Substation communication network reliability evaluation method, device, equipment, medium and product

Abstract

The invention discloses a substation communication network reliability evaluation method, device and equipment, a medium and a product, and relates to the technical field of network security. The method comprises the following steps: determining at least one intermediate fault event according to system partition information and a cross-region boundary device of a substation communication network system; determining a sub-fault tree corresponding to the intermediate fault event based on a recursive segmentation rule; the sub-fault tree comprises at least one line fault layer; each line fault layer comprises at least one fault node; the fault node corresponds to an equipment fault and / or a link fault; based on the communication path table, determining the bottom availability of at least one bottom fault event corresponding to the middle fault event; based on the sub-fault tree and the bottom availability, determining the middle availability of the middle fault event; and determining the total availability of the substation communication network system based on the at least one intermediate availability, and determining a target evaluation result based on the total availability. According to the embodiment of the invention, the evaluation accuracy can be improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of network security, and in particular to a substation communication network reliability evaluation method, device, equipment, medium and product. BACKGROUND

[0002] With the development of digitalization, informatization and intelligentization of the power system, as an important support for power grid dispatching and operation, the substation communication network is facing more stringent real-time, security and reliability requirements. Due to the simple architecture and limited device configuration of the traditional substation communication network, it is difficult to meet the demand of modern smart grid for data interaction in multiple business scenarios. With the accelerated construction of new power systems, self-controllable substations, as an important basic unit to realize the localization of key equipment in the power grid, the self-determination of hardware and software platforms, and the security of network systems, are being widely promoted in power engineering. The new generation of self-controllable substations significantly improves the anti-failure capability and security isolation capability of the system by adopting security partitioning, hierarchical isolation, dual-network redundancy, business main-auxiliary separation and core function trusted control and other technical means. Its network structure is more complex, the device logic coupling is enhanced, and the cross-zone fault conduction chain is longer. Therefore, it is necessary to deeply understand the network structure of the new generation of self-controllable substations, the coupling relationship between the security partitions, the data transmission and communication topology mode, and to carry out reliability evaluation and analysis according to the network communication characteristics.

[0003] Compared with traditional smart substations, the new generation of self-controllable substations introduce more complex security partitioning, main-auxiliary integrated communication, dual-network redundancy, and boundary isolation devices in the system architecture. Not only does it achieve localization substitution in hardware device selection, but it also presents strong logic coupling, frequent cross-zone transmission and strict partition security control in network logic and business interaction path. These characteristics make the communication network exhibit a significantly different fault propagation mode and reliability performance from traditional smart substations when facing node failure, redundancy switching, isolation blocking and other scenarios.

[0004] In view of the network communication structure characteristics of the new generation of self-controllable substations, it is necessary to establish a reliability evaluation method that fits the characteristics of multi-partition nesting, logic coupling and redundancy mechanism, in order to realize quantitative analysis and key bottleneck identification of the overall reliability of the communication system. SUMMARY

[0005] The present application provides a substation communication network reliability evaluation method, device, equipment, medium and product to solve the problem of low evaluation efficiency of the overall reliability of the communication system.

[0006] According to an aspect of the present application, a substation communication network reliability evaluation method is provided, comprising:

[0007] determine at least one intermediate fault event according to system partition information and cross-zone border devices of a substation communication network system;

[0008] determine a sub-fault tree corresponding to the intermediate fault event based on a recursive partition rule; the sub-fault tree comprises at least one line fault layer; each line fault layer comprises at least one fault node; the fault node corresponds to a device fault and / or a link fault;

[0009] determine a bottom availability of at least one bottom fault event corresponding to the intermediate fault event based on a communication path table;

[0010] determine an intermediate availability of the intermediate fault event based on the sub-fault tree and the bottom availability;

[0011] determine a total availability of the substation communication network system based on the at least one intermediate availability, and determine a target evaluation result based on the total availability.

[0012] According to another aspect of the present application, a substation communication network reliability evaluation device is provided, comprising:

[0013] an intermediate fault event determination module configured to determine at least one intermediate fault event according to system partition information and cross-zone border devices of a substation communication network system;

[0014] a sub-fault tree determination module configured to determine a sub-fault tree corresponding to the intermediate fault event based on a recursive partition rule; the sub-fault tree comprises at least one line fault layer; each line fault layer comprises at least one fault node; the fault node corresponds to a device fault and / or a link fault;

[0015] a bottom availability determination module configured to determine a bottom availability of at least one bottom fault event corresponding to the intermediate fault event based on a communication path table;

[0016] an intermediate availability determination module configured to determine an intermediate availability of the intermediate fault event based on the sub-fault tree and the bottom availability;

[0017] an evaluation result determination module configured to determine a total availability of the substation communication network system based on the at least one intermediate availability, and determine a target evaluation result based on the total availability.

[0018] According to another aspect of the present application, an electronic device is provided, comprising:

[0019] at least one processor; and a memory communicatively connected with the at least one processor; wherein the memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor to enable the at least one processor to perform the substation communication network reliability evaluation method according to any one of the embodiments of the present application.

[0020] According to another aspect of the present application, a computer readable storage medium is provided, which stores computer instructions for enabling a processor to implement the substation communication network reliability evaluation method according to any one of the embodiments of the present application when executed by the processor.

[0021] According to another aspect of the present application, a computer program product is provided, which comprises computer program / instructions for implementing the substation communication network reliability evaluation method according to any one of the embodiments of the present application when executed by a processor.

[0022] The embodiments of the present application determine at least one intermediate fault event according to system partition information and cross-border devices of a substation communication network system; determine a sub-fault tree corresponding to the intermediate fault event based on recursive partition rules; the sub-fault tree comprises at least one line fault layer; each line fault layer comprises at least one fault node; the fault node corresponds to device fault and / or link fault; determine the bottom availability of at least one bottom fault event corresponding to the intermediate fault event based on a communication path table; determine the intermediate availability of the intermediate fault event based on the sub-fault tree and the bottom availability; determine the total availability of the substation communication network system based on at least one intermediate availability, and determine a target evaluation result based on the total availability. The embodiments of the present application realize the precision and efficiency of substation communication network system availability evaluation through system partition, fault tree hierarchical, path table dependence and availability recursive calculation, and have significant improvement in accuracy and maintainability compared with traditional methods.

