Dcs event trace method and system based on control logic analysis

Abstract

This disclosure pertains to the field of nuclear power technology, specifically relating to a DCS event tracing method and system based on control logic analysis. The method reads and stores shutdown signals, safety-level channel signals, and non-safety-level logic signals from the DCS system in real time. Upon detecting an unexpected event at a nuclear power plant, it identifies the initial shutdown signal from the stored shutdown signals. Based on the fault tree, it determines the minimum cut set of the initial safety-level logic channel signals corresponding to the initial shutdown signal and identifies the corresponding non-safety logic signals. Using a fault knowledge base, it determines the key event sequence associated with the obtained non-safety logic signals, generates a report, and pushes it to relevant personnel. This enables rapid identification of the initial event signal after an unexpected event occurs, allowing for event cause tracing analysis and improving the efficiency and accuracy of event tracing.

Description

Technical Field

[0001] This invention belongs to the field of nuclear power technology, specifically relating to a DCS event tracing method and system based on control logic analysis. Background Technology

[0002] The DCS (Distributed Control System) is the "nerve center" of a nuclear power plant, monitoring and controlling the entire plant's operation. When a nuclear power plant unit experiences an abnormal operation, the DCS issues an alarm signal. By reverse-engineering the process by which the DCS generates this alarm signal, the cause of the abnormality can be identified, allowing for accurate action to eliminate it. Nuclear power unit process systems are complex and highly automated, resulting in a very large and complex control logic for the DCS system. It monitors a vast number of process parameters, many of which are coupled, making manual analysis of DCS system faults difficult and labor-intensive. Furthermore, manually tracing, predicting, and reproducing faults is challenging because it's difficult to present the analysis process and results clearly and concisely, hindering information transmission and increasing the difficulty of DCS system maintenance. Therefore, improving the efficiency and accuracy of DCS event tracing is a pressing issue. Summary of the Invention

[0003] To overcome the problems existing in related technologies, a DCS event tracing method and system based on control logic analysis is provided.

[0004] According to one aspect of the embodiments of this disclosure, a DCS event tracing method based on control logic parsing is provided, the method comprising:

[0005] Step 10: Read and store shutdown signals, safety-level channel signals and non-safety-level logic signals from the DCS system in real time;

[0006] Step 11: In the event of an unexpected event at the nuclear power plant, the first shutdown signal is determined from the stored shutdown signals. Based on the fault tree, the minimum cut set of the first safety-level logic channel signal corresponding to the first shutdown signal is determined, and the non-safety logic signal corresponding to the minimum cut set is determined. The first shutdown signal is the first shutdown signal triggered, and the first safety-level channel signal is the first safety-level channel signal or combination signal triggered. In the fault tree, the shutdown signal is the top event signal, the safety-level channel signal is the intermediate event signal, and the non-safety-level logic signal is the bottom event signal.

[0007] Step 12: Based on the fault knowledge base, determine the key event sequence associated with the non-safety logic signal obtained in the previous step. The fault knowledge base includes multiple key event sequences, the triggering location of the key events, and the real-time status of important equipment.

[0008] Step 13: Based on the key event sequence corresponding to the unexpected event, generate a source map and event report, and push them to the associated account.

[0009] In one possible implementation, the method further includes:

[0010] Step 20: Parse the safety-level DCS configuration file to obtain the minimum cut set that triggers each shutdown signal. Among them, a single signal corresponding to a logic OR gate is the minimum cut set, and a group of signals corresponding to a logic AND gate is the minimum cut set. Based on the minimum cut set that triggers each shutdown signal, construct a two-layer fault tree with the shutdown signal as the top event and the safety-level channel logic signal as the bottom event, and the combination of minimum cut sets of safety-level logic channel signals as the top event and non-safety-level logic signals and associated fault knowledge base as the bottom events.

[0011] In one possible implementation, the method further includes:

[0012] Step 30: Analyze the log format and rules of the DCS log file, classify and grade the log entries according to the equipment level and protection function level information, and combine the signal transmission relationship in the control logic to analyze and extract the key event sequence, locate the trigger position of the key event and the real-time status of important equipment, and build a fault knowledge base.

