Smart grid state estimation methods, systems, and storage media based on topology analysis

Abstract

This invention discloses a smart grid state estimation method, system, and medium based on topology analysis. The method includes the following steps: constructing a substation state estimation model based on grid structure data; collecting measurement data; performing topology analysis on the measurement data to divide it into several topological islands; performing state estimation for each topological island based on the substation state estimation model; and inputting the mature data generated from the state estimation results into a real-time database. By using the above method to estimate the state of substations, this invention discloses a smart grid state estimation method based on topology analysis. By dividing topological islands and performing multiple measurements, it enables smart grid state estimation to have characteristics such as small network size, fast calculation speed, and reliable implementation. It solves the accuracy problem of redundant data within substations and sends the mature data generated from the substation state estimation to the dispatch center, providing efficient, reliable, and stable data for the entire network.

Description

Technical Field

[0001] This invention relates to the field of smart grid data security, and in particular to a smart grid state estimation method, system, and storage medium based on topology analysis. Background Technology

[0002] With the rapid development of smart grid technology and the continuous upgrading of power grid measurement devices, the power system has shifted from a traditional physical network to a cyber-physical network supported by power big data. The integration of the power grid and the data information network has also brought new challenges to the state assessment of the power system. State estimation of the power system is a core function of substation monitoring systems, a crucial link in the real-time data quality of the power system, and is related to the safe and stable operation of the power grid.

[0003] Currently, relatively mature data detection technologies have been provided in power systems. However, due to the special nature of smart grids, the main hidden danger lies in the fact that with the development of digitalization and intelligence in substations, the information uploaded by equipment in substations is gradually increasing. The highly redundant measurement configurations are not fully utilized, and bad data cannot be well identified, making it difficult to fundamentally solve the problem of the accuracy of state estimation basic data.

[0004] Therefore, it is necessary to provide a smart grid state estimation method based on topology analysis to solve the above-mentioned technical problems. Summary of the Invention

[0005] The main objective of this invention is to provide a smart grid state estimation method, system, and storage medium based on topology analysis, aiming to address how to improve the accuracy of the basic data for state estimation.

[0006] To achieve the above objectives, this invention proposes a smart grid state estimation method based on topology analysis, comprising the following steps:

[0007] Based on power grid structure data, a substation state estimation model is constructed;

[0008] Collect measurement data;

[0009] Perform topological analysis on the measurement data to identify several topological islands;

[0010] Perform state estimation for each topological island;

[0011] The mature data generated from the state estimation results is then entered into the real-time database.

[0012] Optionally, the specific steps for constructing the substation state estimation model are as follows:

[0013] Based on the power grid structure, different judgment rules are defined;

[0014] Set the corresponding expert database for each layer of judgment rules.

[0015] Optionally, the substation state estimation model includes three-phase power measurement, phase-by-phase power measurement, phase-by-phase current amplitude measurement, and phase-by-phase complex current measurement.

[0016] Optionally, the specific steps for modeling the measurement data using a topology algorithm are as follows:

[0017] Define nodes in topology analysis as topological islands;

[0018] Nodes in the topology that can be measured are defined as island nodes.

[0019] Optionally, the specific steps for performing state estimation for each topological island are as follows:

[0020] Perform topology error detection on topological islands;

[0021] Perform bad data detection on topological islands;

[0022] Optionally, the specific steps for detecting topological errors in topological islands are as follows:

[0023] The measurement data within each topological island is compared with the corresponding expert database.

[0024] If the criteria are met by the expert database, the identification is successful and the detection process ends.

[0025] If the expert database is not satisfied, the topological islands are redefined and topological error detection is performed until the detection termination condition is met.

[0026] Optionally, the measurement data includes model internal component judgment data, model inter-rule judgment data, model system rule judgment data, and historical cross-section judgment data.

[0027] Optionally, the specific steps for detecting bad data are as follows:

[0028] Generate measurements of bad data;

[0029] Compare the measured values ​​of bad data with the bad data scaling constant;

[0030] If the detected value of defective data is not greater than the defective data scale constant, the defective data detection termination condition is met, and the defective data detection ends.

