A safety instrumented system communication method and system based on redundant control bus

Abstract

This invention discloses a communication method and system for a safety instrumented system based on a redundant control bus, relating to the field of industrial automation control technology. The method includes generating safety instrument communication messages and simultaneously sending these messages to a first control bus and a second control bus; identifying the direction of signal strength change and bit error rate change of each bus based on feedback signals from the first and second control buses, forming a first direction combination and a second direction combination; comparing the first direction combination and the second direction combination, and outputting the comparison result of the combination relationship for the current period. This invention achieves accurate perception of the evolution trend and cooperative relationship of bus states, and identifies whether the system should be in a cooperative or divergent evolution mode based on the dynamic correlation of state changes, thus providing a fundamental basis for the dynamic and optimized scheduling of communication resources, and significantly improving the adaptability and foresight of communication management of safety instrumented systems under complex operating conditions.

Description

Technical Field

[0001] This invention relates to the field of industrial automation control technology, and in particular to a communication method and system for a safety instrumented system based on a redundant control bus. Background Technology

[0002] In high-risk industrial sectors such as petrochemicals and power energy, reliable communication of safety instrumented systems is crucial. Currently, the mainstream design is a dual-redundant control bus architecture. Existing redundant communication management technologies typically rely on periodic inspections of bus signals and compare static data such as the absolute value of signal strength and absolute value of bit error rate from a single or short-term sample with preset fixed thresholds to determine link connectivity or make primary / backup switching decisions.

[0003] This detection and management model based on static snapshot data has inherent defects. The industrial field environment is complex and ever-changing, and the communication status of the bus is a continuous dynamic process. The signal strength and bit error rate are always fluctuating. Static data points cannot reflect the dynamic change trend of parameters, nor can they capture the relative relationship between the two redundant buses in the state evolution process.

[0004] Therefore, existing technologies struggle to identify the gradual degradation trend of bus status in the early stages, and are even less able to distinguish whether two buses are in a state of coordinated and healthy parallel evolution or have undergone functional differentiation. This results in a lag in the adjustment of redundancy strategies and a single mode, making it impossible to achieve dynamic resource optimization that is deeply adapted to the real-time communication status. Consequently, this restricts the further improvement of the overall reliability of safety instrumented systems in complex and time-varying environments. Summary of the Invention

[0005] This invention provides a communication method and system for a safety instrumented system based on a redundant control bus, in order to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides a communication method for a safety instrumented system based on a redundant control bus, comprising:

[0007] S1. Generate a safety instrument communication message and send the safety instrument communication message to both the first control bus and the second control bus simultaneously;

[0008] S2. Based on the feedback signals from the first control bus and the second control bus, identify the direction of signal strength change and the direction of bit error rate change of each bus, and form a first direction combination and a second direction combination;

[0009] S3. Compare the first direction combination with the second direction combination, and output the combination relationship comparison result for the current period;

[0010] S4. When the combination relationship comparison results are the same, increment the first persistence count and clear the second persistence count; when the combination relationship comparison results are different, increment the second persistence count and clear the first persistence count.

[0011] S5. When the first duration count reaches the first duration length, the co-evolution mode is triggered; when the second duration count reaches the second duration length, the divergence evolution mode is triggered.

[0012] S6. When in cooperative evolution mode, key security parameter messages are sent simultaneously through the first control bus and the second control bus; when in divergent evolution mode, key security parameter messages are sent through a bus where the signal strength changes in the direction of enhancement and the bit error rate changes in the direction of reduction.

[0013] In S2, forming the first direction combination and the second direction combination includes: associating the signal strength change direction determined for any bus with the bit error rate change direction determined for that bus to form the original direction pair of the bus;

[0014] Perform a logical XOR operation on the two directions in the original direction pair to generate a consistency identifier that indicates whether the two directions are consistent.

[0015] The consistency identifier is bound to the original direction pair. The direction combination with the first type of identifier is defined as the first direction combination, and the direction combination with the second type of identifier is defined as the second direction combination.

[0016] In S5, the first duration is defined by the number of durations in which the comparison results of the combination relationship of multiple consecutive periods are the same, and the second duration is defined by the number of durations in which the comparison results of the combination relationship of multiple consecutive periods are different.

[0017] Preferably, identifying the direction of signal strength change of each bus based on the feedback signals of the first control bus and the second control bus includes:

[0018] Synchronously acquire the first feedback signal of the first control bus and the second feedback signal of the second control bus;

[0019] Analyze the changing patterns of the first feedback signal and dynamically define the analysis window based on the changing patterns;

[0020] Within the analysis window, extract the start and end intensity values ​​of the first and second feedback signals;

[0021] The start and end strength values ​​of the two buses are compared, and the direction of signal strength change of the first control bus and the second control bus is determined according to the positive or negative sign of the comparison result.

[0022] Preferably, identifying the direction of bit error rate change for each bus includes:

[0023] From the feedback signal message, the frame check sequence decoding result and the address field matching result are extracted in parallel and used as the first anomaly indicator and the second anomaly indicator, respectively.

[0024] Based on the first and second anomaly indicators, a mutually exclusive weight relationship between the two is established within the current statistical period;

[0025] Based on the dominant side of the mutual exclusion weight relationship, determine whether the direction of the corresponding bus bit error rate change is increasing or decreasing.

[0026] Preferably, the step of comparing the first directional combination with the second directional combination and outputting the combination relationship comparison result for the current period includes:

[0027] Extract the consistency identifiers bound to the first direction combination and the second direction combination respectively;

[0028] Perform a logical XOR operation on the two extracted consistency identifiers;

[0029] The result of the logical XOR operation is concatenated with the historical comparison result sequence to obtain the combination relationship comparison result for the current period.

[0030] Preferably, the step of triggering entry into a co-evolution mode when the first duration count reaches a first duration length, and triggering entry into a divergent evolution mode when the second duration count reaches a second duration length, includes:

[0031] The results of comparing the combination relationships of the current cycle and the outputs of consecutive preceding cycles are arranged into a time-series relationship sequence.

[0032] In the sequence of identified temporal relationships, the symbol representing the consistency of the states of the two buses first forms the starting point of a continuous and stable segment;

[0033] When the symbols corresponding to the starting points indicate consistency, it is determined that the co-evolution mode should be entered; when the symbols corresponding to the starting points indicate inconsistency, it is determined that the divergent evolution mode should be entered.

[0034] Preferably, triggering entry into the co-evolutionary mode or the divergent evolutionary mode includes:

[0035] The symbols corresponding to the starting point and the attributes of continuous and stable paragraphs are encapsulated into mode switching instructions;

[0036] Based on the mode switching instruction, perform permission status switching operations on the message scheduling queues of the first control bus and the second control bus;

[0037] Inject communication parameter configuration carrying the corresponding evolution mode identifier into the message scheduling queue after the permission state switching operation is completed.