[0013] In one possible implementation, step 12 further includes:

[0014] Step 120: When analyzing and tracing the source of key events based on the sequence of key events, determine the correlation between output changes and input changes in the control algorithm according to the operation rules of the encapsulated control module of the DCS system, and determine the key event sequence associated with non-safety logic signals based on the correlation.

[0015] According to another aspect of the embodiments of this disclosure, a DCS event tracing system based on control logic parsing is provided, the system including a computation layer and an interaction layer;

[0016] The computation layer includes: an acquisition module, a first determination module, and a second determination module;

[0017] The acquisition module is used to read and store shutdown signals, safety-level channel signals and non-safety-level logic signals from the DCS system in real time.

[0018] The first determining module is used to determine the first shutdown signal from the stored shutdown signals when an unexpected event is detected at the nuclear power plant, determine the minimum cut set of the first safety level logic channel signal corresponding to the first shutdown signal according to the fault tree, and determine the non-safety logic signal corresponding to the minimum cut set. The first shutdown signal is the first shutdown signal triggered, the first safety level channel signal is the first safety level channel signal or a combination of signals triggered, and in the fault tree, the shutdown signal is the top event signal, the safety level channel signal is the intermediate event signal, and the non-safety level logic signal is the bottom event signal.

[0019] The second determining module is used to determine the key event sequence associated with the non-safety logic signal obtained in the first step according to the fault knowledge base. The fault knowledge base includes multiple key event sequences, the triggering location of the key events, and the real-time status of important equipment.

[0020] The interaction layer is used to generate a source map and event report based on the key event sequence corresponding to the unexpected event, and push them to the associated account.

[0021] In one possible implementation, the system further includes a support layer and a data analysis layer;

[0022] The support layer is used to acquire and store DCS configuration files;

[0023] The data analysis layer is used to parse the safety-level DCS configuration file of the support layer to obtain the minimum cut set that triggers each shutdown signal. Among them, a single signal corresponding to a logic OR gate is a minimum cut set, and a group of signals corresponding to a logic AND gate is a minimum cut set. Based on the minimum cut set that triggers each shutdown signal, a two-layer fault tree is constructed with the shutdown signal as the top event and the safety-level channel logic signal as the bottom event, and the combination of minimum cut sets of safety-level logic channel signals as the top event and the non-safety-level logic signals and associated fault knowledge base as the bottom events.

[0024] In one possible implementation, the support layer is also used to acquire and store DCS log files;

[0025] The data analysis layer is also used to analyze the log format and rules of DCS log files, classify and grade log entries according to equipment level and protection function level information, and combine the signal transmission relationship in the control logic to analyze and extract key event sequences, locate the triggering position of key events and the real-time status of important equipment, and build a fault knowledge base.

[0026] In one possible implementation, the second determining module includes:

[0027] The determination submodule is used to determine the correlation between output changes and input changes in the control algorithm based on the operation rules of the encapsulated control module of the DCS system when analyzing and tracing the source of key events based on the key event sequence. Based on this correlation, the key event sequence associated with non-safety logic signals is determined.

[0028] According to another aspect of the present disclosure, a non-volatile computer-readable storage medium is provided, on which computer program instructions are stored, which, when executed by a processor, implement the above-described method.

[0029] The beneficial effects of this disclosed DCS event tracing system based on control logic analysis are as follows:

[0030] 1. After an unexpected event occurs, it can quickly identify the initial signal of the event, conduct tracing analysis of the cause of the event, including possible factors such as equipment / system failure, malfunction and personnel operation, provide analysis results, provide technical reference for event analysts, greatly reduce the workload of manual analysis, and improve the efficiency and accuracy of event tracing.

[0031] 2. This method derives a conditional rule base from the control logic parsing of the DCS configuration, and constructs an event knowledge base based on historical power plant data and operational knowledge. The combination of these two elements makes the source tracing analysis results more meaningful. Furthermore, the source tracing graph directly displays the entire process from the occurrence of an event to its impact, facilitating post-event improvement measures and experience feedback from maintenance personnel. For events involving human error, it can also be used for personnel evaluation, enabling refined overall operation and maintenance management of the nuclear power plant. Thus, by utilizing digital technology, it achieves rapid event data collection, retrieval, and display, as well as intelligent tracing of event causes. This allows for the rapid identification of the initial cause of an event, accelerates human intervention, assists maintenance personnel in analyzing the fault process, and generates improvement measures and experience feedback, thereby improving the efficiency and quality of event source tracing. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of a DCS event tracing system based on control logic parsing, according to an exemplary embodiment.