[0031] If the detected value of defective data is greater than the defective data scale constant, the defective data is processed and defective data detection is repeated until the detection termination condition is met.

[0032] To address the aforementioned technical problems, this invention provides a smart grid state estimation system based on topology analysis, which runs on a processor or storage medium and is configured to execute the following instructions:

[0033] Construct a substation state estimation model;

[0034] Based on power grid structure data, a substation state estimation model is constructed;

[0035] Collect measurement data;

[0036] Perform topological analysis on the measurement data to identify several topological islands;

[0037] Based on the substation state estimation model, state estimation is performed for each topological island;

[0038] The mature data generated from the state estimation results is then entered into the real-time database.

[0039] To address the aforementioned technical problems, the present invention provides a storage medium, which is a computer-readable storage medium, characterized in that a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, it implements each step of the aforementioned smart grid state estimation method based on topology analysis.

[0040] In this invention, the power grid structure is first obtained through substation state estimation. A substation state estimation model is then constructed based on the existing power grid structure, involving the division and modeling of various modules within the substation and the formulation of judgment rules for each module, forming a corresponding expert database. Next, the data collected from the substation is measured using a data acquisition and monitoring control system and a power management unit. Then, based on the power grid structure, a topology algorithm is used to perform topology analysis on the measured data, dividing the data into several topological islands. These topological islands are nodes in the substation topology analysis, composed of zero-impedance switching branches and non-logic elements. Finally, state estimation is performed on each topological island to analyze the accuracy of the topology data within each island. Finally, the topology error detection results are entered into the real-time database. Specifically, the mature data generated after state estimation is written into the real-time database and uploaded to the dispatch center for use by other advanced services. The processing of error data involves error statistics and alarm delivery. The above method is used to perform state estimation of substations. This method has the characteristics of small network size, fast calculation speed, and reliable implementation. It solves the accuracy problem of redundant data in the substation and sends the mature data generated by the state estimation in the substation to the dispatch center, providing efficient, reliable and stable data for the entire network. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. 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 the structures shown in these drawings without creative effort.

[0042] Figure 1 This is a flowchart of a smart grid state estimation method based on topology analysis in one embodiment of the present invention;

[0043] Figure 2 This is a simplified network connection diagram of a substation in one embodiment of the present invention;

[0044] Figure 3 for Figure 2 A schematic diagram of a mid-topological island;

[0045] Figure 4 This is a flowchart illustrating the state estimation of topological islands in one embodiment of the present invention.

[0046] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0047] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0048] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0049] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0050] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0051] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0052] This invention proposes a smart grid state estimation method based on topology analysis, aiming to address how to improve the accuracy of the basic data for state estimation.

[0053] Reference Figure 1 The present invention proposes a smart grid state estimation method based on topology analysis, comprising the following steps:

[0054] S100: Construct a substation state estimation model based on power grid structure data;

[0055] S200: Collects measurement data;

[0056] S300: Performs topology analysis on measurement data to divide it into several topological islands;

[0057] S400: Based on the substation state estimation model, state estimation is performed for each topological island;

[0058] S500: Generates mature data from the state estimation results and inputs it into the real-time library.

[0059] In this embodiment, the power grid structure is first obtained through substation state estimation. Based on the existing power grid structure, a substation state estimation model is constructed, which involves dividing and modeling the various modules of the substation and formulating judgment rules for each module, forming its own expert database. Next, the data collected from the substation is measured through a data acquisition and monitoring control system and a power management unit. Then, based on the power grid structure, a topology algorithm is used to perform topology analysis on the measured data, dividing it into several topological islands. These topological islands are nodes in the substation topology analysis, composed of zero-impedance switching branches and non-logic elements. Furthermore, state estimation is performed on each topological island to analyze the accuracy of the topology data within each island. Finally, the topology error detection results are entered into the real-time database. Specifically, the mature data generated after state estimation is written into the real-time database and uploaded to the dispatch center for use by other advanced services. The processing of error data involves error statistics and alarm delivery. The above method is used to perform state estimation of substations. This method has the characteristics of small network size, fast calculation speed, and reliable implementation. It solves the accuracy problem of redundant data in the substation and sends the mature data generated by the state estimation in the substation to the dispatch center, providing efficient, reliable and stable data for the entire network.