[0023] It should be understood that the content described in this part is not intended to identify key or important features of the embodiments of the present application, nor to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0025] Figure 1is a flow chart of a substation communication network reliability evaluation method provided by an embodiment of the present application;

[0026] Figure 2 is a network configuration schematic diagram provided by an embodiment of the present application;

[0027] Figure 3 is a sub-fault tree schematic diagram provided by an embodiment of the present application;

[0028] Figure 4 is a substation communication network structure schematic diagram provided by an embodiment of the present application;

[0029] Figure 5 is a flow chart of a substation communication network reliability evaluation method provided by an embodiment of the present application;

[0030] Figure 6 is a structure schematic diagram of a substation communication network reliability evaluation device provided by an embodiment of the present application;

[0031] Figure 7 is a structure schematic diagram of an electronic device for implementing a substation communication network reliability evaluation method provided by an embodiment of the present application. DETAILED DESCRIPTION

[0032] In order to enable persons skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by persons skilled in the art without creative work should fall within the scope of protection of the present application.

[0033] It should be noted that the terms "first", "second", and the like in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to only those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0034] In addition, it also needs to be explained that, in the technical solutions of the present application, the collected information is information and data authorized by the user or fully authorized by all parties, and the collection, storage, use, processing, transmission, provision, disclosure and application of related data comply with relevant laws, regulations and standards of relevant countries and regions, necessary security measures are taken, public order and good customs are not violated, and corresponding operation entrances are provided for users to choose authorization or refusal.

[0035] Figure 1 is a flowchart of a substation communication network reliability evaluation method provided by an embodiment of the present application. The embodiment can be applicable to the case of evaluating the reliability of a substation communication network. The method can be executed by a substation communication network reliability evaluation device. The device can be realized in the form of hardware and / or software. The device can be configured in an electronic device with corresponding data processing capability, such as a server. As shown in the figure, the method comprises the following steps. Figure 1

[0036] S110, determining at least one intermediate fault event according to system partition information of the substation communication network system and a cross-zone boundary device.

[0037] The system partition information refers to the division and function of different regions in the substation communication network system. The cross-zone boundary device refers to a device connecting different regions. The cross-zone boundary device is used to control the communication between different regions to ensure safety and reliability of data transmission.

[0038] Specifically, taking the “substation communication network overall failure” as the top event, and according to the system partition information of the substation communication network system and the cross-zone boundary device, the direct cause of the top event is summarized as at least one intermediate fault event.

[0039] S120, determining a sub-fault tree corresponding to the intermediate fault event based on a recursive partition rule; the sub-fault tree comprises at least one line fault layer; each line fault layer comprises at least one fault node; the fault node corresponds to a device fault and / or a link fault.

[0040] The recursive partition rule is used to recursively decompose the intermediate fault event into sub-events according to its logical relationship until the bottom fault event is reached. The sub-fault tree is a sub-structure after the decomposition of the fault tree. Each sub-fault tree corresponds to a fault path of an intermediate fault event. The sub-fault tree connects fault events through logical gates (such as AND gate, OR gate, etc.) to form a hierarchical structure. The line fault layer is a hierarchical structure in the sub-fault tree according to the fault category. Each line fault layer comprises at least one fault node. The fault node is a basic unit in the sub-fault tree. The fault node corresponds to a device fault and / or a link fault.

[0041] ​For example, if a smart substation 220 kV line interval is taken as a typical modeling object, a safety I zone fault is taken as a typical intermediate fault event, and the interval communication system adopts a dual configuration, respectively operating in I network and II network through A set and B set communication links to form a logically independent and physically isolated dual-path structure. According to the device topology, network switching structure and functional redundancy configuration of the communication system, a network configuration diagram of the interval can be established, as shown in FIG. 8. Figure 2 As shown in the structure, the A / B set acquisition and execution units respectively undertake data acquisition and action control functions, and the collected data is uploaded to the line protection device (A / B set) and the single set configured multifunctional measurement and control unit. The communication link is laid out through the station control layer switch, interval layer isolation switch and central switching device of the I network and II network to realize reliable transmission and aggregation processing of information. Due to the difference in device configuration and network layering strategy, the transmission paths of different communication services under the I / II network are significantly different, which is specifically manifested in that the combination of switching nodes passed between the source-destination node pair is different, thereby leading to the asymmetry of the dependence and failure influence path of the network link. Based on the above communication path analysis, a schematic diagram of the sub-fault tree of the 220 kV line interval is constructed based on the typical communication structure of the line interval A / B set, as shown in FIG. 9. The fault tree model expands its constituent paths from top to bottom based on the “220 kV line interval fault”, which is specifically divided into “I network A set device fault”, “I network B set device fault”, “II network A set device fault” and “II network B set device fault”. Figure 3

[0042] S130, determining the bottom availability of at least one bottom fault event corresponding to the intermediate fault event based on the communication path table.

[0043] The communication path table is a list or mapping table describing all the logical connection relationships of hardware, software and links relied on by the system to complete a specific communication function.

[0044] Specifically, each bottom fault event in the fault tree can find a corresponding entity (for example, a certain device) in the communication path table, so as to determine the bottom availability of at least one bottom fault event corresponding to the intermediate fault event based on the communication path table. The historical engineering statistical data includes the availability of the device, and the availability of the device is taken as the bottom availability of the corresponding bottom fault event, so as to determine the bottom availability of each bottom fault event.

[0045] S140, determining the intermediate availability of the intermediate fault event based on the sub-fault tree and the bottom availability.

[0046] The intermediate availability is the availability of the intermediate fault event.