[0033] Figure 2 This is a schematic diagram of a fault tree according to an exemplary embodiment.

[0034] Figure 3 This is a flowchart illustrating a DCS event tracing method based on control logic parsing, according to an exemplary embodiment. Detailed Implementation

[0035] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] Figure 1This is a schematic diagram illustrating a DCS event tracing system based on control logic parsing, according to an exemplary embodiment. For example... Figure 1 As shown, the system includes a computation layer and an interaction layer;

[0037] The computation layer includes: an acquisition module, a first determination module, and a second determination module;

[0038] The acquisition module is used to read and store shutdown signals, safety-level channel signals and non-safety-level logic signals from the DCS system in real time.

[0039] The first determining module is used to determine the first shutdown signal from the stored shutdown signals when an unexpected event is detected at the nuclear power plant, determine the minimum cut set of the first safety level logic channel signal corresponding to the first shutdown signal according to the fault tree, and determine the non-safety logic signal corresponding to the minimum cut set. The first shutdown signal is the first shutdown signal triggered, the first safety level channel signal is the first safety level channel signal or a combination of signals triggered, and in the fault tree, the shutdown signal is the top event signal, the safety level channel signal is the intermediate event signal, and the non-safety level logic signal is the bottom event signal.

[0040] The second determining module is used to determine the key event sequence associated with the non-safety logic signal obtained in the first step according to the fault knowledge base. The fault knowledge base includes multiple key event sequences, the triggering location of the key events, and the real-time status of important equipment.

[0041] The interaction layer is used to generate a source map and event report based on the key event sequence corresponding to the unexpected event, and push them to the associated account.

[0042] In one possible implementation, such as Figure 1 The system described also includes: a support layer and a data analysis layer;

[0043] The support layer is used to acquire and store DCS configuration files;

[0044] The data analysis layer is used to parse the safety-level DCS configuration file from the support layer. The parsed file contains control configuration information, including encapsulated control module types, basic AND, OR, and NOT logic calculations, and variable connection relationships, thus clarifying the signal transmission relationships of the control logic. It obtains the minimum cut set that triggers each shutdown signal, where a single signal corresponding to an OR gate is the minimum cut set, and a group of signals corresponding to an AND gate is the minimum cut set. Based on the minimum cut set that triggers each shutdown signal, the channel transmission from safety-level signals to non-safety-level signals is constructed as follows: Figure 2The diagram shows a two-layer fault tree with the shutdown signal as the top event and the safety-level channel logic signal as the bottom event, and the minimum cut set combination of the safety-level logic channel signals as the top event and the non-safety-level logic signals and associated fault knowledge base as the bottom events.

[0045] In one possible implementation, such as Figure 1 As shown, the support layer is also used to acquire and store DCS log files;

[0046] The data analysis layer is also used to analyze the log format and rules of DCS log files, classify and grade log entries according to equipment level and protection function level information, and combine the signal transmission relationship in the control logic to analyze and extract key event sequences, locate the triggering position of key events and the real-time status of important equipment, and build a fault knowledge base.

[0047] In one possible implementation, the second determining module includes:

[0048] The determination submodule is used to identify the correlation between output changes and input changes in the control algorithm during source tracing analysis based on the key event sequence. This is done according to the operational rules of the encapsulated control module in the DCS system. Based on this correlation, the key event sequence associated with non-safety logic signals is then identified. Since reverse engineering the signal flow during source tracing analysis based on key event sequences involves numerous branches, determining the key event sequence associated with non-safety logic signals based on the correlation rules of the encapsulated control module in the DCS system effectively improves the system's matching efficiency.