[0060] Specifically, for step S100: A substation state estimation model is constructed based on the existing power grid structure. This involves dividing and modeling the various modules of the substation, formulating judgment rules for each module, and forming a corresponding expert database. The substation state estimation model includes three-phase power measurement, phase-by-phase power measurement, phase-by-phase current amplitude measurement, and phase-by-phase complex current measurement. Taking the three-phase measurement substation state estimation function as an example, the power grid model needs to provide three-phase voltage, three-phase current, and three-phase power models. Image data is primarily used for data acquisition and control monitoring system image configuration, displaying the model data and state estimation results in a configurable manner.

[0061] For step S200: Data from the substation is collected through the data acquisition and monitoring control system and the power management unit, and the collected data is measured.

[0062] For step S300: Based on the power grid structure, perform topology analysis on the measurement data to divide it into several topological islands. A topological island is a node in the substation topology analysis, composed of zero-impedance switch branches and non-logic components. Island nodes are the equipment nodes within the island that can provide measurement data, including generators, transformers, outgoing lines, capacitors, reactors, busbars, circuit breakers, isolating switches, and other remote signaling equipment. Specifically, based on the power grid structure, establish measurement models for the island nodes in the topological islands, mainly including the following aspects: three-phase power measurement, busbar measurement, circuit breaker measurement, isolating switch and grounding switch measurement, and power management unit measurement.

[0063] Among them, the three-phase power measurement includes ABC phase power measurement, ABC phase current amplitude measurement, ABC phase (line) voltage amplitude measurement, and ABC phase (line) complex voltage measurement.

[0064] Busbar measurements include the measurement of voltage amplitude of phases (lines) ABC and the measurement of combined voltage of phases (lines) ABC.

[0065] Circuit breaker measurements include three-phase power measurement, ABC phase power measurement, ABC phase current amplitude measurement, ABC phase switch remote signaling, and three-phase status remote signaling.

[0066] Measurements of isolating switches and grounding switches include remote signaling of ABC phase switches and remote signaling of three-phase status.

[0067] The power management unit measurements include phase-by-phase complex voltage measurement of all outgoing lines on the high-voltage side, phase-by-phase complex current measurement of all outgoing lines on the high-voltage side, three-phase power measurement of all outgoing lines on the high-voltage side, phase-by-phase complex voltage measurement of the high-voltage side of all main transformers, phase-by-phase complex current measurement of the high-voltage side of all main transformers, three-phase power measurement of the high-voltage side of all main transformers, phase-by-phase complex voltage measurement of the medium-voltage side of all main transformers, phase-by-phase complex voltage measurement of the low-voltage side of all main transformers, phase-by-phase complex current measurement of the medium-voltage side of each main transformer, phase-by-phase complex current measurement of the low-voltage side of each main transformer, three-phase power measurement of the medium-voltage side of each main transformer, phase-by-phase current measurement of the low-voltage side of each main transformer, phase-by-phase complex voltage measurement of each outgoing line on the medium and low voltage sides, and phase-by-phase complex current measurement of each outgoing line on the medium and low voltage sides.

[0068] The primary system and secondary system in a substation can also be divided separately. Specifically, the primary system refers to the primary equipment in the substation, such as transformers, switches, and surge arresters. The secondary system refers to the remote control used to send telemetry, remote signaling, and remote pulse signals and issue commands through these secondary protection / monitoring and control devices, i.e., the four remote information.