[0047] ​Specifically, based on the given sub-fault tree model and the unavailability data of each bottom fault event, the intermediate availability of the intermediate fault event is calculated by applying the calculation formula of the logic gate (e.g., AND gate, OR gate, etc.) to each layer from the bottom fault event, and finally the intermediate availability of the intermediate fault event is calculated. The intermediate availability can be used to quantitatively evaluate the probability of the intermediate fault event working normally. By comparing the availabilities of different intermediate fault events, it can be quickly identified which subsystem or functional module in the system is the most unreliable and has the greatest impact on the overall reliability of the system. By decomposing the system into multiple subsystems, the reliability of each subsystem is calculated first, and then combined into the whole, greatly simplifying the analysis process and improving the analysis efficiency.

[0048] S150, determining the total availability of the substation communication network system based on the at least one intermediate availability, and determining a target evaluation result based on the total availability.

[0049] The total availability is the availability of the substation communication network system. The target evaluation result is the result obtained by evaluating the reliability of the substation communication network system.

[0050] Specifically, the substation communication network system is composed of at least one key functional subsystem (the availability of which is the "intermediate availability") according to a specific logical relationship. Based on the intermediate availability (such as the availability of the communication path) calculated in step S140, the total availability of the entire substation communication network system is determined, and the target evaluation result with practical engineering significance is obtained. When the total availability is determined, the total availability can be compared with the standard index to determine the target evaluation result, which can include passing or failing, for example, if the total availability is 0.9921 and the industry standard requires that the availability of the substation communication system should not be less than 0.9995, i.e. the standard index is 0.9995, then the target evaluation result is not up to standard. Thus, the local evaluation is pushed to the overall evaluation, and the guiding conclusion is obtained from the data.

[0051] Optionally, the method further comprises: when the target evaluation result is not up to standard, screening at least one bottom fault event based on at least one bottom availability, and taking the bottom fault event with the lowest bottom availability as the target fault event. Thus, it is convenient for technicians to carry out targeted maintenance based on the target fault event.

[0052] Optionally, the cross-zone boundary device includes a firewall and / or a positive and negative isolation device; the substation communication network includes a safety I zone, a safety II zone and a safety IV zone; a firewall is arranged between the safety I zone and the safety II zone, and a positive and negative isolation device is arranged between the safety II zone and the safety IV zone.

[0053] Among them, the safety I area is responsible for the monitoring, control and protection of the main equipment, adopts a three-layer network architecture, and contains the station control layer, the interval layer and the process layer. The safety II area is used for auxiliary equipment monitoring and management, including metering, dynamic ring monitoring and other functions. The safety IV area implements intelligent patrol functions, including video monitoring and inspection robots. Each partition adopts redundant configuration and layered isolation measures, such as double network architecture, optical fiber point-to-point communication and double clock synchronization system. The substation communication network structure diagram is shown in Figure 4 MMS (Multimedia Messaging Service) is a multimedia short message service, and GOOSE / SV (Generic Object Oriented Substation Event / Sampled Value) is an object-oriented general substation event / sampled value.

[0054] The substation communication network structure diagram shows the secondary system architecture of a substation, including protection and control equipment, communication network, auxiliary system and safety isolation measures and other components. The whole system is laid out according to the typical "three-layer two-network" structure of the digital substation, namely the process layer, the interval layer and the station control layer, and the network is isolated in combination with the safety area division (safety I area, safety II area, safety IV area). In the figure, each device realizes the interaction of power signals, control instructions and communication data through optical fiber Ethernet and hard points (traditional cable connection).