[0049] Figure 3 This is a flowchart illustrating a DCS event tracing method based on control logic parsing, according to an exemplary embodiment. Figure 3 As shown, the method includes:

[0050] Step 10: Read and store shutdown signals, safety-level channel signals and non-safety-level logic signals from the DCS system in real time;

[0051] Step 11: In the event of an unexpected event at the nuclear power plant, the first shutdown signal is determined from the stored shutdown signals. Based on the fault tree, the minimum cut set of the first safety-level logic channel signal corresponding to the first shutdown signal is determined, and the non-safety logic signal corresponding to the minimum cut set is determined. The first shutdown signal is the first shutdown signal triggered, and the first safety-level channel signal is the first safety-level channel signal or combination signal triggered. In the fault tree, the shutdown signal is the top event signal, the safety-level channel signal is the intermediate event signal, and the non-safety-level logic signal is the bottom event signal.

[0052] Step 12: Based on the fault knowledge base, determine the key event sequence associated with the non-safety logic signal obtained in the previous step. The fault knowledge base includes multiple key event sequences, the triggering location of the key events, and the real-time status of important equipment.

[0053] Step 13: Based on the key event sequence corresponding to the unexpected event, generate a source map and event report, and push them to the associated account.

[0054] In one possible implementation, the method further includes:

[0055] Step 20: Parse the safety-level DCS configuration file to obtain the minimum cut set that triggers each shutdown signal. Among them, a single signal corresponding to a logic OR gate is the minimum cut set, and a group of signals corresponding to a logic AND gate is the minimum cut set. Based on the minimum cut set that triggers each shutdown signal, construct a two-layer fault tree with the shutdown signal as the top event and the safety-level channel logic signal as the bottom event, and the combination of minimum cut sets of safety-level logic channel signals as the top event and non-safety-level logic signals and associated fault knowledge base as the bottom events.

[0056] In one possible implementation, the method further includes:

[0057] Step 30: Analyze the log format and rules of the DCS log file, classify and grade the log entries according to the equipment level and protection function level information, and combine the signal transmission relationship in the control logic to analyze and extract the key event sequence, locate the trigger position of the key event and the real-time status of important equipment, and build a fault knowledge base.

[0058] In one possible implementation, step 12 further includes:

[0059] Step 120: When analyzing and tracing the source of key events based on the sequence of key events, determine the correlation between output changes and input changes in the control algorithm according to the operation rules of the encapsulated control module of the DCS system, and determine the key event sequence associated with non-safety logic signals based on the correlation.

[0060] The methods described above have already been explained in detail in the description of the system described above, and will not be repeated here.

[0061] This disclosure can be a system, method, and / or computer program product. A computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement various aspects of this disclosure.

[0062] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by an instruction execution device. Computer-readable storage media can be, for example—but not limited to—electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination thereof. The computer-readable storage media used herein are not to be construed as transient signals themselves, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or electrical signals transmitted through wires.

[0063] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0064] Computer program instructions used to perform the operations of this disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may execute entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing the status information of the computer-readable program instructions to implement various aspects of this disclosure.

[0065] Various aspects of this disclosure are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0066] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that, when executed by the processor of the computer or other programmable data processing apparatus, they create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing apparatus, and / or other device to operate in a particular manner; thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0067] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0068] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction containing one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than those shown in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0069] The various embodiments of this disclosure have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A DCS event tracing method based on control logic analysis, characterized in that, The method includes: Step 10: Read and store shutdown signals, safety-level channel signals and non-safety-level logic signals from the DCS system in real time; Step 11: In the event of an unexpected event at the nuclear power plant, the first shutdown signal is determined from the stored shutdown signals. Based on the fault tree, the minimum cut set of the first safety-level logic channel signal corresponding to the first shutdown signal is determined, and the non-safety logic signal corresponding to the minimum cut set is determined. The first shutdown signal is the first shutdown signal triggered, and the first safety-level logic channel signal is the first safety-level channel signal or a combination of signals triggered. In the fault tree, the shutdown signal is the top event signal, the safety-level channel signal is the intermediate event signal, and the non-safety-level logic signal is the bottom event signal. Step 12: Based on the fault knowledge base, determine the key event sequence associated with the non-safety logic signal obtained in Step 11. The fault knowledge base includes multiple key event sequences, the triggering location of the key events, and the real-time status of important equipment. Step 13: Based on the key event sequence corresponding to the unexpected event, generate a source map and event report, and push them to the associated account; The method further includes: Step 20: Parse the safety-level DCS configuration file to obtain the minimum cut set that triggers each shutdown signal. Among them, a single signal corresponding to a logic OR gate is the minimum cut set, and a group of signals corresponding to a logic AND gate is the minimum cut set. Based on the minimum cut set that triggers each shutdown signal, construct a two-layer fault tree with the shutdown signal as the top event and the safety-level channel logic signal as the bottom event, and the combination of minimum cut sets of safety-level logic channel signals as the top event and non-safety-level logic signals and associated fault knowledge base as the bottom events. Step 30: Analyze the log format and rules of the DCS log file, classify and grade the log entries according to the equipment level and protection function level information, and combine the signal transmission relationship in the control logic to analyze and extract the key event sequence, locate the trigger position of the key event and the real-time status of important equipment, and build a fault knowledge base.

