Fault analysis and rapid verification method of smart substation considering information reliability

Abstract

The present invention relates to the technical field of substations, and in particular to an intelligent substation fault analysis and rapid verification method considering information reliability, comprising the following steps: S1, data generation and collection: regularly recording the operating parameters of a primary device; S2, communication network structure and data transmission: adopting a redundant communication network structure of three layers and two networks and strengthening link reliability by protecting the redundant structure of the AB set; S3, fault information analysis and processing: using a fast analysis SCD file to generate and update the network topology of the substation, thereby monitoring the equipment status and identifying fault signals, and generating corresponding alarms; S4, fault response and operation and maintenance monitoring: operation and maintenance personnel use the SCADA system and fault information to analyze the location of the faulty equipment, and realize real-time monitoring and fault processing of the entire substation. The present invention improves the ability of the substation system to discover, analyze and process faults.

Description

Technical Field

[0001] The present invention relates to the technical field of substations, and in particular to a fault analysis and rapid verification method for an intelligent substation taking information reliability into consideration. Background Art

[0002] Substations are an important part of the power information-physical fusion system. They have both ICT-based computer network facilities and a large number of physical equipment in the primary and secondary systems of the power grid. The network security of substations is very important for ensuring the stable operation of the power system. The secondary system of smart substations is an important part of monitoring the status of smart substations, ensuring safe and stable operation of substations, and adjusting the operation mode. It coordinates the information of the entire substation and plans to monitor faults or abnormal conditions in the power system, including sending alarm signals or directly isolating and removing the faulty parts. It is of great significance to the safe operation of the entire power grid. While smart substations provide convenience to staff, the protection system will also generate massive multi-dimensional data when a fault occurs. The validity and authenticity of the data are low, and it is difficult for maintenance personnel to diagnose specific faults in a short time.

[0003] Compared with ordinary substations, the connection between the protection system equipment of the smart substation no longer relies on hard-wired connections such as optical cables, but relies on the "three-layer two-network" network architecture of the IEC61850 protocol to achieve communication between the equipment. Therefore, it is more difficult to identify when the virtual link connecting the equipment fails. At the same time, there are many types of faults in the secondary system of the smart substation. The accuracy of judging the specific fault only by the information provided by the protection and measurement and control device is low. With the rapid development of communication networks, the forms of network attacks are becoming increasingly complex. The protection system, as an important component for maintaining the safe operation of substations, has become the primary target of attackers to carry out network attacks on substations. They often interfere with the normal operation of the protection system through network attacks such as false data injection, data tampering, and vulnerability exploitation, affecting the operation and maintenance personnel and the primary system equipment to make wrong responses, causing the substation and even the entire power system to lose power. Therefore, after the smart substation protection system generates fault information, it is necessary to quickly verify the authenticity of the data of the fault information throughout its life cycle to provide convenient conditions for the staff's judgment and maintenance.

[0004] The present invention establishes a multi-dimensional data security assessment system for the substation based on the secondary circuit of the substation, pre-detects the secondary system data before passing through the secondary circuit, considers the primary and secondary system characteristics and network structure of the substation, quickly locates the fault information in the station and verifies its reliability, which is convenient for the substation operation and maintenance personnel to clarify the cause of the fault and respond quickly and effectively, prevents direct harm and potential risks caused by failure of secondary system equipment and network attacks, and enhances the resilience of the substation system. Summary of the invention

[0005] Based on the above objectives, the present invention provides a smart substation fault analysis and rapid verification method taking information reliability into consideration.

[0006] The intelligent substation fault analysis and rapid verification method considering information reliability includes the following steps:

[0007] S1, data generation and collection: regularly record the operating parameters of primary equipment, including transformer voltage and loop current, and perform preliminary processing and local storage of the operating parameters through process layer equipment. At the same time, establish a multi-dimensional data security detection and evaluation system to ensure the authenticity and accuracy of the data;

[0008] S2, communication network structure and data transmission: adopt a three-layer two-network redundant communication network structure and enhance link reliability by protecting the redundant structure of AB sets;

[0009] S3, fault information analysis and processing: Use fast analysis of SCD files to generate and update the substation network topology, thereby monitoring equipment status and identifying fault signals, and generating corresponding alarms;

[0010] S4, Fault response and operation and maintenance monitoring: Operation and maintenance personnel use the SCADA system and fault information to analyze the location of faulty equipment and achieve real-time monitoring and fault handling of the entire substation.