[0069] For step S400: Perform state estimation for each topology island and analyze the accuracy of the topology data in each topology island. Estimate the data within the topology island and compare it with the substation state estimation model. Specifically, firstly, the data transmitted from the topology island needs to be time-scaled according to the substation state estimation model. Then, perform state analysis on the zero-impedance switch branches in the topology. Finally, simultaneously perform topology analysis error detection and bad data detection and identification within the topology island. If errors are found, error statistics are performed; otherwise, the data is uploaded to the real-time database.

[0070] For step S500: The mature data generated from the state estimation results is entered into the real-time database and uploaded to the dispatch center for use by other advanced services. Specifically, if there are errors within the topology island, the erroneous results are also entered into the real-time database for subsequent detection and identification. The finally generated mature data is then sent to the dispatch center. This method of substation state estimation features small network size, fast calculation speed, and reliable implementation. It solves the accuracy problem of redundant data within the substation and sends the mature data generated from the substation state estimation to the dispatch center, providing efficient, reliable, and stable data for the entire network.

[0071] Furthermore, the specific steps for constructing the substation state estimation model are as follows:

[0072] Based on the power grid structure, different judgment rules are defined;

[0073] Set the corresponding expert database for each layer of judgment rules.

[0074] In this embodiment, different judgment rules are defined based on the existing power grid structure. Specifically, the judgment rules are divided into four levels: judgment of internal components within the model, judgment of rules between models, judgment of model system rules, and judgment of historical cross-sections. Modeling is performed by defining the above judgment rules, and then a corresponding expert database is set for each level of judgment rules for subsequent judgment comparison.

[0075] Based on the power grid structure, different judgment rules are defined for subsequent judgment of the collected data.

[0076] Each layer of decision rules will be assigned to a specific expert database. Specifically, the expert database will include the following:

[0077] When opening or closing the circuit breaker, both disconnectors on both sides of the switch must be in the closed position. Using the switch as the starting point for the search diagram, all grounding disconnectors along the reachable path should be in the open position.

[0078] When closing the circuit breaker, the load current should be 0; when opening the circuit breaker, there should be no current in the grounding switch.

[0079] When opening or closing the disconnecting switch, this compartment switch should be in the open position. Using the disconnector as the starting point for the search in the diagram, all grounding disconnectors on the reachable path should be in the open position.

[0080] When opening or closing the grounding disconnect switch, the switch in this compartment should be in the open position, and the disconnect switch should also be in the open position.

[0081] When the grounding switch is closed, all equipment on the reachable path should be in a "grounded" or "de-energized" state.

[0082] When operating disconnect switches and grounding switches, the load current value should be 0;

[0083] During remote operation, the device's communication status is normal, the remote and local locations are normal, and it is not in the designated location.

[0084] When the busbar-side disconnecting switch is closed, if it is a double busbar connection method and the bus tie circuit breaker and its two sides disconnecting switches are in the closed position, and the equipotential condition is met, the circuit breaker in this compartment can be in the closed position.

[0085] When closing the main transformer circuit breaker and disconnector, the order should be: high voltage side, medium voltage side, and low voltage side.

[0086] The main transformer circuit breaker and disconnecting switch should be opened in the order of low voltage side, medium voltage side, and high voltage side.

[0087] When the bypass disconnect switch is closed, the bypass circuit breaker should be in the open position, the bypass circuit breaker bay should be in hot standby status, and the bypass disconnect switches in other bays should be in the open position.

[0088] When the bypass isolating switch is tripped, the bypass circuit breaker should be in the open position.

[0089] The closing sequence for disconnecting switches is as follows: first close the power supply side, then close the load side.

[0090] The disconnecting switch should be opened in the following order: first open the load side, then open the power supply side.

[0091] Furthermore, the substation state estimation model includes three-phase power measurement, phase-by-phase power measurement, phase-by-phase current amplitude measurement, and phase-by-phase complex current measurement.