[0055] The substation communication network structure schematic diagram includes at least one flow, wherein the measurement and protection control flow: the operating parameters of the primary equipment (bus, line, transformer, etc.) of the power system are first acquired by the sensor: the current and voltage are sent to the merging unit for digitization through the transformer. The merging unit sends the accurate and synchronized sampling data to the network for real-time access by the relay protection device and the measurement and control device. At the same time, the state of the circuit breaker and the disconnector is collected by the intelligent terminal or directly transmitted to the measurement and control / protection device through the contact. Each protection device continuously calculates and monitors, and when a fault or abnormality is identified, immediately trips the output through the hard contact to trip the corresponding circuit breaker to remove the fault; and can notify the relevant equipment through GOOSE to take action or lock other sections. The measurement and control device executes the sequence control or remote control instruction to realize the normal opening and closing operation of the circuit breaker and the switch, and feeds back the operation result through the hard contact and the network. The whole process layer and the interval layer form a closed loop of protection and control circuit to ensure the safe and rapid control of the power flow of the primary equipment: once a short circuit occurs at a certain place, the protection device quickly disconnects the current at that place to change the power flow to avoid the expansion of the accident; when scheduling operation is required, the measurement and control unit receives the command to close or open the circuit to adjust the power network topology. The monitoring and dispatching flow: the state and measurement data of all interval layer devices (protection / control, etc.) are collected to the monitoring host through the station control layer network. The monitoring host serves as the human-machine interface, continuously refreshes the primary system wiring diagram and equipment working condition (voltage, current, switch state, etc.), provides an alarm list (such as protection action, equipment abnormality) for the operator to check. When the dispatcher or the on-site personnel issues a control instruction (such as remote closing), the instruction is sent to the corresponding measurement and control device through the communication gateway machine or the monitoring host for execution to complete the remote control of the primary equipment. The monitoring host also records historical data and events for post-analysis. Through the communication gateway machine, the substation is included in the dispatching automation system: the dispatching center receives the switch state and remote measurement value in the station in real time, monitors the power flow, and can remotely control the circuit breaker to be put into operation or removed, thereby realizing the macro adjustment and accident disposal of the power energy flow. The auxiliary system and alarm flow: the auxiliary systems such as fire protection, security protection, power environment, etc. independently run in the background, but the key alarms and states are sent to the monitoring host and the remote patrol system through the contact or interface. Once a fire or illegal intrusion occurs, the monitoring host interface will pop up an alarm to remind the operator, and the remote operation and maintenance center can also receive the alarm information for timely handling. At the same time, if the power environment system detects air conditioning failure, high temperature and humidity, etc., it will also report an alarm to ensure the reliable operation of the auxiliary facilities in the substation. These auxiliary signals do not directly affect the power flow, but through the centralized alarm of the monitoring system, the response speed of the power station operation and maintenance is improved, which indirectly ensures the safety of the power system. The data analysis and operation and maintenance flow: in the safety II area in the station, the host computer and the secondary online monitoring terminal are comprehensively applied to further analyze and process the massive data from the station control layer.The online monitoring terminal continuously self-checks the secondary circuit and device state. Once it finds phenomena such as poor contact of a contact, abnormal battery feeding, abnormal reset of a protection device, etc., it generates an alarm or a maintenance item for suggestion and sends it to the comprehensive application host for storage and reporting to the operation and maintenance platform. The comprehensive application host also collects data of professional devices such as power quality, synchronous phasor, fault location, etc., generates a report or uploads it to a professional analysis center. Every day, the patrol host safely extracts these data through a service gateway and automatically generates a remote patrol report including device running state, alarm summary, trend analysis, etc. for review by the operation and maintenance personnel. If there is an abnormality, the operation and maintenance personnel can perform remote diagnosis on the relevant devices in the station through an authorized channel of the service gateway or decide to send personnel to the site for maintenance. The whole process realizes the condition-based maintenance strategy of the unattended substation: relying on online monitoring and remote patrol, problems are found in advance, maintenance is performed as needed, and accidents are avoided. Safety protection measures: The network security area isolation strategy is strictly implemented in the system architecture. The control area (security I area) and the management area (security II area) in the station are isolated by a network security device (firewall), only allowing necessary data to flow in one direction to prevent unauthorized access from endangering the protection control system. Similarly, the management area in the station transmits data to the external operation and maintenance network or the Internet (security IV area) only through a one-way network barrier / isolation device, and any communication request from the outside cannot directly enter the control area. In this way, combined with the closed nature of the substation special communication network, the information security threat is resisted to ensure the reliable operation of the protection and control system. At the same time, at the physical level, hard contact connection ensures that even if the network is disturbed, the most critical trip action can still be reliably executed and will not fail due to communication failure. The logical isolation between the security areas is realized through the clear boundary device, while the controlled data interaction path is reserved. The security I area and the II area are connected through the firewall to realize data bidirectional filtering and access control; the security II area and the IV area are connected through the positive and negative isolation device to realize data unidirectional flow, ensuring the safe and controllable upload of security and patrol information; the public support systems such as time synchronization system and power supply system are laid across the areas, and their failure may affect the synchronous communication of multiple areas.

[0056] Optionally, the intermediate fault event includes a security I area network fault, a security II area network fault, a security IV area network fault, a firewall fault, a positive and negative isolation device fault, an integrated power supply system fault, or a time synchronization system fault.

[0057] Specifically, based on the substation safety partition, open hierarchical distributed structure characteristics, taking the "substation communication network failure" as the top event, and according to the characteristics of the safety partition architecture, the direct causes leading to the top event are divided into the following three categories: the first category: partition network failure event, refers to the network failure within the partition that undertakes the communication function, all redundant communication links or key switching devices within the partition fail, which is the security I area network failure, security II area network failure, security IV area network failure; the second category: inter-zone isolation device failure event, refers to the communication blockage or network security incident between partitions, thereby affecting the communication reliability of the whole station, which is the firewall failure and the positive and negative isolation device failure; the third category: support system failure event, the reliable operation of the communication network depends on stable power supply and unified time synchronization, if it fails to cause the communication equipment to lose power or the devices lose unified time base, it will greatly affect the network availability, mainly the integrated power system failure and time synchronization system failure. The power supply system, clock synchronization system and other cross-zone support systems are modeled as intermediate fault events, which enhances the completeness of the fault propagation path. As can be seen, all the direct causes of the top event can be summarized into seven intermediate fault events, namely security I area network failure, security II area network failure, security IV area network failure, firewall failure, positive and negative isolation device failure, integrated power system failure or time synchronization system failure. These intermediate fault events present an "or" logical relationship due to the partition isolation strategy, that is, as long as any one of the events occurs, it will trigger the occurrence of the whole station communication network failure top event.

[0058] The embodiment of the application divides a complex network into logically isolated fault events through system partitioning and definition of cross-zone boundary devices, avoids the problem of ambiguous definition of fault events in traditional overall analysis, and improves fault positioning accuracy to the device level / link level. The hierarchical construction of the sub-fault tree is realized through recursive segmentation rules, so that the sub-fault tree can be dynamically adjusted according to network topology changes, for example, when an interval device is added, only the fault nodes at the corresponding level need to be supplemented, without the need to reconstruct the entire tree, significantly improving the model maintenance efficiency. The bottom availability of the bottom fault event is determined based on the communication path table, ensuring the physical reality of the quantitative basis, and the availability and the actual network topology are strongly bound through the path table, so that the bottom event availability has traceability and verifiability. Through recursive calculation of the sub-fault tree and the bottom availability, the availability aggregation from the bottom fault event to the intermediate fault event is realized. The total availability as a system-level indicator can intuitively reflect the overall reliability level of the substation communication network system, and when the total availability is lower than the standard indicator, it can be traced back to the specific fault node, thereby guiding the targeted maintenance of the operation and maintenance personnel. This evaluation result of "global indicator + local positioning" meets the macro-control demand of technical personnel on system reliability, and provides a specific fault troubleshooting direction for the technical personnel, realizing the closed loop from evaluation to decision. Through system partitioning, hierarchical fault tree, path table dependence and availability recursive calculation, the embodiment of the application realizes the precision and efficiency of the reliability evaluation of the substation communication network system, and significantly improves the accuracy and maintainability compared with the traditional method.