[0038] Preferably, when in cooperative evolution mode, sending key security parameter messages simultaneously via the first control bus and the second control bus includes:

[0039] The key security parameter messages are parsed to obtain the message sequence number and data payload;

[0040] Based on the co-evolution mode identifier and message sequence number, the first verification constructor and the second verification constructor are driven to operate respectively;

[0041] The first checksum is obtained through the first checksum constructor, and the second checksum is obtained through the second checksum constructor, which is suitable for the second control bus.

[0042] A copy of the message with the first checksum attached is sent through the first control bus, and a copy of the message with the second checksum attached is sent through the second control bus.

[0043] Preferably, when in the divergent evolution mode, sending the key security parameter message via a bus where the signal strength changes in an increasing direction and the bit error rate changes in a decreasing direction includes:

[0044] The bus whose signal strength changes in the direction of increase and whose bit error rate changes in the direction of decrease is the target bus;

[0045] The key security parameter messages are parsed to obtain the message sequence number and data payload;

[0046] The third check constructor is driven by the deviation evolution mode identifier, message sequence number and target bus identifier.

[0047] The third checksum is obtained by using the third checksum constructor, which is suitable for the target bus.

[0048] The critical security parameter message with a third checksum attached is sent through the target bus.

[0049] To address the aforementioned problems, the present invention also provides a safety instrumented system communication system based on a redundant control bus, the system comprising:

[0050] The message generation and sending module is used to generate safety instrument communication messages and send the safety instrument communication messages to the first control bus and the second control bus simultaneously.

[0051] The dynamic analysis module is used to identify the direction of signal strength change and bit error rate change of each bus based on the feedback signals of the first control bus and the second control bus, and to form a first direction combination and a second direction combination.

[0052] The direction combination comparison module is used to compare the first direction combination with the second direction combination and output the combination relationship comparison result for the current period.

[0053] The pattern persistence counting module is used to increment the first persistence count and clear the second persistence count when the combination relationship comparison results are the same; and to increment the second persistence count and clear the first persistence count when the combination relationship comparison results are different.

[0054] The evolution mode triggering module is used to trigger the entry into the co-evolution mode when the first duration count reaches the first duration length, the first duration length being defined by the number of duration periods in which the comparison results of the combination relationship of the consecutive multiple periods are the same; and to trigger the entry into the divergence evolution mode when the second duration count reaches the second duration length, the second duration length being defined by the number of duration periods in which the comparison results of the combination relationship of the consecutive multiple periods are different.

[0055] The critical message sending module, when in cooperative evolution mode, sends critical security parameter messages simultaneously through the first control bus and the second control bus; when in divergent evolution mode, it sends critical security parameter messages through a bus where the signal strength changes in the direction of enhancement and the bit error rate changes in the direction of reduction.

[0056] The formation of the first direction combination and the second direction combination includes: associating the direction of signal strength change determined for any bus with the direction of bit error rate change determined for that bus to form the original direction pair of the bus;

[0057] Perform a logical XOR operation on the two directions in the original direction pair to generate a consistency identifier that indicates whether the two directions are consistent.

[0058] The consistency identifier is bound to the original direction pair. The direction combination with the first type of identifier is defined as the first direction combination, and the direction combination with the second type of identifier is defined as the second direction combination.

[0059] Compared with the prior art, the present invention has the following beneficial effects:

[0060] 1. By dynamically analyzing the changing direction of dual-redundant bus signal strength and bit error rate, and constructing directional combinations accordingly and comparing directional combinations of different buses, the system achieves accurate perception of bus state evolution trends and cooperative relationships. This enables the system to transcend static threshold judgments and identify whether the system is in a cooperative or divergent evolutionary mode based on the dynamic correlation of state changes. This provides a fundamental basis for the dynamic and optimized scheduling of communication resources and significantly improves the adaptability and foresight of safety instrumented systems in communication management under complex operating conditions.

[0061] 2. By introducing logical operations and timing pattern recognition, the signal and bit error rate direction are logically XORed to generate an embedded consistency identifier. Combined with historical sequence identification of continuous stable segments to trigger mode switching, the synergistic effect of these features makes the system's judgment of coordination and divergence modes more accurate and reliable. This achieves deep adaptation between communication protection strategies and real-time bus status, ensuring high reliability while improving the utilization efficiency of communication resources and the survivability of critical message transmission. Attached Figure Description

[0062] Figure 1 A flowchart of a communication method for a safety instrumented system based on a redundant control bus provided by the present invention;

[0063] Figure 2 A module structure diagram of a safety instrument system communication system based on a redundant control bus is provided for this invention.

[0064] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0065] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0066] Example 1, referring to Figure 1 The diagram shown is a flowchart illustrating a communication method for a safety instrumented system based on a redundant control bus, according to an embodiment of the present invention. In this embodiment, the communication method for a safety instrumented system based on a redundant control bus includes:

[0067] S1. Generate a safety instrument communication message and send the safety instrument communication message to both the first control bus and the second control bus simultaneously;

[0068] S2. Based on the feedback signals from the first control bus and the second control bus, identify the direction of signal strength change and the direction of bit error rate change of each bus, and form a first direction combination and a second direction combination;

[0069] S3. Compare the first direction combination with the second direction combination, and output the combination relationship comparison result for the current period;

[0070] S4. When the combination relationship comparison results are the same, increment the first persistence count and clear the second persistence count; when the combination relationship comparison results are different, increment the second persistence count and clear the first persistence count.

[0071] S5. When the first duration count reaches the first duration length, the co-evolution mode is triggered; when the second duration count reaches the second duration length, the divergence evolution mode is triggered.

[0072] S6. When in cooperative evolution mode, key security parameter messages are sent simultaneously through the first control bus and the second control bus; when in divergent evolution mode, key security parameter messages are sent through a bus where the signal strength changes in the direction of enhancement and the bit error rate changes in the direction of reduction.

[0073] In this embodiment of the invention, a safety instrument communication message is generated and simultaneously sent to the first control bus and the second control bus.

[0074] Specifically, taking the safety instrumented system of a petrochemical production unit as an application scenario, for example, collecting the real-time pressure of the reactor (3.5 MPa) and the real-time temperature of the distillation column (120°C) of the unit, integrating the parameter data, message sending time (202601301000), and sending identifier according to a fixed message structure, and generating a safety instrumented communication message. This message is specifically used to transmit the core safety process parameters of the unit, ensuring the accuracy and relevance of parameter transmission.

[0075] The generated safety instrument communication messages are then connected to the sending ports of the first and second control buses respectively, triggering the synchronous sending action of the two buses. The sending timing is strictly consistent to ensure that the messages are sent from the two redundant buses at the same time.

[0076] For example, after triggering the send command, it is stipulated that both buses complete the first frame transmission of the message within 1000 milliseconds to achieve dual redundancy transmission of the message.