[0011] Furthermore, the data generation and collection in S1 includes:

[0012] S11, data acquisition: During the operation of the smart substation, the secondary circuit records the operating parameters of the primary equipment according to the set measurement cycle. The operating parameters are the basis for monitoring and controlling the primary circuit;

[0013] S12, data processing and uploading: The collected operating parameters are processed by the merging unit and the intelligent terminal at the process layer. After preliminary analysis and integration, the operating parameters are transmitted through the protection measurement and control device and uploaded to the station control layer to provide real-time monitoring and control information for the operation and maintenance personnel;

[0014] S13, Multi-dimensional data security detection and evaluation: Establish a multi-dimensional data security detection and evaluation system to ensure the authenticity and validity of the operating parameters provided by the process layer. After obtaining the operating parameters, the equipment performs local data analysis and storage, and pre-processes the operating parameters;

[0015] S14, coupling data analysis: coupling analysis is performed on the operation data of the substation secondary system to analyze whether the same type of operation data is within the specified range, and to check the coupling relationship between different types of operation data. If the coupling indicators are abnormally correlated, it indicates that there is a fault between the primary equipment and the secondary system of the substation.

[0016] Furthermore, the multi-dimensional data security detection and evaluation in S13 includes:

[0017] S131, establish a multi-dimensional data security assessment system: Based on the quality, characteristics and distribution characteristics of the operating data of the secondary system of the smart substation, establish a multi-dimensional data security assessment system covering data accuracy, completeness, consistency, timeliness, correctness and redundancy to achieve pre-processing and reliability verification of operating parameters in the substation;

[0018] S132, data preprocessing and evaluation: preprocess the operating parameters within the collection period, filter out the information used as the basis for data evaluation, reduce the data size by dividing the data set and clustering it, while ensuring the integrity of the information, and calculate the preprocessed operating parameters according to the multidimensional data security evaluation system;

[0019] S133, data consistency calculation: using the methods and rules of the substation protection measurement and control device, the consistency calculation of the operation data is performed, the consistency of the operation data is judged by calculating the deviation degree of the operation data, the consistency detection of the same type of operation data and the different type of operation data is performed, and the abnormal operation data is identified and reported;

[0020] S134, fault information processing and uploading: If the operating parameters within the collection period do not meet the reliability verification of the multi-dimensional data security assessment system, it is considered that a substation fault has occurred, and the verified fault information is directly sent to the station control layer through optical fiber. At the same time, the local backup of the operating parameters is used as the basis for traceability and uploaded to the substation communication network through the merging unit and the intelligent terminal.

[0021] Furthermore, the consistency detection of the same type of operation data includes:

[0022] Dataset division: The running data is divided into data sets P. Data set P has n different types of running data M = {M1, M2, ...M n},M n Contains N samples m i ={m i1 ,m i2 ,...m iN};

[0023] Consistency test: All running data in the data set are fitted by the least squares method through a scatter plot, and then the fitted prediction value is used to verify the offset value of the same type of running data. The offset sequence B after fitting i The calculation formula is:

[0024]

[0025] Among them, y i is the i-th fitted value of the same type of running data, yi ′ is the i-th predicted value of the same type of running data;

[0026] Abnormal detection and reporting: Based on the stable operation requirements of the substation, the maximum deviation threshold F is set c , if |B i |>F c , the operating data is considered abnormal. After detecting all the operating data in the data set, the operating data of the fault is integrated and evaluated, and the fault-related information is uploaded to the substation network.

[0027] Furthermore, the consistency detection of the non-similar operation data includes:

[0028] Regression equation establishment: Select a certain type of running data in the data set as the dependent variable v i , other types of operation data are listed as independent variables x ki , establish a regression equation to qualitatively detect the degree of deviation of running data, and the calculation formula is:

[0029]

[0030] Among them, β0 is the random error, β1,β2,…,β p is the regression coefficient;

[0031] Consistency detection and evaluation: The predicted value of the dependent variable is solved by the regression equation, and the maximum deviation threshold F is set based on the stable operation requirements of the substation. z , if |B i |>F z , the operating data is considered abnormal. After detecting all the operating data in the data set, the operating data of the fault is integrated and evaluated, and the fault-related information is uploaded to the substation network.