[0059] Figure 5 is a flowchart of a substation communication network reliability evaluation method provided by the embodiment of the application. Based on the above-mentioned embodiment, the bottom availability of at least one bottom fault event corresponding to the intermediate fault event is optimized based on the communication path table, and an optional implementation scheme is provided. As shown in Figure 5 , the method comprises:

[0060] S210, determining at least one intermediate fault event according to system partitioning information and cross-zone boundary devices of the substation communication network system.

[0061] S220, determining a sub-fault tree corresponding to the intermediate fault event based on a recursive segmentation rule; the sub-fault tree comprises at least one line fault layer; each line fault layer comprises at least one fault node; and the fault node corresponds to device fault and / or link fault.

[0062] S230, for each bottom fault event corresponding to the intermediate fault event, obtaining at least one device corresponding to the bottom fault event from the communication path table.

[0063] Specifically, the transmission path information corresponding to each bottom fault event is obtained from the communication path table, and at least one device corresponding to the bottom fault event is determined based on the transmission path information. For example, the communication path table is shown in Table 1, and the details are described in combination with Figure 2 The network configuration diagram is shown, and the data uploading working condition of the I network A set of devices is taken as an example. The data needs to be collected from the A set of collection and execution units, the communication flow (MA1) is analyzed to the A set of protection units, and at the same time, the communication flow (MA2) is uploaded to the measurement and control device input signal. The data of the protection device is uploaded to the center switch through the communication flow (MA3 and MA4, M7) via each layer switch, and the measurement and control unit is also uploaded to the center switch through the communication flow (M9 and M10). The communication network transmission of the 220kV line interval is completed, and in the data transmission, any unit or communication chain failure will cause the whole network transmission failure. The devices corresponding to the I network A set of device fault events include the collection and execution unit (A), the protection unit (A), the multifunctional measurement and control (MMC), the station control layer switch (C1), the station control layer switch (A1), the isolation switch (1), the center switch (1), the communication link (MA1), the communication link (MA2), the communication link (MA3), the communication link (MA4), the communication link (M7), the communication link (M9), and the communication link (M10).

[0064]

[0065] S240, determining the device availability from the device information of the device.

[0066] The device information includes device name, device identifier, unavailability, and availability, etc.

[0067] Specifically, the device availability can be obtained based on the device information table. The device information table includes device information of at least one device. For example, the device information table is shown in Table 2. The unavailability data and the availability data in the device information table are determined based on the reliability index given by the collection and execution unit, the engineering operation data, and the manufacturer's production manual.

[0068]

[0069] For the bottom fault event, if there is unavailability data and availability data in the device information table, the value is directly taken; if there is only the failure rate and the repair rate of the device, the unavailability of the device is calculated based on the failure rate and the repair rate of the device using the device unavailability calculation formula, and the difference obtained by subtracting the unavailability from 1 is taken as the availability of the device. The device unavailability calculation formula is

[0070]

[0071] wherein, is the failure rate of the i-th device, is the repair rate of the i-th device, is the unavailability of the i-th device. The failure rate of a device is the probability of the device failing in a unit of time. The repair rate of a device is the rate at which the device is repaired and returns to work after a failure, and the repair rate is the inverse of the repair time (MTTR, Mean Time To Repair). The repair time can be obtained from historical maintenance data, manufacturer repair guidelines, or engineering experience statistics of similar devices. If actual data is lacking, industry standard recommended values or experience parameters of similar devices can also be used.

[0072] S250, based on the device availability, determining the bottom availability of the bottom failure event.

[0073] Specifically, taking the I-net A set of device failure events as an example, the I-net A set of device failure expression is:

[0074] wherein, is the I-net A set of device failure events, is the I-net A set of communication link failure events, is the I-net A set of device failure events, , that is:

[0075]

[0076]

[0077] wherein, is the expression of each communication flow failure, is the expression of each device failure.

[0078] The bottom availability of the I-net A set of device failure events is determined based on the availability of the seven communication links (MA1-MA4, M7, M9, and M10), the availability of the acquisition execution unit (A), the availability of the protection unit (A), the availability of the multifunctional measurement and control (MMC), the availability of the station control layer switch (C1), the availability of the station control layer switch (A1), the availability of the isolation switch (1), and the availability of the center switch (1), that is,

[0079] A1 220L = 0.99952 * 0.9998 7 * 0.9988 * 0.9988 * 0.999 * 0.999 * 0.999 * 0.998 = 0.9907577743

[0080] wherein, A1 220L is the bottom availability of the I-net A set of device failure events.

[0081] S260, determining the intermediate availability of the intermediate fault event based on the sub-fault tree and the bottom availability.

[0082] S270, determining the total availability of the substation communication network system based on the at least one intermediate availability, and determining the target evaluation result based on the total availability.

[0083] Optionally, the recursive segmentation rule is to recursively segment in the order of hierarchy, topology, and redundancy; the hierarchy includes station control layer, bay layer, and process layer; the topology includes switching, link, and node; the redundancy includes first communication link, second communication link, first network, and second network.