[0077] In this embodiment of the invention, identifying the direction of signal strength change of each bus based on the feedback signals of the first control bus and the second control bus includes:

[0078] Synchronously acquire the first feedback signal of the first control bus and the second feedback signal of the second control bus;

[0079] Analyze the changing patterns of the first feedback signal and dynamically define the analysis window based on the changing patterns;

[0080] Within the analysis window, extract the start and end intensity values ​​of the first and second feedback signals;

[0081] The start and end strength values ​​of the two buses are compared, and the direction of signal strength change of the first control bus and the second control bus is determined according to the positive or negative sign of the comparison result.

[0082] Specifically, the safety instrumented system of a petrochemical production unit can be selected as the application scenario. In this scenario, the first control bus (bus A) and the second control bus (bus B) are both used to transmit feedback signals of key safety parameters such as reactor pressure and distillation column temperature.

[0083] The first feedback signal of bus A and the second feedback signal of bus B are collected synchronously. For example, the strength of the reactor pressure feedback signal at three consecutive sampling points on bus A is 2.1V, 2.3V and 2.5V respectively, and the strength of the reactor pressure feedback signal at three consecutive sampling points on bus B is 1.9V, 2.0V and 2.2V respectively.

[0084] Furthermore, the change pattern of the first feedback signal is analyzed. The signal exhibits a continuous and stable increasing change pattern. Based on this change pattern, the analysis window is dynamically defined as the most recent 3 sampling periods. The duration of the analysis window is preset to 300 milliseconds. The preset basis is that the conventional sampling frequency of the safety instrument feedback signal in this petrochemical production unit scenario is 10 Hz. This duration can fully capture the effective change trend of the signal without missing key signal change data due to an excessively long window.

[0085] Furthermore, within the defined analysis window, the starting strength value of the first feedback signal is extracted as 2.1V and the ending strength value as 2.5V, while the starting strength value of the second feedback signal is extracted as 1.9V and the ending strength value as 2.2V. The extracted starting and ending strength values ​​are the actual signal strength detection values ​​of the first and last sampling points of the corresponding bus within the analysis window.

[0086] Furthermore, the difference between the termination strength value and the starting strength value of each of the two buses is calculated, and the direction of signal strength change is determined according to the sign of the calculation result. If the result of the calculation of the termination strength value minus the starting strength value is positive, the direction of signal strength change of the corresponding bus is determined to be strengthening; if the result is negative, the direction of signal strength change of the corresponding bus is determined to be weakening.

[0087] For example, if the calculated result for bus A is 0.4V, which is a positive value, then the direction of the signal strength change for bus A is determined to be increasing. If the calculated result for bus B is 0.3V, which is a positive value, then the direction of the signal strength change for bus B is determined to be increasing.

[0088] In this embodiment of the invention, identifying the direction of bit error rate change for each bus includes:

[0089] From the feedback signal message, the frame check sequence decoding result and the address field matching result are extracted in parallel and used as the first anomaly indicator and the second anomaly indicator, respectively.

[0090] Based on the first and second anomaly indicators, a mutually exclusive weight relationship between the two is established within the current statistical period;

[0091] Based on the dominant side of the mutual exclusion weight relationship, determine whether the direction of the corresponding bus bit error rate change is increasing or decreasing.

[0092] Specifically, from the messages of the feedback signals from bus A and bus B, the frame check sequence decoding result and the address field matching result are extracted in parallel. The frame check sequence decoding result is used as the first anomaly indicator, and the address field matching result is used as the second anomaly indicator.

[0093] For example, the frame check sequence decoding result of bus A is "check passed" and the address field matching result is "match successful", while the frame check sequence decoding result of bus B is "check failed once" and the address field matching result is "match successful".

[0094] Furthermore, based on the first and second anomaly indicators, a mutually exclusive weight relationship between the two is established within the current statistical period. The current statistical period is preset to 1 second, based on the regular period for bit error rate statistics in this petrochemical production unit scenario. At the same time, the weight of the frame check sequence decoding result is set to 0.6, and the weight of the address field matching result is set to 0.4. The weight setting is based on the fact that the frame check sequence has a higher accuracy in identifying message errors than the address field matching, and after multiple rounds of actual measurement and calibration in this scenario, it has been confirmed that the weight ratio can accurately reflect the actual correlation between the two types of indicators and the bit errors.

[0095] Furthermore, the direction of the bit error rate change of the corresponding bus is determined based on the dominant party of the mutual exclusion weight relationship. The weight ratio of the first anomaly indication and the second anomaly indication is compared, and the party with the higher weight ratio is the dominant party of the mutual exclusion weight relationship.

[0096] Then, the direction of the bit error rate change is determined by combining the instructions from the leading party. If the leading party indicates no abnormality, the direction of the bit error rate change is determined to be decreasing. If the leading party indicates an abnormality, the direction of the bit error rate change is determined by combining the change in the number of abnormalities. If the number of abnormalities decreases, the direction of the bit error rate change is determined to be decreasing. If the number of abnormalities increases, the direction of the bit error rate change is determined to be increasing.

[0097] For example, if the frame check sequence decoding result in bus A is the dominant one with a weight of 0.6 and there is no abnormality, then the direction of the bit error rate change in bus A is determined to be decreasing. If the frame check sequence decoding result in bus B is the dominant one with a weight of 0.6 and the number of check failures is reduced by 1 compared to the previous cycle, then the direction of the bit error rate change in bus B is determined to be decreasing.

[0098] In this embodiment of the invention, forming a first directional combination and a second directional combination includes:

[0099] The direction of signal strength change determined for any bus is associated with the direction of bit error rate change determined for that bus to form the original direction pair for that bus.

[0100] Perform a logical XOR operation on the two directions in the original direction pair to generate a consistency identifier that indicates whether the two directions are consistent.

[0101] Bind the consistency flag to the original direction pair, and output the direction combination corresponding to the bus;

[0102] Among them, the direction combination with the binding result of the first type of identifier is defined as the first direction combination, and the direction combination with the binding result of the second type of identifier is defined as the second direction combination.

[0103] The original direction pair of the bus is represented as follows:

[0104]

[0105] The consistency identifier is defined as:

[0106]

[0107] In the formula, This indicates that the original direction is correct. Indicates a consistency identifier. Indicates the direction of signal strength change. The direction of the change in bit error rate is a variable. Represents the logical XOR operation, when When, it indicates that the two directions are the same; when When, it indicates that the two directions are inconsistent.

[0108] Specifically, the direction of signal strength change determined for any bus is associated one-to-one with the direction of bit error rate change determined for that bus to form the original direction pair for that bus. The original direction pair is presented in the form of signal strength change direction first and bit error rate change direction second. For bus A, the direction of signal strength change is associated with the direction of bit error rate change is associated with the direction of bit error rate change is associated to form the original direction pair for bus A. For bus B, the direction of signal strength change is associated with the direction of bit error rate change is associated with the direction of bit error rate change is associated to form the original direction pair for bus B.