[0032] Furthermore, the communication network structure and data transmission in S2 include:

[0033] S21, establishment of redundant communication network structure: the smart substation adopts a three-layer two-network redundant communication network structure to monitor network devices and information flows, and upload fault information to the station control layer in a timely manner;

[0034] S22, protect the redundant structure of AB sets: By protecting the redundant structure of AB sets, the reliability of the communication link is enhanced. The process layer acquisition device pre-processes the operating parameters. After the electronic transformer data is safety verified, the SV sampling message is output to the process layer SV switch through two sets of independent merging units;

[0035] S23, independent data collection and control: using two sets of independent intelligent terminals, independently collecting and controlling primary equipment (such as circuit breakers, switches, etc.), the operating parameters enter the process layer network through the process layer switch, and the process layer network uses GOOSE network and SV network to operate independently to improve the stability of the communication link;

[0036] S24, data transmission between the bay layer and the station control layer: the bay layer equipment (relay protection device and measurement and control device) adopts a dual configuration, which connects to the primary equipment switch quantity signals uploaded by the process layer network A and network B and the analog signals of the continuously changing physical quantities (such as voltage, current, power, etc.) in the substation, and uploads them to the station control layer through the station control layer switch. The station control layer MMS network adopts a dual configuration, and the bay layer equipment provides two Ethernet ports connected to the MMSA network and the MMSB network respectively;

[0037] S25, data presentation and monitoring: The substation operation data is presented to the station control layer monitoring host through the secondary system, and the operation and maintenance personnel can realize real-time monitoring and fault handling.

[0038] Furthermore, the fault information analysis and processing in S3 includes:

[0039] S31, fast parsing of SCD file: Parse the SCD file to obtain the status and logical relationship between the primary equipment and the secondary system of the substation, including the SV and GOOSE message publishing and subscription relationship between electronic devices (IEDs), the interaction and logical connection information of the input and output virtual terminals of electronic devices (IEDs);

[0040] S32, generate network topology: generate a network topology with substation equipment as nodes according to the parsed SCD file, parse the communication link information, update the fault information status, and if the communication link is abnormal or interrupted, generate a new network topology and prompt an alarm signal;

[0041] S33, faulty equipment integration: Analyze SV or GOOSE message information, and determine the faulty equipment with interrupted secondary system network communication through virtual terminal connections between substation equipment;

[0042] S34, fault information analysis and reporting: Use the SCD file to analyze the fault-related equipment, calculate the location probability of the faulty equipment, upload the fault location prediction and alarm information to the monitoring host, and record the relay protection action and automatic fault handling information for reference by the operation and maintenance personnel.

[0043] Furthermore, the integration of faulty equipment in S33 includes:

[0044] S331, initial data set: Use the SCD file to analyze all substation equipment related to the fault information to form an initial data set E of the equipment related to the fault information, expressed as:

[0045] E={e1,e2,e3,...,e n};

[0046] S332, construct a communication relationship matrix: construct a communication relationship matrix M, define a communication relationship function f(e i ,e j ) is the device e of this fault event i With equipment j The communication association between them is calculated as follows:

[0047]

[0048] S333, constructing a correlation data set: The correlation data set reflects the physical connection and logical connection relationship between devices. Based on the substation secondary system network structure and fault information, the location probability of the faulty device is obtained. The calculation formula is:

[0049] M n =[f(e n ,e1)f(e n ,e2)...f(e n ,e n )];

[0050] S334, generating a data set after the failure: the data set after the failure is expressed as:

[0051] P=[f1,f2,...f n ] T ;

[0052] Among them, the fault information includes equipment e n If there is no correlation in the data, the corresponding f value is 1, and if there is no correlation in the data, it is 0.

[0053] Furthermore, the calculation formula for the location probability of the faulty device is:

[0054] S n =M n ×P;

[0055] Among them, S n The larger the value of is, the more likely the fault is caused by device n.

[0056] Furthermore, the fault response and operation and maintenance monitoring in S4 include:

[0057] S41, monitoring operation: Operation and maintenance personnel use the substation SCADA system operation terminal composed of monitoring host and telecontrol to realize the monitoring of the whole substation operation status;

[0058] S42, Fault detection and initial response: When the results of the multi-dimensional data safety detection and evaluation system at the process layer are abnormal or fault information appears at the station control layer, the operation and maintenance personnel analyze the fault and deal with it in a timely manner;

[0059] S43, process layer data exception processing: When the process layer operating parameters are abnormal, the fault operating parameters are presented to the monitoring host through the optical fiber directly connected to the station control layer to assist the operation and maintenance personnel in determining the cause of the fault;

[0060] S44, comprehensive fault analysis: when fault information appears at both the process layer and the station control layer, and the abnormal data matches the fault information, it is determined that the primary equipment has a fault;

[0061] S45, pre-detection data abnormality processing: when the process layer pre-detection operating parameters are abnormal, and the station control layer does not have fault information, it is judged that the primary equipment of the substation is faulty and is attacked by the external network to cover up the primary equipment fault;

[0062] S46, communication link fault processing: when the process layer data is normal, but the station control layer has fault information, it is determined that the substation secondary system communication link has a fault;

[0063] S47, fault repair and recovery: After repairing the secondary system fault, adjust the primary equipment switch quantity to normal state until the primary equipment and secondary system of the substation are stable and complete the manual maintenance.