[0092] In this embodiment, the substation state estimation model includes three-phase power measurement, phase-by-phase power measurement, phase-by-phase current amplitude measurement, and phase-by-phase complex current measurement. Taking the three-phase measurement substation state estimation function as an example, the power grid model needs to provide three-phase voltage, three-phase current, and three-phase power models. The image data is more of an image configuration for data acquisition and control monitoring systems, which displays the model data and state estimation results in a configurable manner.

[0093] Furthermore, the specific steps for performing topology analysis on the measurement data are as follows:

[0094] Define nodes in topology analysis as topological islands;

[0095] Nodes in the topology that can be measured are defined as island nodes.

[0096] In this embodiment, a topological island is a node in the substation topology analysis, which is composed of zero-impedance switch branches and non-logic elements. The equipment nodes in the island that can provide measurement are defined as island nodes, including generators, transformers, outgoing lines, capacitors, reactors, busbars, circuit breakers, disconnectors, and other remote signaling equipment. Corresponding measurement and control devices need to be configured for outgoing lines, busbars, switches, and disconnectors, while power management unit devices also need to be configured for outgoing lines.

[0097] Reference Figure 2 and Figure 3 ,in Figure 2 This is a simplified network connection diagram for a substation. Figure 3 This is a schematic diagram of a topological island, where all non-logic elements become nodes in the topology analysis, and the connection lines containing circuit breakers are called switch branches, i.e., topological islands.

[0098] The device nodes that can provide measurement capabilities within an island are defined as island nodes. In this embodiment, the measurement and control device measures the analog quantities of the lines, transformers, and capacitors, specifically measuring the three-phase total power, phase power, phase circuit amplitude, and phase voltage amplitude of these nodes; it also measures the phase voltage amplitude of the busbar; and measures the three-phase total power, phase power, and phase current amplitude. The measurement and control device also performs digital measurements on switches and disconnectors, specifically measuring the three-phase overall closed and open states of switches, as well as the closed and open states of individual phases, and the three-phase overall closed and open states of disconnectors. Finally, the power management unit measures the three-phase total power, phase complex current, and phase complex voltage of the lines and transformers.

[0099] Reference Figure 4 The specific steps for state estimation of each topological island are as follows:

[0100] Perform topology error detection on topological islands;

[0101] Perform bad data detection on topological islands.

[0102] In this embodiment, the data transmitted from the topology island first needs to be time-scaled to the substation state estimation model. Then, the state analysis of the zero-impedance switch branch in the topology is performed. Finally, topology analysis error detection and bad data detection and identification are performed simultaneously within the topology island. If errors are found, error statistics are performed. If no errors are found, the data is uploaded to the real-time database.

[0103] Furthermore, the specific steps for topology error detection of topological islands are as follows:

[0104] The measurement data within each topological island is compared with the corresponding expert database.

[0105] If the criteria are met by the expert database, the identification is successful and the detection process ends.

[0106] If the expert database is not satisfied, the topological islands are redefined and topological error detection is performed until the detection termination condition is met.

[0107] In this embodiment, for topology error detection, the measurement data in each topology island needs to be compared with the corresponding expert database to identify the topology island. Specifically, the measurement data within the island is judged from four aspects: internal model component judgment data, inter-model rule judgment data, model system rule judgment data, and historical section judgment data. If all of these meet the expert database's judgment criteria, the identification is successful and the detection ends. If the expert database's judgment criteria are not met, the topology islands are re-divided, and topology error detection is performed again until the detection termination condition is met.

[0108] Furthermore, the measurement data includes model internal component judgment data, model inter-rule judgment data, model system rule judgment data, and historical cross-section judgment data.

[0109] In this embodiment, the judgment data for components within the model mainly includes the rules for each component under different operating modes compared to telemetry rules. The rule judgment data between models mainly includes establishing interdependent relationships between circuit breakers and switches in the system network based on their characteristics. Specifically, this includes the relationship between switch positions and related quantity measurements, and the relationship between switch positions and other switch positions.

[0110] Furthermore, the specific steps for detecting the problematic data are as follows:

[0111] Generate measurements of bad data;

[0112] Compare the measured values ​​of bad data with the bad data scaling constant;

[0113] If the detected value of defective data is not greater than the defective data scale constant, the defective data detection termination condition is met, and the defective data detection ends.