[0109] Furthermore, a logical XOR operation is performed on the two directions in the original direction pair. The specific implementation of the logical XOR operation is to determine whether the direction of signal strength change in the original direction pair is consistent with the direction of bit error rate change. If the change trends of the two directions are inconsistent, the generated consistency flag is 1; if the change trends of the two directions are consistent, the generated consistency flag is 0.

[0110] Specifically, a logical XOR operation can be performed on the two directions in the original direction pair. The specific implementation of the logical XOR operation is to determine whether the changing trends of the signal strength and the bit error rate in the original direction pair are consistent. The core significance of this operation is to determine whether the changes in signal strength and bit error rate on the same bus show a synchronous trend. When the changing trends are not synchronous, the consistency flag is 1, and when the changing trends are synchronous, the consistency flag is 0. That is, a consistency flag of 1 indicates that the current communication state of the bus needs to be focused on, and a consistency flag of 0 indicates that the current communication state of the bus is stable.

[0111] Specifically, this operation is determined by combining the original direction pairs of bus A and bus B. If the two directions in the original direction pair of bus A have inconsistent trends, a consistency flag of 1 is generated. If the two directions in the original direction pair of bus B have inconsistent trends, a consistency flag of 1 is generated.

[0112] Furthermore, the generated consistency identifier is bound to the corresponding original direction pair, with the consistency identifier first and the original direction pair second. After binding, the output is the direction combination corresponding to the bus. After binding the consistency identifier 1 of bus A with the original direction pair, the output is the direction combination of bus A. After binding the consistency identifier 1 of bus B with the original direction pair, the output is the direction combination of bus B.

[0113] Finally, the first type of identifier can be preset to 1 and the second type of identifier to 0. The preset basis is that the judgment priority of communication status abnormality in this petrochemical production device scenario is higher than that of normal status. The direction combination with the binding result of the first type of identifier is defined as the first direction combination, and the direction combination with the binding result of the second type of identifier is defined as the second direction combination. The direction combinations of bus A and bus B are both bound to the first type of identifier 1. Therefore, the direction combinations of bus A and bus B are both the first direction combination.

[0114] In summary, this solution ensures the accuracy of signal strength change identification through dynamically adaptable analysis windows, improves the reliability of bit error rate change direction determination by leveraging mutually exclusive weight relationships, and achieves a comprehensive characterization of bus communication status through direction combinations. It fully utilizes feedback data from redundant buses to achieve dual-dimensional status monitoring, and completes the condensation and integration of status information through logical operations, effectively avoiding the one-sidedness of single-dimensional judgment. This provides accurate and comprehensive decision-making basis for subsequent bus status comparison and communication mode switching, significantly improving the stability and security of safety instrumented system communication and ensuring the accuracy of critical safety parameter transmission.

[0115] In this embodiment of the invention, comparing the first directional combination with the second directional combination and outputting the combination relationship comparison result for the current period includes:

[0116] Extract the consistency identifiers bound to the first direction combination and the second direction combination respectively;

[0117] Perform a logical XOR operation on the two extracted consistency identifiers;

[0118] The result of the logical XOR operation is concatenated with the historical comparison result sequence to obtain the combination relationship comparison result for the current period.

[0119] Specifically, taking the safety instrument system of a petrochemical production unit as an application scenario, the consistency identifiers bound to each bus can be extracted from the first direction combination corresponding to bus A and the first direction combination corresponding to bus B in this scenario.

[0120] For example, the consistency identifier bound in the first direction combination of bus A is 1, and the consistency identifier bound in the first direction combination of bus B is 1. The extracted consistency identifiers are the core identifiers used in the corresponding direction combinations to characterize whether the trend of signal strength and bit error rate changes are consistent.

[0121] Furthermore, a logical XNOR operation is performed on the two extracted consistency identifiers. The specific method of the logical XNOR operation is to determine whether the values ​​of the two consistency identifiers are the same. If the values ​​of the two consistency identifiers are the same, the operation result is 1; if the values ​​of the two consistency identifiers are different, the operation result is 0.

[0122] The core significance of this operation is to determine whether the communication status change trends of the two redundant control buses in the petrochemical production unit scenario are consistent. An operation result of 1 indicates that the status change trends of the two buses are consistent, while an operation result of 0 indicates that the status change trends of the two buses are inconsistent.

[0123] Specifically, the determination operation is performed based on the two consistency identifiers extracted above. Since both values ​​are 1 and the determination results are the same, the logical XOR operation result is 1.

[0124] Finally, the result of this logical XOR operation is concatenated with the historical comparison result sequence stored in the safety instrument system of the petrochemical production unit. The historical comparison result sequence can be an ordered sequence composed of the logical XOR operation results of the previous 5 statistical periods in this scenario.

[0125] For example, if the historical comparison result sequence is 1, 1, 0, 1, 1, then appending the current result 1 to the end of the sequence will result in a new ordered sequence 1, 1, 0, 1, 1, 1. This new sequence is the combination relationship comparison result for the current period. This result fully contains the comparison information of the communication status change trend of the two buses in the current and previous periods.

[0126] Overall, this solution focuses on the core representation dimensions of bus communication status, accurately compares the status change trends of two redundant buses through logical XOR operations, and eliminates the random interference of single-cycle data; at the same time, it combines historical data sequence splicing to completely preserve the temporal evolution information of bus status and avoids deviations caused by isolated judgments.

[0127] This design achieves both high efficiency in bus state comparison and comprehensiveness and reliability of results, providing accurate and continuous decision-making basis for subsequent continuous counting and communication mode switching. It effectively improves the response sensitivity of the safety instrument system to changes in bus state and further ensures the stability and security of key safety parameter transmission.

[0128] In this embodiment of the invention, when the combination relationship comparison results are the same, the first continuous count is incremented and the second continuous count is cleared; when the combination relationship comparison results are different, the second continuous count is incremented and the first continuous count is cleared.

[0129] Specifically, first determine the attributes of the current cycle combination relationship comparison results. The judgment criteria are that if the logical XOR operation results in the comparison results are consecutively 1, they are the same; if there are different values, they are different. For example, if the current comparison results are 1, 1, 0, 1, 1, 1, they are judged to be the same.

[0130] If the results are the same, increment the first continuous count by 1. The initial value of the first continuous count is 0, and it becomes 1 after incrementing. At the same time, set the value of the second continuous count to 0. The initial value of the second continuous count is 0.

[0131] When the results are different, the second continuous count is incremented by 1, and the value of the first continuous count is set to 0. This operation is triggered only when there are different values ​​in the comparison results.