[0064] Beneficial effects of the present invention:

[0065] The present invention adds a pre-detection step of security assessment of underlying measurement data on the basis of the existing substation secondary system data processing method, which not only ensures the reliability of underlying measurement data, but also provides a basis for fault information tracing verification, thereby improving the ability of the substation system to discover, analyze and handle faults.

[0066] The present invention ensures the reliability of the substation secondary system data throughout its entire life cycle, selects two key nodes, data generation and data processing, and considers the interactive relationship between the substation primary and secondary systems when analyzing system information, while clearly isolating the substation primary and secondary system faults, which helps operation and maintenance personnel determine the source of the fault, make an effective response in a timely manner, and prevent the fault from spreading and causing serious threats to the power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only for the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0068] Figure 1 Schematic diagram of a multi-dimensional data security assessment system for a smart substation according to an embodiment of the present invention;

[0069] Figure 2 A schematic diagram of a network interaction structure of a smart substation according to an embodiment of the present invention;

[0070] Figure 3 The present invention is a schematic diagram of a substation secondary system fault information detection and rapid verification process according to an embodiment of the present invention. DETAILED DESCRIPTION

[0071] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0072] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0073] like Figure 1-Figure 3 As shown, the intelligent substation fault analysis and rapid verification method considering information reliability includes the following steps:

[0074] Step 1: During the operation of the smart substation, the secondary circuit records the operating parameters of the primary equipment according to the set measurement cycle, that is, the generation and collection of data, mainly including data information such as transformer voltage and loop current. After the measurement data is processed by the merging unit and the intelligent terminal at the process layer, the communication equipment will finally send the effective information to the station control layer through the protection, measurement and control devices, etc., and present it to the operation and maintenance personnel to realize the monitoring and control of the primary circuit. The authenticity of the data and the validity of the information provided by the process layer are the prerequisites for the safe operation of the substation. Therefore, the present invention proposes that the process layer equipment quickly perform local data analysis and storage after obtaining the measurement data, establish a multi-dimensional data security detection and evaluation system to ensure the authenticity and accuracy of the data source, and pre-process the data while the primary and secondary systems interact, so as to improve the efficiency of substation fault detection.

[0075] The data types of the secondary system of the substation are complex. The same type of data has a unified format and a specified range. Different types of data also have coupling associations. The measuring device can make a simple analysis of single data to determine whether it is within the normal range. However, the existing smart substation secondary system has not yet effectively analyzed the underlying coupled measurement data. Adding process layer related data for coupling analysis and processing can more accurately mine system faults. If there is an abnormal correlation between coupling indicators such as current and capacity, that is, a single indicator is within its normal range, but its coupling indicator is significantly deviated from the normal state, it can be diagnosed that the primary and secondary systems of the substation have hidden faults, which may be caused by abnormal measurement instruments, illegal data tampering, etc. The method for the multi-dimensional data security assessment system of the substation is as follows:

[0076] 1. According to the data quality, data characteristics and distribution characteristics of the secondary system of smart substation, a multi-dimensional data security assessment system covering data accuracy, completeness, consistency, timeliness, correctness and redundancy is established. Figure 1 As shown in the figure, it can realize the rapid pre-processing and reliability verification of the measurement data in the station, and improve the transmission efficiency and stability of the secondary system information in the substation network.

[0077] 2. Preprocess the measurement data within the collection period, select valid information as the basis for data evaluation, reduce the data size by dividing the data set and clustering it, while ensuring the integrity of the information, and then calculate the preprocessed data according to the security assessment method.

[0078] 3. The methods and rules used for data calculation and analysis at the process level are mostly similar to the principles of substation protection and measurement and control devices, but data consistency calculations are added to ensure the local data reliability of the measurement data.

[0079] The consistency of the data is determined by calculating the degree of data deviation. For the determination of similar data, when the substation is operating normally, there will not be excessive data fluctuations between the same type of data. If the deviation degree of adjacent measured data is low, the data is considered to be consistent and meets the conditions for safe operation of the system. Non-similar data with coupling relationships should maintain logical consistency and have a certain association relationship. If the adjacent values ​​of the coupled data produce a large change in the logical relationship, the data is considered to deviate from the normal value and the fault needs to be reported. Suppose there are n different types of data M={M1,M2,...M n}, where M n Contains N samples m i ={m i1 ,m i2 ,...m iN}.