[0114] If the detected value of defective data is greater than the defective data scale constant, the defective data is processed and defective data detection is repeated until the detection termination condition is met.

[0115] In this embodiment, the measurement value of defective data is the ratio λ of the state estimate of the island node. Specifically, λ = Δh(x) / h(x), where h(x) is the state estimate of the island node, and Δh(x) is the difference between the state estimate and the measured value of the island node. A is set as a defective data size constant; in this embodiment, A = 0.1. When λ > A, it is determined to be defective data, and the defective data needs to be extracted and re-detected until the detection termination condition is met. When λ ≤ A, the defective data detection termination condition is met, and the defective data detection ends.

[0116] The basic tasks of power system state estimation include determining the node-branch connection relationship based on telemetry results; and estimating the power flow distribution of the system, i.e., node voltage, branch power, etc., based on telemetry results, with the results conforming to circuit laws.

[0117] The first task can be accomplished using a topology analysis program, while the second task is sometimes narrowly defined as power system state estimation. Its classic mathematical model is as follows:

[0118] min(zh(x))TW(zh(x))

[0119] stc(x) = 0

[0120] Where x is the state variable, namely the magnitude and phase angle of the node voltage, and z is the measured value. W is the weight matrix.

[0121] That is, x is used as the optimization variable, and the estimated value (h(x)) of a certain quantity can be calculated based on x. The objective function Δh(x) is the difference between the estimated value and the measured value using weighted least squares.

[0122] The bad data measurement value λ is calculated using the above formula, which is the ratio of the state estimates of the island nodes λ = Δh(x) / h(x).

[0123] Based on statistical experience, a bad data scaling constant A is set. In this embodiment, the bad data scaling constant A = 0.1. The bad data measurement value λ is compared with the bad data scaling constant A for judgment.

[0124] If the detected defective data value is not greater than the defective data scale constant, the defective data detection termination condition is met, and the defective data detection ends. The generated mature data from the detection results is entered into the real-time database and uploaded to the dispatch center for use by other advanced business processes.

[0125] If the detected defective data value exceeds the defective data scaling constant, the defective data is processed, and defective data detection is repeated until the detection termination condition is met. The processing of detected defective data involves error statistics and sending alarms.

[0126] To address the aforementioned technical problems, this invention provides a smart grid state estimation system based on topology analysis, which runs on a processor or storage medium and is configured to execute the following instructions:

[0127] Based on power grid structure data, a substation state estimation model is constructed;

[0128] Collect measurement data;

[0129] Perform topological analysis on the measurement data to identify several topological islands;

[0130] Perform state estimation for each topological island;

[0131] The mature data generated from the state estimation results is then entered into the real-time database.

[0132] In this embodiment, the power grid structure is first obtained through substation state estimation. Based on the existing power grid structure, a substation state estimation model is constructed, which involves dividing and modeling the various modules of the substation and formulating judgment rules for each module, forming its own expert database. Next, the data collected from the substation is measured through a data acquisition and monitoring control system and a power management unit. Then, based on the power grid structure, a topology algorithm is used to perform topology analysis on the measured data, dividing it into several topological islands. These topological islands are nodes in the substation topology analysis, composed of zero-impedance switching branches and non-logic elements. Furthermore, state estimation is performed on each topological island to analyze the accuracy of the topology data within each island. Finally, the topology error detection results are entered into the real-time database. Specifically, the mature data generated after state estimation is written into the real-time database and uploaded to the dispatch center for use by other advanced services. The processing of error data involves error statistics and alarm delivery. The above method is used to perform state estimation of substations. This method has the characteristics of small network size, fast calculation speed, and reliable implementation. It solves the accuracy problem of redundant data in the substation and sends the mature data generated by the state estimation in the substation to the dispatch center, providing efficient, reliable and stable data for the entire network.

