conditions, and a strategy simulation set is generated. Based on the strategy simulation set, evaluate the protection action and damping level of each strategy in the combined strategy space, screen out strategies whose protection action and damping level both meet the feasible threshold, and combine them to generate a feasible strategy set. Select the strategy with the smallest adjustment range of the setpoint and the smallest adjustment range of the oscillation suppression parameter from the set of feasible strategies, and with the best suppression effect, as the coordination strategy.

8. The digital twin operation and maintenance platform in the power system according to claim 7, characterized in that: The generated strategy simulation set is as follows. In the digital twin of the power grid, the protection setting adjustment item and the oscillation suppression parameter optimization item are combined to generate a combined strategy space; Set the real-time power grid simulation conditions as the initial simulation state for each strategy in the combined strategy space; In the digital twin of the power grid, transient stability simulation is performed on each strategy in the combined strategy space in sequence to simulate the dynamic response of the digital twin power grid under preset disturbances and record the dynamic response data corresponding to each strategy. All dynamic response data are aggregated to generate a strategy simulation set.

9. The digital twin operation and maintenance platform in the power system according to claim 1, characterized in that: The feedback data verification of the coordination strategy based on the wide-area measurement array is as follows: Analysis of the protection setpoint adjustment scheme and oscillation suppression parameter setting scheme in the coordination strategy; Convert the protection setting adjustment scheme into a protection setting command, and convert the oscillation suppression parameter setting scheme into a control command; The protection setting command is sent to the target relay protection equipment, the control command is sent to the target new energy power station controller, and the command execution confirmation signal is received. Based on the command execution confirmation signal, the actual operation data of the power grid is collected through a wide-area measurement array to monitor the relay protection action and the power grid oscillation mode; The relay protection actions are compared with the expected protection objectives of the coordination strategy, and the grid oscillation modes are compared with the expected damping improvement objectives of the coordination strategy. Protection verification conclusions and damping improvement verification conclusions are generated respectively to complete the evaluation of the effectiveness of the coordination strategy.

10. The digital twin operation and maintenance platform in the power system according to claim 9, characterized in that: The instruction execution confirmation signal is a signal returned by the target relay protection equipment and the target new energy power station controller.

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