[0080] For consistency check of the same type of data, all the data in the data set are fitted by the least squares method through the scatter plot, and then the fitted prediction value is used to verify the offset value of the same type of data. The offset sequence after fitting is B i for:

[0081]

[0082] Among them, y i is the i-th fitted value of this type of data, y i ′ is the i-th predicted value of this type of data.

[0083] Based on the requirement of stable operation of substation, the maximum deviation threshold F is set. c , if |B i |>F c , then the measured value is considered abnormal. After testing all the data in the data set, the fault data is integrated and evaluated, and all the fault-related information is uploaded to the substation network.

[0084] For consistency detection of non-similar data, the data sets with coupled correlation are put into one data set for research, and the prediction value of the regression equation and the interpolation of the true value are detected to see whether they exceed the maximum row threshold. Select a certain type of data in the data set as the dependent variable v i , the other columns are independent variables x ki , establish a regression equation to qualitatively detect the degree of column data deviation. The specific formula is as follows:

[0085]

[0086] Among them, β0 is the random error, β1,β2,…,β p is the regression coefficient.

[0087] Solve the predicted value of the dependent variable by the regression equation, and then use formula (1) to obtain the offset sequence B of this type of data i , based on the stable operation requirements of the substation, set the maximum deviation threshold F z , if |B i |>F z , then the measured value is considered abnormal. After testing all the data in the data set, the fault data is integrated and evaluated, and all the fault-related information is uploaded to the substation network.

[0088] 4. If the measured data within the collection period does not meet the reliability verification of any dimension, it is considered that the substation has a fault. The fault information detected this time is processed and sent directly to the station control layer through optical fiber, which is conducive to the control end to take effective response in time and play a certain early warning role. At the same time, the local data backup is used as the basis for tracing the source, and then uploaded to the substation communication network through the merging unit and the intelligent terminal.

[0089] Step 2: The smart substation adopts a "three-layer two-network" redundant communication network structure to ensure the reliability of secondary system information. The substation communication network structure is as follows: Figure 2 As shown. The number of secondary devices is huge and closely connected. When abnormal operation information is detected in the station, multiple devices with information related to it will be affected and send out alarm signals. While ensuring the system's timely response to faults, the complex network structure also puts forward higher requirements on the reliability of the communication link, so that the fault information is not disturbed during the communication process. Therefore, it is necessary to ensure the stability of the communication link, characterize the characteristic information of the secondary system fault by monitoring the network device and information flow, and upload the fault information to the station control layer in a timely and accurate manner.

[0090] The "three-layer two-network" structure is the basis for realizing comprehensive automation of the secondary system of the substation. The redundant structure of the protection AB set is adopted to enhance the reliability of the communication link. The process layer acquisition device pre-processes the data. After the safety verification in step 1, the electronic transformer data passes through two independent merging units, and outputs the SV sampling message specified in the IEC61850-9-2 standard to the process layer SV switch. Two independent intelligent terminals are used to independently collect the information of the primary equipment (such as circuit breakers, switches, etc.) of the corresponding interval and realize the control function. Then the data enters the process layer network of the intelligent substation through the process layer switch. The process layer network adopts the GOOSE network and the process layer SV network to be independent and dualized. When one of the networks fails, it does not affect the independent operation of the other network, so as to improve the communication stability.

[0091] The equipment at the bay layer mainly includes relay protection devices and measurement and control devices, both of which are configured in a dual configuration to form two independent protection and measurement and control coordination circuits without direct electrical connection. They are connected to the switch and analog signals sent from the process layer network A and B respectively, and uploaded to the station control layer through the corresponding station control layer switch. The station control layer MMS network adopts a dual configuration, and the bay layer equipment provides two Ethernet ports connected to the MMSA network and the MMSB network respectively. Finally, the substation operation data will be presented to the station control layer monitoring host through the secondary system, and the operation and maintenance personnel will realize real-time monitoring, operation, control and fault handling of the substation based on the reported information. Therefore, under the premise that the measurement device collects and generates data accurately in step 1, the data reliability after the communication link is high, and the operation and maintenance personnel monitor the operation status of the entire station through the station control layer monitoring host.

[0092] Step 3: To ensure that the station control layer receives the switch and analog signals provided by the secondary system in a timely and accurate manner, and locates and handles substation faults in a timely manner, the received SCD file needs to be quickly parsed. The SCD file can reflect the status and logical relationship of the primary and secondary devices of the substation, mainly including the SV / GOOSE message publishing and subscription relationship between intelligent electronic devices (IEDs), IED input and output virtual terminals, and other information describing the device information interaction and logical connection relationship.