[0084] The hierarchy refers to classifying things according to different levels. The topology refers to the network topology structure, which refers to the way of connection between nodes in the network. The redundancy refers to the redundant components in the system. The station control layer is used for centralized monitoring of the whole station, data aggregation, dispatching instruction issuance, and human-computer interaction, for example, real-time display of device parameters of the whole station through a high-performance server, remote control of circuit breaker action, and communication with the power grid dispatching center. The bay layer is used to undertake device-level protection, measurement and control tasks, and the bay layer corresponds to specific electrical bays (such as transformer bays, busbar bays), for example, line protection devices monitor current in real time, trigger tripping when a fault occurs, and upload event information to the station control layer. The process layer is used to directly connect primary devices (such as circuit breakers, transformers), complete electrical quantity detection (such as current / voltage digitization), state monitoring, and control command execution, for example, a merging unit converts analog signals into digital signals, and an intelligent terminal executes opening and closing operations. The substation communication network system includes three levels of station control layer, bay layer, and process layer. Switching refers to the forwarding and path selection of data frames through switches and other devices, for example, in a star topology, a central switch controls the communication of all nodes; in a mesh topology, multi-path redundancy improves reliability. The node refers to the data processing / communication device in the substation communication network, for example, a switch as a transit node supports data forwarding, and a host as an access node initiates / receives data. The link refers to the connection between nodes. The substation communication network system adopts double-network and double-link redundancy, which includes link redundancy and network redundancy. The first communication link and the second communication link are channels in the primary / backup dual-link architecture, for example, the first communication link can be the primary link, which is used to undertake daily data transmission, and the second link can be the backup link, which is used to take over traffic when the primary link fails. The first network and the second network are independent network planes in the dual-network redundancy architecture, for example, the first network can be the primary network, which is used to carry main services, and the second network can be the backup network, which is used to provide redundancy support when the primary network fails.

[0085] Specifically, the system is divided into a station control layer, a bay layer and a process layer according to a hierarchical division; each layer is divided into a switch, a link and a node according to a topological division; a redundancy strategy is applied to each topological part, such as a first communication link and a second communication link, a first network and a second network redundancy. For example, in the station control layer, a failure of a switch device can be involved, which is further divided into a link failure or a device failure, and then a redundancy strategy such as a backup link or a backup network is applied.

[0086] Optionally, based on the sub-fault tree and the bottom availability, the intermediate availability of the intermediate fault event is determined, including: determining the logical relationship between different bottom fault events corresponding to the intermediate fault event based on the hierarchical relationship of the sub-fault tree; and determining the intermediate availability of the intermediate fault event based on the logical relationship and the bottom availability.

[0087] The hierarchical relationship is the position and level of the fault event in the sub-fault tree. The logical relationship is the logical connection between the fault events, such as an AND gate, an OR gate, etc. For example, an AND gate indicates that all input events must occur to cause an output event, or an OR gate indicates that any input event can occur. The logical relationship determines how the bottom events are combined to cause the occurrence of the intermediate fault event.

[0088] Specifically, the availability of the substation communication network system is quantitatively evaluated, which can be: based on the hierarchical relationship of the sub-fault tree, the logical relationship between different bottom fault events corresponding to the intermediate fault event is determined, and the logical relationship includes an AND gate, an OR gate, etc. Taking the network fault event of the safety I area as an example, according to Figure 3 , the safety I area network fault includes I network fault and II network fault of the safety I area, the I network fault includes I network A set device fault and I network B set device fault, and the II network fault includes II network A set device fault and II network B set device fault, which can be combined respectively to obtain the availability of the safety I area, and other partitions are executed by analogy to obtain the intermediate availability of all intermediate fault events. It is convenient for subsequent evaluation of the total availability of the system based on the availability of at least one intermediate fault event to form the final evaluation result, and to carry out weak link identification and importance analysis accordingly. The availability calculation formula of the I network A set device is:

[0089]

[0090] wherein, is a set of all devices in the I network A set device, is the availability of the I network A set device, is the unavailability of the i-th device, and i is a positive integer. The availability calculation formula of the II network A set device, the availability calculation formula of the I network B set device, and the availability calculation formula of the II network B set device are similar.

[0091] The availability calculation formula of the I-network is

[0092]

[0093] wherein, is the availability of the I-network A set of equipment, is the availability of the I-network B set of equipment.

[0094] The availability calculation formula of the safety I-zone is

[0095]

[0096] wherein, is the availability of the I-network, is the availability of the II-network. The intermediate availability calculation process of the remaining intermediate fault events is similar.

[0097] The traditional fault tree is mainly based on the single-zone modeling of equipment failure, and the safety partition characteristics of the autonomous controllable substation are introduced in the embodiment of the application, the data interaction and logical coupling mechanism across the zones are included in the tree modeling, which is more in line with the actual operation scene. The embodiment of the application considers the double-network redundancy, double-set configuration of equipment and other multiple redundancy strategies, and reflects the contribution of reliability and common-mode fault risk through logical modeling. The embodiment of the application not only describes the logical relationship, but also proposes a formula calculation method of equipment unavailability, intermediate availability and the like. Thus, the reliability evaluation is realized by using the improved fault tree model, the reliability contribution of the substation communication network structure and the redundancy configuration is intuitively reflected through the fault tree analysis, and a theoretical basis is provided for the identification of key equipment and weak links.

[0098] Figure 6 Fig. 1 is a structural schematic diagram of a substation communication network reliability evaluation device provided by the embodiment of the application. The embodiment can be applicable to the case of evaluating the reliability of the substation communication network, and the device can be realized in the form of hardware and / or software. The device can be configured in an electronic device with corresponding data processing capability, such as a server. As shown in Fig. 1, the device comprises: Figure 6

[0099] The intermediate fault event determination module 310 is configured to determine at least one intermediate fault event according to the system partition information and the cross-zone boundary device of the substation communication network system.

[0100] The sub-fault tree determination module 320 is configured to determine a sub-fault tree corresponding to the intermediate fault event based on a recursive partition rule. The sub-fault tree comprises at least one line fault layer, and each line fault layer comprises at least one fault node. The fault node corresponds to equipment failure and / or link failure.

[0101] ​The bottom availability determination module 330 is configured to determine, based on the communication path table, a bottom availability of at least one bottom fault event corresponding to the intermediate fault event;

[0102] The intermediate availability determination module 340 is configured to determine, based on the sub-fault tree and the bottom availability, an intermediate availability of the intermediate fault event.

[0103] The evaluation result determination module 350 is configured to determine, based on the at least one intermediate availability, a total availability of the substation communication network system, and determine the target evaluation result based on the total availability.