[0132] In this embodiment of the invention, when the first duration count reaches the first duration length, a co-evolution mode is triggered; when the second duration count reaches the second duration length, a divergence evolution mode is triggered, including:

[0133] The results of comparing the combination relationships of the current cycle and the outputs of consecutive preceding cycles are arranged into a time-series relationship sequence.

[0134] In the sequence of identified temporal relationships, the symbol representing the consistency of the states of the two buses first forms the starting point of a continuous and stable segment;

[0135] When the symbols corresponding to the starting points indicate consistency, it is determined that the co-evolution mode should be entered; when the symbols corresponding to the starting points indicate inconsistency, it is determined that the divergent evolution mode should be entered.

[0136] Among them, continuous and stable segments must meet the following requirements:

[0137]

[0138] In the formula, Indicates the first The results of comparing the combination relationships of variables over a period of time The symbol to be detected is currently being tested. The length of a continuous, stable segment is determined automatically by the system through monitoring the stability of the sequence, rather than being preset. Indicates the starting point of a continuous, stable paragraph. Mathematical criteria for determining paragraph stability. This indicates the continuous periodic interval corresponding to a continuous stable segment.

[0139] When the starting point Corresponding symbols When the indications are consistent, the decision should be made to enter the co-evolution mode; when the indications are inconsistent, the decision should be made to enter the divergent evolution mode.

[0140] In this invention, the first duration length refers to the number of consecutive cycles in which the comparison results of the combined relationships are the same. This duration length can be an adaptive value dynamically determined based on the actual communication state, for example, automatically confirmed by the system by monitoring the stability of the comparison results of the combined relationships. In some implementation scenarios, it can also be preset to a fixed value, such as 3 cycles. When the first duration count accumulates to the first duration length, it means that the communication state of the two buses has formed a stable "co-evolution" trend.

[0141] Accordingly, the second duration refers to the number of consecutive periods in which the comparison results of the combined relationships are all different, and its value is determined in the same way as the first duration. When the second duration count accumulates to the second duration, it means that the communication states of the two buses have formed a stable divergence evolution trend.

[0142] Those skilled in the art will understand that the specific value of the duration can be set or adjusted based on factors such as the environmental noise level of the actual industrial site and the stability requirements of bus communication. For example, in environments with strong electromagnetic interference, the duration can be appropriately increased to avoid frequent mode switching due to transient interference; in safety interlock scenarios requiring rapid response, the duration can be appropriately shortened to improve the system's sensitivity to changes in bus status. These settings are all equivalent embodiments of the present invention, and together with the aforementioned formula for identifying continuous stable segments, they constitute the complete technical solution of the present invention.

[0143] In this embodiment of the invention, triggering entry into a co-evolutionary mode or a divergent evolutionary mode includes:

[0144] The symbols corresponding to the starting point and the attributes of continuous and stable paragraphs are encapsulated into mode switching instructions;

[0145] Based on the mode switching instruction, perform permission status switching operations on the message scheduling queues of the first control bus and the second control bus;

[0146] Inject communication parameter configuration carrying the corresponding evolution mode identifier into the message scheduling queue after the permission state switching operation is completed.

[0147] Specifically, the comparison results of the combination relationship between the current cycle and the output of the consecutive preceding cycles can be arranged in chronological order to form a time-series relationship sequence.

[0148] For example, if the current cycle is the 6th cycle and the combination relationship comparison result is 1, the comparison results of the previous 5 cycles are 1, 1, 0, 1, 1 respectively. The resulting time sequence is 1, 1, 0, 1, 1, 1. Each value in the sequence corresponds to the communication status comparison result of the two redundant control buses in the petrochemical production unit in the corresponding cycle.

[0149] Furthermore, the numerical values ​​in the time-series relationship sequence can be checked bit by bit to identify the starting point of the first continuous stable segment where the symbol representing the consistency of the two bus states is formed. The method for determining a continuous stable segment is that there is a continuous periodic interval, the combination relationship comparison result of each period in the interval is the same symbol, and the sum of the absolute values ​​of the differences between the symbol and all results in the interval is 0. The segment length is automatically confirmed by the stability of the monitoring sequence.

[0150] For example, in the sequence 1, 1, 0, 1, 1, 1, the symbol representing consistency is 1, and the first continuous stable segment formed is the 4th to 6th cycle. All results in this interval are 1, the sum of the absolute values ​​of the differences is 0, the automatically confirmed segment length is 3, and the corresponding starting point is the 4th cycle.

[0151] Furthermore, the bus state indicated by the symbol corresponding to the starting point can be determined. If the symbol corresponding to the starting point is 1, which represents consistency, it is determined that the co-evolution mode should be entered. If the symbol corresponding to the starting point is 0, which represents inconsistency, it is determined that the divergent evolution mode should be entered.

[0152] For example, in this embodiment, the symbol corresponding to the 4th cycle of the starting point is 1, indicating consistency, so it is determined that the co-evolution mode should be entered.

[0153] Furthermore, the symbols corresponding to the starting point and the attributes of continuous and stable paragraphs are encapsulated into mode switching instructions, wherein the attributes of continuous and stable paragraphs include the automatically confirmed paragraph length and the corresponding continuous period interval.

[0154] For example, the encapsulated mode switching instruction contains symbol 1, paragraph length 3, and period interval 4 to 6. All information in the instruction corresponds to the communication status monitoring data of the redundant control bus of the petrochemical production unit.

[0155] Furthermore, based on the encapsulated mode switching instruction, the permission status switching operation is performed on the message scheduling queues of the first control bus and the second control bus in the petrochemical production unit. The switching operation for the cooperative evolution mode is to open the message scheduling queues of the two buses with equal sending permissions, ensuring that the two buses can simultaneously receive and send key safety parameter messages.

[0156] Finally, after the permission state switching operation is completed, the communication parameter configuration carrying the corresponding evolution mode identifier is injected into the message scheduling queue. For example, for the cooperative evolution mode, the communication parameter configuration carrying the identifier XT is injected. The configuration includes the synchronous transmission timing and data verification standard of key safety parameter messages of petrochemical production unit reactors and distillation columns, ensuring that the two buses perform message transmission operations according to a unified standard.

[0157] In summary, this solution avoids erroneous mode switching caused by single-cycle data through time series analysis and continuous stable segment identification, ensuring the accuracy of mode switching; and achieves a smooth transition and accurate adaptation between the two evolution modes through permission state switching and parameter configuration injection.

[0158] This design ensures efficient and coordinated transmission of redundant buses when the states are consistent, and enables rapid switching to the optimal transmission strategy when the states diverge, significantly improving the adaptability and reliability of safety instrumented system communication and providing strong support for the stable transmission of critical safety parameters.