[0093] By parsing the SCD file under normal operation of the substation, a network topology with substation equipment as nodes is generated, and the communication link information is parsed. The node element value is updated with the received fault information status. If the link information is abnormal, an alarm signal will be prompted. Link interruption or abnormality is equivalent to link disappearance, and a new network topology will be generated. Substation equipment is interconnected with multiple other devices through virtual terminals. By analyzing SV or GOOSE message information and finding secondary system network communication interruption information, the relative probability gradient of the fault location can be preliminarily determined to improve the efficiency of fault location. When the station control layer receives the fault information, it uses the SCD file to analyze all devices related to the fault information to form the initial data set E of the devices related to the fault information:

[0094] E={e1,e2,e3,...,e n} (3)

[0095]

[0096] where f(e1,e n ) is the fault event device e1 and device e n If device e1 receives e n , then f(e1,e n ) value is 1, if there is no communication association, then device e n The device association data set is:

[0097] M n =[f(e n ,e1)f(e n ,e2)...f(e n ,e n )](5)

[0098] The associated data set reflects the physical and logical connection relationships between devices and is the information association of the substation secondary system network. Based on the network's own structure and specific fault information, the location probability of the faulty device can be obtained.

[0099] The data set after the failure is:

[0100] P=[f1,f2,...f n ]T (6)

[0101] If the fault information contains device e n If there is no data association, the corresponding f value is 1, and if there is no data association, it is 0. The probability S of the location of the faulty device n for:

[0102] S n =M n ×P (7)

[0103] S n The larger the value is, the more likely the fault is caused by device n.

[0104] After the fault location is preliminarily determined, the fault location prediction and fault alarm information are uploaded to the monitoring host, and the substation status information after the relay protection action and automatic fault handling is recorded in detail to provide a reference for operation and maintenance personnel to analyze the cause of the fault and control commands.

[0105] Step 4: The operation and maintenance personnel use the substation SCADA system operation terminal composed of the monitoring host and telecontrol to realize the monitoring of the whole substation operation status. When the primary and secondary systems of the substation are operating normally, no manual operation is required. When the process layer data security assessment result in step 1 is abnormal or the station control layer has fault information, the operation and maintenance personnel need to analyze the specific fault and deal with it in time to reduce the adverse impact of the fault on the power system. The complete substation secondary system fault information detection and rapid verification process is as follows Figure 3 shown.

[0106] When the process layer data measurement value is abnormal, the fault data is quickly presented to the monitoring host through the optical fiber directly connected to the station control layer to assist the operation and maintenance personnel in determining the cause of the fault. When fault information appears in both the process layer and the station control layer, and the abnormal data matches the fault information, it can be preliminarily determined that the primary equipment has failed. The process layer data security assessment results are used as the basis for fault tracing and provide a reference for the operation and maintenance personnel to determine the specific fault; when the process layer pre-detection data is abnormal, but the station control layer does not have fault information, it can be preliminarily determined that the substation primary system has failed, and the primary system failure is covered up by external network attacks. It is necessary to further determine the cause of the fault and repair it in time in combination with the status of the intelligent terminal, system message proofreading, and the status of the primary and secondary equipment; when the process layer data is normal, but the station control layer has fault information, it can be preliminarily determined that the communication link of the substation secondary system has failed. It is necessary to find the fault point in combination with the whole process information, and check whether the relay protection has malfunctioned or refused to operate. After repairing the secondary system fault, the switch quantity should be adjusted to the normal state in time until the primary and secondary systems of the substation are stable and the manual maintenance is completed.

[0107] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention is limited to these examples. Under the concept of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