[0133] To address the aforementioned technical problems, the present invention also provides a storage medium, which is a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the various steps in the aforementioned smart grid state estimation method based on topology analysis.

[0134] Computer software products are stored in a storage medium and include several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0135] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A smart grid state estimation method based on topology analysis, characterized in that, Includes the following steps: Based on power grid structure data, a substation state estimation model is constructed; Collect measurement data; Perform topological analysis on the measurement data to identify several topological islands; Based on the substation state estimation model, state estimation is performed for each topological island; The mature data generated from the state estimation results is then entered into the real-time database. The specific steps for constructing the substation state estimation model are as follows: Based on the power grid structure, different judgment rules are defined; Set the corresponding expert database for each layer of judgment rules; The specific steps for performing topology analysis on the measurement data are as follows: Define nodes in topology analysis as topological islands; Nodes in the topology that can be measured are defined as island nodes; Based on the power grid structure, a measurement model is established for the island nodes in the topological island. The measurement model includes three-phase power measurement, bus measurement, circuit breaker measurement, isolating switch and grounding switch measurement, and power management unit measurement. The aforementioned smart grid state estimation method based on topology analysis is characterized in that the specific steps for state estimation of each topological island are as follows: Perform topology error detection on topological islands; Perform bad data detection on topological islands; The specific steps for detecting topological errors in topological islands are as follows: The measurement data within each topological island is compared with the corresponding expert database. If the criteria are met by the expert database, the identification is successful and the detection process ends. If the expert database is not satisfied, the topological islands are redefined and topological error detection is performed until the detection termination condition is met.

2. The smart grid state estimation method based on topology analysis according to claim 1, characterized in that, The substation state estimation model includes three-phase power measurement, phase-by-phase power measurement, phase-by-phase current amplitude measurement, and phase-by-phase complex current measurement.

3. The smart grid state estimation method based on topology analysis according to claim 1, characterized in that, The measurement data includes data on the judgment of internal components of the model, data on the judgment of rules between models, data on the judgment of rules of the model system, and data on the judgment of historical cross sections.

4. The smart grid state estimation method based on topology analysis according to claim 1, characterized in that, The specific steps for detecting bad data are as follows: Generate measurements of bad data; Compare the measured values ​​of bad data with the bad data scaling constant; If the detected value of defective data is not greater than the defective data scale constant, the defective data detection termination condition is met, and the defective data detection ends. If the detected value of defective data is greater than the defective data scale constant, the defective data is processed and defective data detection is repeated until the detection termination condition is met.

5. A smart grid state estimation system based on topology analysis, characterized in that, Running on a processor or storage medium, it is configured to execute the following instructions: Based on power grid structure data, a substation state estimation model is constructed; Collect measurement data; Perform topological analysis on the measurement data to identify several topological islands; Perform state estimation for each topological island; The mature data generated from the state estimation results is then entered into the real-time database. The specific steps for constructing the substation state estimation model are as follows: Based on the power grid structure, different judgment rules are defined; Set the corresponding expert database for each layer of judgment rules; The specific steps for performing topology analysis on the measurement data are as follows: Define nodes in topology analysis as topological islands; Nodes in the topology that can be measured are defined as island nodes; Based on the power grid structure, a measurement model is established for the island nodes in the topological island. The measurement model includes three-phase power measurement, bus measurement, circuit breaker measurement, isolating switch and grounding switch measurement, and power management unit measurement. The aforementioned smart grid state estimation method based on topology analysis is characterized in that the specific steps for state estimation of each topological island are as follows: Perform topology error detection on topological islands; Perform bad data detection on topological islands; The specific steps for detecting topological errors in topological islands are as follows: The measurement data within each topological island is compared with the corresponding expert database. If the criteria are met by the expert database, the identification is successful and the detection process ends. If the expert database is not satisfied, the topological islands are redefined and topological error detection is performed until the detection termination condition is met.

6. A storage medium, said storage medium being a computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the various steps of the smart grid state estimation method based on topology analysis as described in any one of claims 1 to 4.

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