[0159] In this embodiment of the invention, when in cooperative evolution mode, key security parameter messages are sent simultaneously via the first control bus and the second control bus, including:

[0160] The key security parameter messages are parsed to obtain the message sequence number and data payload;

[0161] Based on the co-evolution mode identifier and message sequence number, the first verification constructor and the second verification constructor are driven to operate respectively;

[0162] The first checksum is obtained through the first checksum constructor, and the second checksum is obtained through the second checksum constructor, which is suitable for the second control bus.

[0163] A copy of the message with the first checksum attached is sent through the first control bus, and a copy of the message with the second checksum attached is sent through the second control bus.

[0164] Specifically, the application scenario can be the safety instrumented system of a petrochemical production unit. In this scenario, when in a collaborative evolution mode, the key safety parameter messages such as reactor pressure and distillation column temperature are parsed segment by segment. The ordered digital code in the message header is extracted as the message sequence number, and the process parameter values ​​in the message data segment are extracted as the data payload. For example, the parsed message sequence number is 20260130001, and the data payload is reactor pressure 3.5MPa and distillation column temperature 120℃.

[0165] Furthermore, based on the co-evolution mode identifier XT and the parsed message sequence number 20260130001, the independent operation of the first verification constructor and the second verification constructor is triggered respectively. The triggering method is to input the mode identifier and sequence number into the information input port of the corresponding constructor in a fixed format, and drive the constructor to start the verification code generation process.

[0166] Furthermore, the first verification constructor encodes the input mode identifier, serial number, and data payload to generate a first verification code adapted to the first control bus of the petrochemical production unit, for example, the hexadecimal code 3E7A. The second verification constructor generates a second verification code adapted to the second control bus using the same encoding rules, for example, the hexadecimal code 8B2F.

[0167] Furthermore, a copy of the key security parameter message with the first check code 3E7A attached can be sent through the first control bus, while a copy of the message with the second check code 8B2F attached can be sent through the second control bus. The sending actions are triggered synchronously to ensure that the two buses complete the message transmission at the same time.

[0168] In this embodiment of the invention, when in a divergent evolution mode, key security parameter messages are sent via a bus where the signal strength changes in an increasing direction and the bit error rate changes in a decreasing direction, including:

[0169] The bus whose signal strength changes in the direction of increase and whose bit error rate changes in the direction of decrease is the target bus;

[0170] The key security parameter messages are parsed to obtain the message sequence number and data payload;

[0171] The third check constructor is driven by the deviation evolution mode identifier, message sequence number and target bus identifier.

[0172] The third checksum is obtained by using the third checksum constructor, which is suitable for the target bus.

[0173] The critical security parameter message with a third checksum attached is sent through the target bus.

[0174] Specifically, in the scenario where the evolution mode is diverging, the signal strength and bit error rate change direction of the first control bus and the second control bus are checked. The bus that simultaneously satisfies the condition that the signal strength change direction is increasing and the bit error rate change direction is decreasing is determined as the target bus. For example, after checking, the first control bus is determined as the target bus.

[0175] Furthermore, the critical safety parameter messages of the petrochemical production unit are parsed, and the message sequence number and data payload of the data segment are extracted according to the message structure. For example, the message sequence number 20260130002 is obtained and the data payload is the reactor pressure of 3.6MPa and the distillation column temperature of 118℃.

[0176] Furthermore, based on the deviation evolution mode identifier BL, the parsed message sequence number 20260130002, and the target bus identifier ZX01, the three types of information are input into the input port of the third check constructor in a specified format, driving the third check constructor to start the dedicated check code generation process.

[0177] Furthermore, the third check constructor performs joint encoding operations on the input mode identifier, serial number, target bus identifier, and data payload to generate a third check code adapted to the target bus, such as the hexadecimal code 5D9C.

[0178] Finally, the key security parameter message with the third check code 5D9C attached is sent separately through the established first control bus. The transmission process completes the frame-by-frame transmission of the message according to the timing requirements of the device's secure communication.

[0179] In summary, this solution adapts differentiated transmission strategies to different bus states. In cooperative mode, it utilizes dual-bus synchronous transmission to improve the redundancy and reliability of key parameter transmission, while in divergent mode, it selects the optimal bus to ensure transmission quality. At the same time, it uses dedicated check codes to adapt to different bus characteristics and reduce the risk of transmission errors.

[0180] This design fully leverages the collaborative advantages of redundant buses and can accurately select the optimal path when the bus state is differentiated, significantly improving the stability, accuracy, and adaptability of key parameter transmission in safety instrumented systems and ensuring the effective transmission of safety control commands in industrial scenarios.

[0181] Example 2, as Figure 2 The diagram shown is a module structure diagram of a safety instrumented system communication system based on a redundant control bus provided by the present invention, which includes:

[0182] The message generation and sending module 101 is used to generate safety instrument communication messages and send the safety instrument communication messages to the first control bus and the second control bus simultaneously.

[0183] The dynamic analysis module 102 is used to identify the direction of signal strength change and the direction of bit error rate change of each bus based on the feedback signals of the first control bus and the second control bus, and to form a first direction combination and a second direction combination.

[0184] The direction combination comparison module 103 is used to compare the first direction combination with the second direction combination and output the combination relationship comparison result for the current period.

[0185] The pattern persistence counting module 104 is used to increment the first persistence count and clear the second persistence count when the combination relationship comparison results are the same; and to increment the second persistence count and clear the first persistence count when the combination relationship comparison results are different.

[0186] The evolution mode triggering module 105 is used to trigger the entry into the co-evolution mode when the first duration count reaches the first duration length, the first duration length being defined by the number of duration periods in which the comparison results of the combination relationship of the consecutive multiple periods are the same; and to trigger the entry into the divergence evolution mode when the second duration count reaches the second duration length, the second duration length being defined by the number of duration periods in which the comparison results of the combination relationship of the consecutive multiple periods are different.

[0187] The key message sending module 106, when in cooperative evolution mode, sends key security parameter messages simultaneously through the first control bus and the second control bus; when in divergent evolution mode, it sends key security parameter messages through a bus where the signal strength changes in the direction of enhancement and the bit error rate changes in the direction of reduction.

[0188] The formation of the first direction combination and the second direction combination includes: associating the direction of signal strength change determined for any bus with the direction of bit error rate change determined for that bus to form the original direction pair of the bus;

[0189] Perform a logical XOR operation on the two directions in the original direction pair to generate a consistency identifier that indicates whether the two directions are consistent.

[0190] The consistency identifier is bound to the original direction pair. The direction combination with the first type of identifier is defined as the first direction combination, and the direction combination with the second type of identifier is defined as the second direction combination.

[0191] In the several embodiments provided by this invention, it should be understood that the disclosed methods and systems can be implemented in other ways. For example, the system embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and other division methods may be used in actual implementation.

[0192] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0193] Furthermore, the functional modules in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or in the form of hardware plus software functional modules.