[0108] The present invention is intended to cover all such substitutions, modifications and variations that fall within the broad scope of the claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A smart substation fault analysis and rapid verification method considering information reliability, characterized in that: The following steps are involved: S1, data generation and collection: regularly record the operating parameters of primary equipment, including transformer voltage and loop current, and perform preliminary processing and local storage of the operating parameters through process layer equipment. At the same time, establish a multi-dimensional data security detection and evaluation system to ensure the authenticity and accuracy of the data; S2, communication network structure and data transmission: adopt a three-layer two-network redundant communication network structure and enhance link reliability by protecting the redundant structure of AB sets; S3, fault information analysis and processing: Use fast analysis of SCD files to generate and update the substation network topology, thereby monitoring equipment status and identifying fault signals, and generating corresponding alarms; S4, Fault response and operation and maintenance monitoring: Operation and maintenance personnel use the SCADA system and fault information to analyze the location of faulty equipment and achieve real-time monitoring and fault handling of the entire substation; The data generation and collection in S1 includes: S11, data acquisition: During the operation of the smart substation, the secondary circuit records the operating parameters of the primary equipment according to the set measurement cycle. The operating parameters are the basis for monitoring and controlling the primary circuit; S12, data processing and uploading: The collected operating parameters are processed by the merging unit and the intelligent terminal at the process layer. After preliminary analysis and integration, the operating parameters are transmitted through the protection measurement and control device and uploaded to the station control layer to provide real-time monitoring and control information for the operation and maintenance personnel; S13, Multi-dimensional data security detection and evaluation: Establish a multi-dimensional data security detection and evaluation system to ensure the authenticity and validity of the operating parameters provided by the process layer. After obtaining the operating parameters, the equipment performs local data analysis and storage, and pre-processes the operating parameters; S14, coupling data analysis: coupling analysis and processing of the operation data of the substation secondary system, analyzing whether the same type of operation data is within the specified range, and checking the coupling relationship between different types of operation data. If the coupling index is abnormally correlated, it indicates that there is a fault between the primary equipment and the secondary system of the substation; The multi-dimensional data security detection and assessment in S13 includes: S131, establish a multi-dimensional data security assessment system: Based on the quality, characteristics and distribution characteristics of the operating data of the secondary system of the smart substation, establish a multi-dimensional data security assessment system covering data accuracy, completeness, consistency, timeliness, correctness and redundancy to achieve pre-processing and reliability verification of operating parameters in the substation; S132, data preprocessing and evaluation: preprocess the operating parameters within the collection period, filter out the information used as the basis for data evaluation, reduce the data size by dividing the data set and clustering it, while ensuring the integrity of the information, and calculate the preprocessed operating parameters according to the multidimensional data security evaluation system; S133, data consistency calculation: using the methods and rules of the substation protection measurement and control device, the consistency calculation of the operation data is performed, the consistency of the operation data is judged by calculating the deviation degree of the operation data, the consistency detection of the same type of operation data and the different type of operation data is performed, and the abnormal operation data is identified and reported; S134, fault information processing and uploading: If the operating parameters within the collection period do not meet the reliability verification of the multi-dimensional data security assessment system, the substation is deemed to have a fault, and the verified fault information is directly sent to the station control layer through optical fiber. At the same time, the local backup of the operating parameters is used as the basis for tracing and uploaded to the substation communication network through the merging unit and the intelligent terminal; The consistency detection of the same type of operation data includes: Dataset division: The running data is divided into data sets P. Data set P has n different types of running data M = {M1, M2, ...M n },M n Contains N samples m i ={m i1 ,m i2 ,...m iN }; Consistency test: All running data in the data set are fitted by the least squares method through a scatter plot, and then the fitted prediction value is used to verify the offset value of the same type of running data. The offset sequence B after fitting i The calculation formula is: Among them, y i is the i-th fitted value of the same type of running data, y i ′ is the i-th predicted value of the same type of running data; Abnormal detection and reporting: Based on the stable operation requirements of the substation, the maximum deviation threshold F is set c , if |B i |>F c , the operating data is considered abnormal. After testing all the operating data in the data set, the operating data of the fault is integrated and evaluated, and the fault-related information is uploaded to the substation network; The consistency detection of non-similar operation data includes: Regression equation establishment: Select a certain type of running data in the data set as the dependent variable v i , other types of operation data are listed as independent variables x ki , a regression equation is established to qualitatively detect the degree of deviation of running data. The calculation formula is: Among them, β0 is the random error, β1,β2,…,β p is the regression coefficient; Consistency detection and evaluation: The predicted value of the dependent variable is solved by the regression equation, and the maximum deviation threshold F is set based on the stable operation requirements of the substation. z , if |B i |>F z , the operating data is considered abnormal. After detecting all the operating data in the data set, the operating data of the fault is integrated and evaluated, and the fault-related information is uploaded to the substation network.