[0104] The embodiment of the present application divides a complex network into logically isolated fault events through system partitioning and definition of cross-zone boundary devices, which avoids the problem of ambiguous fault event definition in traditional overall analysis, and improves fault positioning accuracy to the device level / link level. The hierarchical construction of the sub-fault tree is realized through recursive segmentation rules, so that the sub-fault tree can be dynamically adjusted according to network topology changes. For example, when a new interval device is added, only the fault node needs to be supplemented at the corresponding level, without the need to reconstruct the entire tree, which significantly improves the model maintenance efficiency. The bottom availability of the bottom fault event is determined based on the communication path table, which ensures the physical reality of the quantitative basis. The availability and the actual network topology are strongly bound through the path table, so that the bottom event availability has traceability and verifiability. Through recursive calculation of the sub-fault tree and the bottom availability, the availability aggregation from the bottom fault event to the intermediate fault event is realized. The total availability as a system-level index can intuitively reflect the overall reliability level of the substation communication network system. When the total availability is lower than the standard index, it can be traced back to the specific fault node, thereby guiding the targeted maintenance of the operation and maintenance personnel. This evaluation result of "global index + local positioning" meets the macro-control demand of technical personnel on system reliability, and provides a specific fault troubleshooting direction for technical personnel, realizing the closed loop from evaluation to decision. The embodiment of the present application realizes the precision and efficiency of substation communication network system availability evaluation through system partitioning, hierarchical fault tree, path table dependence and recursive availability calculation, which significantly improves the accuracy and maintainability compared with traditional methods.

[0105] Optionally, the cross-zone boundary device includes a firewall and / or a positive and negative isolation device; the substation communication network includes a safety I zone, a safety II zone and a safety IV zone; the firewall is arranged between the safety I zone and the safety II zone, and the positive and negative isolation device is arranged between the safety II zone and the safety IV zone.

[0106] Optionally, the intermediate fault event includes a safety I zone network fault, a safety II zone network fault, a safety IV zone network fault, a firewall fault, a positive and negative isolation device fault, an integrated power supply system fault or a time synchronization system fault.

[0107] Optionally, the recursive partitioning rule is to recursively partition in the order of hierarchy, topology and redundancy; the hierarchy includes station control layer, bay layer and process layer; the topology includes switch, link and node; and the redundancy includes first communication link, second communication link, first network and second network.

[0108] Optionally, the bottom availability determining module 330 comprises:

[0109] The device determining unit is configured to, for each bottom fault event corresponding to the intermediate fault event, acquire at least one device corresponding to the bottom fault event from the communication path table;

[0110] The device availability determining unit is configured to determine the device availability from the device information of the device;

[0111] The bottom availability determining unit is configured to determine the bottom availability of the bottom fault event based on the device availability.

[0112] Optionally, the intermediate availability determining module 340 comprises:

[0113] The logical relationship determining unit is configured to determine the logical relationship between different bottom fault events corresponding to the intermediate fault event based on the hierarchical relationship of the sub-fault tree;

[0114] The intermediate availability determining unit is configured to determine the intermediate availability of the intermediate fault event based on the logical relationship and the bottom availability.

[0115] The substation communication network reliability evaluation device provided by the embodiment of the present application can perform the substation communication network reliability evaluation method provided by any embodiment of the present application, and has the corresponding function modules and beneficial effects of performing the method.

[0116] According to the embodiments of the present application, the present application further provides an electronic device, a readable storage medium and a computer program product.

[0117] Figure 7 A structural schematic diagram of an electronic device 10 that can be used to implement embodiments of the present application is shown. The electronic device is intended to represent various forms of digital computers, such as laptops, desktops, tablets, personal digital assistants, servers, blade servers, mainframes, and other appropriate computers. The electronic device can also represent various forms of mobile devices, such as personal digital processors, cellular telephones, smart phones, wearable devices (e.g., headsets, glasses, watches, etc.), and other similar computing devices. The components shown here, their connections and relationships, and their functions, are meant to be examples only, and are not intended to limit the implementations of the present application described and / or claimed in this document.

[0118] As Figure 7As shown, the electronic device 10 includes at least one processor 11, and a memory, such as a read-only memory (ROM) 12, a random access memory (RBM) 13, etc., connected to the at least one processor 11 in communication. The memory stores computer programs executable by the at least one processor 11, and the processor 11 can perform various appropriate actions and processes according to the computer programs stored in the read-only memory (ROM) 12 or loaded from the storage unit 18 into the random access memory (RBM) 13. In the RBM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12, and the RBM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0119] Various components in the electronic device 10 are connected to the I / O interface 15, including an input unit 16, such as a keyboard, a mouse, etc., an output unit 17, such as various types of displays, a speaker, etc., a storage unit 18, such as a magnetic disk, an optical disk, etc., and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices through a computer network, such as the Internet, and / or various telecommunication networks.

[0120] The processor 11 can be various general and / or special purpose processing components having processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 performs various methods and processes described above, such as the substation communication network reliability evaluation method.

[0121] In some embodiments, the substation communication network reliability evaluation method can be implemented as a computer program tangibly embodied in a computer readable storage medium, such as the storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed onto the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RBM 13 and executed by the processor 11, one or more steps of the substation communication network reliability evaluation method described above can be performed. Alternatively, in other embodiments, the processor 11 can be configured to perform the substation communication network reliability evaluation method by any other appropriate means, such as by means of firmware.

[0122] The various embodiments of the systems and techniques described above can be implemented in digital electronic circuitry, integrated circuitry, a field programmable gate array (FPGA), a system on a chip (SOC), a load programmable logic device (CPLD), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include implementation in one or more computer programs that are executable and / or interpretable on a programmable system including at least one programmable processor, which can be special or general purpose, coupled to receive data and instructions from, and to transmit data and instructions to, a storage system, at least one input device, and at least one output device.

[0123] Computer programs used to implement the processes of the application can be written in any combination of one or more programming languages. These computer programs can be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the computer program, when executed, can cause instructions defined in the flow charts and / or block diagrams to be implemented. The computer program can be executed entirely on a machine, partially on a machine, partially on a machine as a standalone software package and partially on a remote machine or entirely on a remote machine or server.