2. The method according to claim 1, characterized in that, Step 12 also includes: Step 120: When analyzing and tracing the source of key events based on the sequence of key events, determine the correlation between output changes and input changes in the control algorithm according to the operation rules of the encapsulated control module of the DCS system, and determine the key event sequence associated with non-safety logic signals based on the correlation.

3. A DCS event tracing system based on control logic parsing, characterized in that, The system includes a computation layer and an interaction layer; The computation layer includes: an acquisition module, a first determination module, and a second determination module; The acquisition module is used to read and store shutdown signals, safety-level channel signals and non-safety-level logic signals from the DCS system in real time. The first determining module is used to determine the first shutdown signal from the stored shutdown signals when an unexpected event is detected at the nuclear power plant, determine the minimum cut set of the first safety level logic channel signal corresponding to the first shutdown signal according to the fault tree, and determine the non-safety logic signal corresponding to the minimum cut set. The first shutdown signal is the first shutdown signal triggered, the first safety level logic channel signal is the first safety level channel signal or combination signal triggered, and in the fault tree, the shutdown signal is the top event signal, the safety level channel signal is the intermediate event signal, and the non-safety level logic signal is the bottom event signal. The second determining module is used to determine the key event sequence associated with the non-safety logic signal obtained by the first determining module based on the fault knowledge base. The fault knowledge base includes multiple key event sequences, the triggering location of the key events, and the real-time status of important equipment. The interaction layer is used to generate a source map and event report based on the key event sequence corresponding to the unexpected event, and push them to the associated account; The system also includes: a support layer and a data analysis layer; The support layer is used to acquire and store DCS configuration files; The data analysis layer is used to parse the safety-level DCS configuration file of the support layer to obtain the minimum cut set that triggers each shutdown signal. Among them, a single signal corresponding to a logic OR gate is a minimum cut set, and a group of signals corresponding to a logic AND gate is a minimum cut set. Based on the minimum cut set that triggers each shutdown signal, a two-layer fault tree is constructed with the shutdown signal as the top event and the safety-level channel logic signal as the bottom event, and the combination of minimum cut sets of safety-level logic channel signals as the top event and the non-safety-level logic signals and associated fault knowledge base as the bottom events. The support layer is also used to acquire and store DCS log files; The data analysis layer is also used to analyze the log format and rules of DCS log files, classify and grade log entries according to equipment level and protection function level information, and combine the signal transmission relationship in the control logic to analyze and extract key event sequences, locate the triggering position of key events and the real-time status of important equipment, and build a fault knowledge base.

4. The system according to claim 3, characterized in that, The second determining module includes: The determination submodule is used to determine the correlation between output changes and input changes in the control algorithm based on the operation rules of the encapsulated control module of the DCS system when analyzing and tracing the source of key events based on the key event sequence. Based on this correlation, the key event sequence associated with non-safety logic signals is determined.

5. A non-volatile computer-readable storage medium storing computer program instructions thereon, characterized in that, When the computer program instructions are executed by the processor, they implement the method of claim 1 or 2.

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