2. The intelligent substation fault analysis and rapid verification method considering information reliability according to claim 1 is characterized in that: The communication network structure and data transmission in S2 include: S21, establishment of redundant communication network structure: the smart substation adopts a three-layer two-network redundant communication network structure to monitor network devices and information flows, and upload fault information to the station control layer in a timely manner; S22, protect the redundant structure of AB sets: By protecting the redundant structure of AB sets, the reliability of the communication link is enhanced. The process layer acquisition device pre-processes the operating parameters. After the electronic transformer data is safety verified, the SV sampling message is output to the process layer SV switch through two sets of independent merging units; S23, independent data collection and control: using two sets of independent intelligent terminals to independently collect and control primary equipment, the operating parameters enter the process layer network through the process layer switch, and the process layer network uses GOOSE network and SV network to operate independently to improve the stability of the communication link; S24, data transmission between the bay layer and the station control layer: the bay layer equipment adopts a dual configuration, which connects to the primary equipment switch quantity signals uploaded by the process layer network A and network B and the analog signals of the continuously changing physical quantities in the substation, and uploads them to the station control layer through the station control layer switch. The station control layer MMS network adopts a dual configuration, and the bay layer equipment provides two Ethernet ports to connect to the MMSA network and the MMSB network respectively; S25, data presentation and monitoring: The substation operation data is presented to the station control layer monitoring host through the secondary system, and the operation and maintenance personnel can realize real-time monitoring and fault handling.

3. The intelligent substation fault analysis and rapid verification method considering information reliability according to claim 2 is characterized in that: The fault information analysis and processing in S3 includes: S31, fast parsing of SCD file: Parse the SCD file to obtain the status and logical relationship between the primary equipment and the secondary system of the substation, including the SV and GOOSE message publishing and subscription relationship between electronic devices, and the interaction and logical connection information of the input and output virtual terminals of electronic devices; S32, generate network topology: generate a network topology with substation equipment as nodes according to the parsed SCD file, parse the communication link information, update the fault information status, and if the communication link is abnormal or interrupted, generate a new network topology and prompt an alarm signal; S33, faulty equipment integration: Analyze SV or GOOSE message information, and determine the faulty equipment with interrupted secondary system network communication through virtual terminal connections between substation equipment; S34, fault information analysis and reporting: Use the SCD file to analyze the fault-related equipment, calculate the location probability of the faulty equipment, upload the fault location prediction and alarm information to the monitoring host, and record the relay protection action and automatic fault handling information for reference by the operation and maintenance personnel.

4. The intelligent substation fault analysis and rapid verification method considering information reliability according to claim 3 is characterized in that: The faulty equipment integration in S33 includes: S331, initial data set: Use the SCD file to analyze all substation equipment related to the fault information to form an initial data set E of the equipment related to the fault information, expressed as: And={e1,e2,e3,...,e n }; S332, construct a communication relationship matrix: construct a communication relationship matrix M, define a communication relationship function f(e i ,e j ) is the device e of this fault event i With equipment j The communication association between them is calculated as follows: S333, constructing a correlation data set: The correlation data set reflects the physical connection and logical connection relationship between devices. Based on the substation secondary system network structure and fault information, the location probability of the faulty device is obtained. The calculation formula is: M n =[f(e n ,e1)f(e n ,e2)...f(e n ,have been n )]; S334, generating a data set after the failure: the data set after the failure is expressed as: P=[f1,f2,...f n ] T ; Among them, the fault information includes equipment e n If there is no correlation in the data, the corresponding f value is 1, and if there is no correlation in the data, it is 0.

5. The intelligent substation fault analysis and rapid verification method considering information reliability according to claim 4 is characterized in that: The calculation formula of the location probability of the faulty device is: S n =M n ×P; Among them, S n The larger the value of is, the more likely the fault is caused by device n.

6. The intelligent substation fault analysis and rapid verification method considering information reliability according to claim 5 is characterized in that: The fault response and operation and maintenance monitoring in S4 include: S41, monitoring operation: Operation and maintenance personnel use the substation SCADA system operation terminal composed of monitoring host and telecontrol to realize the monitoring of the whole substation operation status; S42, fault detection and initial response: When the results of the multi-dimensional data safety detection and evaluation system at the process layer are abnormal or fault information appears at the station control layer, the operation and maintenance personnel analyze the fault and deal with it in a timely manner; S43, process layer data exception processing: When the process layer operating parameters are abnormal, the fault operating parameters are presented to the monitoring host through the optical fiber directly connected to the station control layer to assist the operation and maintenance personnel in determining the cause of the fault; S44, comprehensive fault analysis: when fault information appears at both the process layer and the station control layer, and the abnormal data matches the fault information, it is determined that the primary equipment has a fault; S45, pre-detection data abnormality processing: when the process layer pre-detection operating parameters are abnormal, and the station control layer does not have fault information, it is judged that the primary equipment of the substation is faulty and is attacked by the external network to cover up the primary equipment fault; S46, communication link fault processing: when the process layer data is normal, but the station control layer has fault information, it is determined that the substation secondary system communication link has a fault; S47, Fault repair and recovery: After repairing the secondary system fault, adjust the primary equipment switch quantity to normal state until the primary equipment and secondary system of the substation are stable and complete the manual maintenance.

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