[0194] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0195] The embodiments of this application can acquire and process relevant data based on artificial intelligence technology. Artificial intelligence is the theory, method, technology, and application system that uses digital computers or machines controlled by digital computers to simulate, extend, and expand human intelligence, perceive the environment, acquire knowledge, and use that knowledge to obtain optimal results.

[0196] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A communication method for a safety instrumented system based on a redundant control bus, characterized in that, The method includes: S1. Generate a safety instrument communication message and send the safety instrument communication message to both the first control bus and the second control bus simultaneously; S2. Based on the feedback signals from the first control bus and the second control bus, identify the direction of signal strength change and the direction of bit error rate change of each bus, and form a first direction combination and a second direction combination; The difference between the termination strength value and the starting strength value of each of the two buses is calculated, and the direction of signal strength change is determined according to the sign of the calculation result. If the result of the calculation of the termination strength value minus the starting strength value is positive, the direction of signal strength change of the corresponding bus is determined to be strengthening; if the result is negative, the direction of signal strength change of the corresponding bus is determined to be weakening. The direction of the bit error rate change of the corresponding bus is determined based on the dominant party of the mutual exclusion weight relationship. The weight ratio of the first anomaly indicator and the second anomaly indicator is compared, and the party with the higher weight ratio is the dominant party of the mutual exclusion weight relationship. Then, the direction of the bit error rate change is determined by combining the instructions from the leading party. If the leading party indicates no abnormality, the direction of the bit error rate change is determined to be decreasing. If the leading party indicates an abnormality, the direction of the bit error rate change is determined by combining the change in the number of abnormalities. If the number of abnormalities decreases, the direction of the bit error rate change is determined to be decreasing. If the number of abnormalities increases, the direction of the bit error rate change is determined to be increasing. The direction of signal strength change determined for any bus is associated with the direction of bit error rate change determined for that bus to form the original direction pair for that bus. Perform a logical XOR operation on the two directions in the original direction pair to generate a consistency identifier that indicates whether the two directions are consistent. Bind the consistency flag to the original direction pair, and output the direction combination corresponding to the bus; Among them, the direction combination with the binding result of the first type of identifier is defined as the first direction combination, and the direction combination with the binding result of the second type of identifier is defined as the second direction combination; S3. Compare the first direction combination with the second direction combination, and output the combination relationship comparison result for the current period; The direction of signal strength change determined for any bus is associated one-to-one with the direction of bit error rate change determined for that bus to form the original direction pair for that bus. The original direction pair is presented in the form of signal strength change direction first and bit error rate change direction second. For bus A, the direction of signal strength change is associated with the direction of bit error rate change is associated with the direction of bit error rate change is associated to form the original direction pair for bus A. For bus B, the direction of signal strength change is associated with the direction of bit error rate change is associated with the direction of bit error rate change is associated to form the original direction pair for bus B. Furthermore, a logical XOR operation is performed on the two directions in the original direction pair. The specific implementation of the logical XOR operation is to determine whether the direction of signal strength change in the original direction pair is consistent with the direction of bit error rate change. If the change trends of the two directions are inconsistent, the generated consistency flag is 1; if the change trends of the two directions are consistent, the generated consistency flag is 0. S4. When the combination relationship comparison results are the same, increment the first persistence count and clear the second persistence count; when the combination relationship comparison results are different, increment the second persistence count and clear the first persistence count. First, determine the attributes of the current cycle combination relationship comparison results. The judgment criteria are that if the logical XOR operation results in the comparison results are consecutively 1, they are the same; if there are different values, they are different. When the determination results are the same, the first continuous count is incremented by 1. The initial value of the first continuous count is 0, and it becomes 1 after being incremented by 1. At the same time, the value of the second continuous count is set to 0. The initial value of the second continuous count is 0. When the results are different, the second continuous count is incremented by 1, and the value of the first continuous count is set to 0. This operation is triggered only when there are different values ​​in the comparison results. S5. When the first duration count reaches the first duration length, the co-evolution mode is triggered; when the second duration count reaches the second duration length, the divergence evolution mode is triggered. The first duration is defined by the number of durations in which the comparison results of the combination relationship of multiple consecutive periods are the same, and the second duration is defined by the number of durations in which the comparison results of the combination relationship of multiple consecutive periods are different. The bus state indicated by the symbol corresponding to the starting point can be determined. If the symbol corresponding to the starting point is 1, which represents consistency, it is determined that the co-evolution mode should be entered. If the symbol corresponding to the starting point is 0, which represents inconsistency, it is determined that the divergent evolution mode should be entered. S6. When in cooperative evolution mode, key security parameter messages are sent simultaneously through the first control bus and the second control bus; when in divergent evolution mode, key security parameter messages are sent through a bus where the signal strength changes in the direction of enhancement and the bit error rate changes in the direction of reduction.

2. The communication method for a safety instrumented system based on a redundant control bus as described in claim 1, characterized in that, The step of identifying the direction of signal strength change of each bus based on the feedback signals of the first and second control buses includes: Synchronously acquire the first feedback signal of the first control bus and the second feedback signal of the second control bus; Analyze the changing patterns of the first feedback signal and dynamically define the analysis window based on the changing patterns; Within the analysis window, extract the start and end intensity values ​​of the first and second feedback signals; The start and end strength values ​​of the two buses are compared, and the direction of signal strength change of the first control bus and the second control bus is determined according to the positive or negative sign of the comparison result.

3. The communication method for a safety instrumented system based on a redundant control bus as described in claim 2, characterized in that, The identification of the direction of bit error rate changes for each bus includes: From the feedback signal message, the frame check sequence decoding result and the address field matching result are extracted in parallel and used as the first anomaly indicator and the second anomaly indicator, respectively. Based on the first and second anomaly indicators, a mutually exclusive weight relationship between the two is established within the current statistical period; Based on the dominant side of the mutual exclusion weight relationship, determine whether the direction of the corresponding bus bit error rate change is increasing or decreasing.

4. The communication method for a safety instrumented system based on a redundant control bus as described in claim 3, characterized in that, The step of comparing the first directional combination with the second directional combination and outputting the combination relationship comparison result for the current period includes: Extract the consistency identifiers bound to the first direction combination and the second direction combination respectively; Perform a logical XOR operation on the two extracted consistency identifiers; The result of the logical XOR operation is concatenated with the historical comparison result sequence to obtain the combination relationship comparison result for the current period.

5. The communication method for a safety instrumented system based on a redundant control bus as described in claim 1, characterized in that, When the first duration count reaches the first duration length, the co-evolution mode is triggered. When the second duration count reaches the second duration length, it triggers entry into the divergence evolution mode, including: The results of comparing the combination relationships of the current cycle and the outputs of consecutive preceding cycles are arranged into a time-series relationship sequence. In the sequence of identified temporal relationships, the symbol representing the consistency of the states of the two buses first forms the starting point of a continuous and stable segment; When the symbols corresponding to the starting points indicate consistency, it is determined that the co-evolution mode should be entered; when the symbols corresponding to the starting points indicate inconsistency, it is determined that the divergent evolution mode should be entered.