[0124] In the context of the present application, a computer-readable storage medium can be a tangible medium that can contain or store computer programs for use by or in connection with an instruction execution system, apparatus, or device. Computer-readable storage media can include, but are not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium can be a machine-readable signal medium. More specific examples of the machine-readable storage medium will include one or more lines of electrical connections, portable computer disks, hard disk drives, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or Flash memory), optical fibers, portable compact disc read-only memories (CD-ROMs), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0125] To provide for interaction with a user, the systems and techniques described here can be implemented on an electronic device having a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user and a keyboard and a pointing device (e.g., a mouse or a trackball) by which the user can provide input to the electronic device. Other kinds of devices can be used to provide for interaction with a user as well; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form, including acoustic, speech, or tactile input.

[0126] The systems and techniques described here can be implemented in a computing system that includes a back end component (e.g., as a data server), or that includes a middleware component (e.g., an application server), or that includes a front end component (e.g., a user computer having a graphical user interface or a Web browser through which a user can interact with an implementation of the systems and techniques described here), or any combination of such back end, middleware, or front end components. The components of the system can be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include a local area network ("LAN"), a wide area network ("WAN"), a blockchain network, and the Internet.

[0127] The computing system can include clients and servers. A client and server are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by virtue of computer programs running on the respective computers and having a client-server relationship to each other. A server can be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system, to solve the defects of large management difficulty and weak business scalability in traditional physical host and virtual private service.

[0128] It should be understood that the various forms of flow shown above can be re-ordered, added to, or deleted from without departing from the scope of the present disclosure. For example, the steps recited in the present disclosure can be executed in parallel, executed in sequence, or executed in a different order, as long as the desired results of the present disclosure are achieved, and the present disclosure is not limited herein.

[0129] The specific embodiments described above are not intended to be limiting, and persons skilled in the art will appreciate that various modifications, combinations, sub-combinations and alternatives can be made to the specific embodiments without departing from the spirit and principles of the disclosure. Accordingly, the disclosure is not limited to the specific embodiments described above, but only by the scope of the appended claims.

Claims

1. A method for assessing the reliability of a substation communication network, characterized in that, The method includes: Based on the system partitioning information of the substation communication network system and the cross-regional boundary devices, at least one intermediate fault event is identified; Based on recursive segmentation rules, a sub-fault tree corresponding to the intermediate fault event is determined; the sub-fault tree includes at least one line fault layer; each line fault layer includes at least one fault node; the fault node corresponds to equipment fault and / or link fault. Based on the communication path table, determine the minimum availability of at least one minimum failure event corresponding to the intermediate failure event; Based on the sub-fault tree and the bottom availability, determine the intermediate availability of the intermediate fault event; The total availability of the substation communication network system is determined based on at least one intermediate availability, and the target evaluation result is determined based on the total availability.

2. The method according to claim 1, characterized in that, The cross-zone boundary device includes a firewall and / or a positive and negative isolation device; the substation communication network includes Security Zone I, Security Zone II, and Security Zone IV; a firewall is installed between Security Zone I and Security Zone II, and a positive and negative isolation device is installed between Security Zone II and Security Zone IV.

3. The method according to claim 1, characterized in that, The intermediate failure events include network failures in Security Zone I, Security Zone II, and Security Zone IV, firewall failures, positive and negative isolation device failures, integrated power system failures, or time synchronization system failures.

4. The method according to claim 1, characterized in that, The recursive segmentation rule is to perform recursive segmentation in the order of hierarchy, topology, and redundancy; the hierarchy includes station control layer, interval layer, and process layer; the topology includes switching, links, and nodes; the redundancy includes a first communication link, a second communication link, a first network, and a second network.

5. The method according to claim 1, characterized in that, The step of determining the basic availability of at least one basic failure event corresponding to the intermediate failure event based on the communication path table includes: For each underlying fault event corresponding to the intermediate fault event, at least one device corresponding to the underlying fault event is obtained from the communication path table; Determine the availability of the equipment from its equipment information; Based on the device availability, the bottom availability of the bottom failure event is determined.

6. The method according to claim 1, characterized in that, Determining the intermediate availability of the intermediate failure event based on the sub-fault tree and the bottom availability includes: Based on the hierarchical relationship of the sub-fault tree, the logical relationship between different bottom fault events corresponding to the intermediate fault events is determined; Based on the logical relationship and the baseline availability, the intermediate availability of the intermediate failure event is determined.

7. A fault tree-based reliability assessment device for substation communication networks, characterized in that, The device includes: The intermediate fault event determination module is used to determine at least one intermediate fault event based on the system partitioning information of the substation communication network system and the cross-regional boundary devices. The sub-fault tree determination module is used to determine the sub-fault tree corresponding to the intermediate fault event based on recursive segmentation rules; the sub-fault tree includes at least one line fault layer; each line fault layer includes at least one fault node; the fault node corresponds to equipment fault and / or link fault. The low availability determination module is used to determine the low availability of at least one low failure event corresponding to the intermediate failure event based on the communication path table. An intermediate availability determination module is used to determine the intermediate availability of the intermediate failure event based on the sub-fault tree and the bottom availability. The evaluation result determination module is used to determine the total availability of the substation communication network system based on at least one intermediate availability, and to determine the target evaluation result based on the total availability.

8. An electronic device, characterized in that, The electronic device includes: At least one processor; and a memory communicatively connected to the at least one processor; The memory stores a computer program that can be executed by the at least one processor, which is then executed by the at least one processor to enable the at least one processor to perform the fault tree-based substation communication network reliability assessment method according to any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that cause a processor to execute the fault tree-based substation communication network reliability assessment method according to any one of claims 1-6.

10. A computer program product comprising a computer program that, when executed by a processor, implements the fault tree-based substation communication network reliability assessment method according to any one of claims 1-6.

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