6. The communication method for a safety instrumented system based on a redundant control bus as described in claim 5, characterized in that, The triggering of entering the co-evolutionary mode or the divergent evolutionary mode includes: The symbols corresponding to the starting point and the attributes of continuous and stable paragraphs are encapsulated into mode switching instructions; Based on the mode switching instruction, perform permission status switching operations on the message scheduling queues of the first control bus and the second control bus; Inject communication parameter configuration carrying the corresponding evolution mode identifier into the message scheduling queue after the permission state switching operation is completed.

7. The communication method for a safety instrumented system based on a redundant control bus as described in claim 1, characterized in that, When in cooperative evolution mode, the critical security parameter messages are sent simultaneously via the first control bus and the second control bus, including: The key security parameter messages are parsed to obtain the message sequence number and data payload; Based on the co-evolution mode identifier and message sequence number, the first verification constructor and the second verification constructor are driven to operate respectively; The first checksum is obtained through the first checksum constructor, and the second checksum is obtained through the second checksum constructor, which is suitable for the second control bus. A copy of the message with the first checksum attached is sent through the first control bus, and a copy of the message with the second checksum attached is sent through the second control bus.

8. The communication method for a safety instrumented system based on a redundant control bus as described in claim 7, characterized in that, When in the divergent evolution mode, the critical security parameter message is sent via a bus where the signal strength changes in an increasing direction and the bit error rate changes in a decreasing direction, including: The bus whose signal strength changes in the direction of increase and whose bit error rate changes in the direction of decrease is the target bus; The key security parameter messages are parsed to obtain the message sequence number and data payload; The third check constructor is driven by the deviation evolution mode identifier, message sequence number and target bus identifier. The third checksum is obtained by using the third checksum constructor, which is suitable for the target bus. The critical security parameter message with a third checksum attached is sent through the target bus.

9. A communication system for a safety instrumented system based on a redundant control bus, used to implement the communication method for a safety instrumented system based on a redundant control bus as described in any one of claims 1-8, characterized in that, The system includes: The message generation and sending module is used to generate safety instrument communication messages and send the safety instrument communication messages to the first control bus and the second control bus simultaneously. The dynamic analysis module is used to identify the direction of signal strength change and bit error rate change of each bus based on the feedback signals of the first control bus and the second control bus, and to form a first direction combination and a second direction combination. The difference between the termination strength value and the starting strength value of each of the two buses is calculated, and the direction of signal strength change is determined according to the sign of the calculation result. If the result of the calculation of the termination strength value minus the starting strength value is positive, the direction of signal strength change of the corresponding bus is determined to be strengthening; if the result is negative, the direction of signal strength change of the corresponding bus is determined to be weakening. The direction of the bit error rate change of the corresponding bus is determined based on the dominant party of the mutual exclusion weight relationship. The weight ratio of the first anomaly indicator and the second anomaly indicator is compared, and the party with the higher weight ratio is the dominant party of the mutual exclusion weight relationship. Then, the direction of the bit error rate change is determined by combining the instructions from the leading party. If the leading party indicates no abnormality, the direction of the bit error rate change is determined to be decreasing. If the leading party indicates an abnormality, the direction of the bit error rate change is determined by combining the change in the number of abnormalities. If the number of abnormalities decreases, the direction of the bit error rate change is determined to be decreasing. If the number of abnormalities increases, the direction of the bit error rate change is determined to be increasing. The direction of signal strength change determined for any bus is associated with the direction of bit error rate change determined for that bus to form the original direction pair for that bus. Perform a logical XOR operation on the two directions in the original direction pair to generate a consistency identifier that indicates whether the two directions are consistent. Bind the consistency flag to the original direction pair, and output the direction combination corresponding to the bus; Among them, the direction combination with the binding result of the first type of identifier is defined as the first direction combination, and the direction combination with the binding result of the second type of identifier is defined as the second direction combination; The direction combination comparison module is used to compare the first direction combination with the second direction combination and output the combination relationship comparison result for the current period. The direction of signal strength change determined for any bus is associated one-to-one with the direction of bit error rate change determined for that bus to form the original direction pair for that bus. The original direction pair is presented in the form of signal strength change direction first and bit error rate change direction second. For bus A, the direction of signal strength change is associated with the direction of bit error rate change is associated with the direction of bit error rate change is associated to form the original direction pair for bus A. For bus B, the direction of signal strength change is associated with the direction of bit error rate change is associated with the direction of bit error rate change is associated to form the original direction pair for bus B. Furthermore, a logical XOR operation is performed on the two directions in the original direction pair. The specific implementation of the logical XOR operation is to determine whether the direction of signal strength change in the original direction pair is consistent with the direction of bit error rate change. If the change trends of the two directions are inconsistent, the generated consistency flag is 1; if the change trends of the two directions are consistent, the generated consistency flag is 0. The pattern persistence counting module is used to increment the first persistence count and clear the second persistence count when the combination relationship comparison results are the same; and to increment the second persistence count and clear the first persistence count when the combination relationship comparison results are different. First, determine the attributes of the current cycle combination relationship comparison results. The judgment criteria are that if the logical XOR operation results in the comparison results are consecutively 1, they are the same; if there are different values, they are different. When the determination results are the same, the first continuous count is incremented by 1. The initial value of the first continuous count is 0, and it becomes 1 after being incremented by 1. At the same time, the value of the second continuous count is set to 0. The initial value of the second continuous count is 0. When the results are different, the second continuous count is incremented by 1, and the value of the first continuous count is set to 0. This operation is triggered only when there are different values ​​in the comparison results. The evolution mode triggering module is used to trigger the entry into the co-evolution mode when the first duration count reaches the first duration length, and to trigger the entry into the divergent evolution mode when the second duration count reaches the second duration length. The first duration is defined by the number of durations in which the comparison results of the combination relationship of multiple consecutive periods are the same, and the second duration is defined by the number of durations in which the comparison results of the combination relationship of multiple consecutive periods are different. The bus state indicated by the symbol corresponding to the starting point can be determined. If the symbol corresponding to the starting point is 1, which represents consistency, it is determined that the co-evolution mode should be entered. If the symbol corresponding to the starting point is 0, which represents inconsistency, it is determined that the divergent evolution mode should be entered. The critical message sending module is used to send critical security parameter messages simultaneously through the first control bus and the second control bus when in the cooperative evolution mode; and to send critical security parameter messages through a bus in which the signal strength changes in the direction of enhancement and the bit error rate changes in the direction of reduction when in the divergent evolution mode.

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