Thermal power plant cable laying path dynamic optimization method based on three-dimensional model

Abstract

The present application belongs to the technical field of engineering design, and relates to a power plant cable laying path dynamic optimization method based on a three-dimensional model. The present application collects cable attribute values and candidate laying paths of key cables in each preset optimization period, generates a key loop group and a path segment sequence, identifies same-tank centralized values and cross-group centralized values, and generates a common cause failure risk value in combination with a dangerous level value of a bridge path segment; determines a high-risk path segment based on the common cause failure risk value, generates a dispersion constraint condition, updates a path cost of the candidate laying path, and obtains a dispersion optimization path. The present application solves the problem that the existing path optimization only focuses on path length and bridge capacity, and it is difficult to identify the common cause failure risk caused by centralized laying of key protection loops, so that the selection of the candidate laying path simultaneously considers the path cost and the centralized state of the key protection loops in the high-risk path segment.

Description

Technical Field

[0001] This invention relates to the field of engineering design technology, and in particular to a dynamic optimization method for cable laying paths in thermal power plants based on three-dimensional models. Background Technology

[0002] Thermal power plants have a large number of cables, and cable routes typically pass through boiler areas, turbine areas, generator-transformer areas, plant auxiliary power areas, electronics rooms, cable trays, cable shafts, and cable trenches. To improve the efficiency of cable laying design, existing technologies usually establish the path relationships between cable trays, wall penetrations, cable shafts, cable trenches, and control panel access points based on a 3D model of the thermal power plant. Candidate cable laying paths are generated based on the cable's starting and ending points, remaining cable tray capacity, path length, number of turns, spatial obstacle avoidance results, and construction accessibility. The recommended laying path, which is shortest, has sufficient capacity, and is easy to construct, is then selected. However, in the dynamic optimization of actual cable laying paths in thermal power plants, the rationality of cable paths does not solely depend on the path length of individual cables and the capacity of cable trays. Thermal power plants contain critical protection circuits responsible for unit tripping, boiler safety protection, turbine safety protection, generator protection, plant power protection, fire alarm linkage, and interlocking of important equipment. Some critical protection circuits have independent, redundant, or grouped protection relationships, and their laying paths should avoid excessive concentration within the same cable tray segment. Existing path optimization methods based on three-dimensional models typically treat cables as independent path calculation objects, or only apply conventional constraints based on cable type, cable tray layer, and cable tray capacity, failing to further identify the protected objects, protection functions, redundancy relationships, and safety levels among critical cables. When the system prioritizes shortening path length, reducing cable tray occupancy, and improving construction efficiency, turbine protection cables, boiler protection cables, generator-transformer protection cables, plant power protection cables, fire-fighting linkage cables, and critical cables in distributed control systems that perform interlocking protection, trip control, accident alarm, or important equipment interlocking functions are easily concentrated and allocated to the same cable tray path segment. This makes the path generated in the 3D model spatially passable and meets the capacity requirements, but it hides the risk of common cause failure caused by the concentrated laying of critical protection circuits. Especially in the context of commissioning, maintenance, technical upgrades and long-term operation of thermal power plants, the degree of danger of different cable tray routes may change due to the influence of on-site operations and operating environment. For example, in turbine protection scenarios, if multiple turbine trip protection cables are laid together on the same cable tray path, accidental contact during maintenance, mechanical damage, or abnormal cable tray support in that path may simultaneously damage multiple turbine protection signals, affecting the unit's emergency shutdown capability. In boiler protection scenarios, if critical cables related to furnace safety monitoring, combustion interlocking, and flame detection pass through the same cable tray path, a local fire or abnormal hot work operation in that path may cause boiler protection link anomalies, increasing the risk to boiler safe operation. In generator-transformer unit protection and plant power protection scenarios, if multiple protection cables pass through a low-level cable tray path, water ingress, water accumulation, or mechanical damage in that path may cause multiple protection channels to fail simultaneously, affecting the reliability of electrical protection actions. In fire alarm linkage and distributed control system scenarios, if critical interlocking signal cables are laid together on the same main cable tray path, a local fire, cable tray collapse, or accidental cutting during maintenance may cause synchronous anomalies in fire alarms, equipment shutdowns, and interlocking control functions. Therefore, existing methods for optimizing cable laying paths in thermal power plants based on three-dimensional models, if they only pursue path length, cable tray capacity, and construction convenience, without identifying and dynamically correcting the concentration values ​​of critical protection circuits, the hazard level values ​​of cable tray path segments, and the risk values ​​of common causes of failure, will be unable to meet the requirements of key systems in thermal power plants for safe and dispersed cable paths, accident isolation, and reliable operation. Summary of the Invention

[0003] The purpose of this invention is to address the problem that existing methods for optimizing cable laying paths in thermal power plants based on three-dimensional models fail to identify the concentration of critical protection circuits in the same cable tray or across different groups within the same cable tray path segment, leading to the risk of common cause failure under localized accidents. Therefore, this invention proposes a dynamic optimization method for cable laying paths in thermal power plants based on three-dimensional models.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: a dynamic optimization method for cable laying paths in thermal power plants based on a three-dimensional model, comprising the following steps: S1. Collect the cable attribute values ​​and candidate laying paths of key cables in each preset optimization cycle, and generate key loop groups based on the cable attribute values. S2. Based on the candidate laying paths, the candidate laying paths of each critical cable are divided into cable tray path segments to obtain a path segment sequence. S3. Based on the critical loop group and path segment sequence, identify the concentrated value of critical cables in the same tray and the concentrated value across different critical loop groups within the same cable tray path segment to obtain the concentrated value of critical loops. S4. Collect the hazard level value of the cable tray path segment, generate the common cause failure risk value based on the critical loop concentration value and hazard level value, and determine the high-risk path segment based on the common cause failure risk value; S5. Based on high-risk path segments, generate distributed constraints for critical cables within the same critical loop group; based on the distributed constraints, update the path cost of candidate laying paths in the 3D cable tray path diagram to generate distributed optimized paths.

[0005] In summary, due to the adoption of the above-mentioned dynamic optimization method for cable laying paths in thermal power plants based on three-dimensional models, the beneficial effects of this invention are: This invention generates critical loop groups based on cable attribute values, enabling critical cables to participate in path optimization according to their system, protected object, protection function, redundancy relationship, and safety level. This avoids the problem of existing technologies that only select paths based on cable start and end points, path length, and remaining cable tray capacity, failing to identify the protection relationships between critical cables. The invention also breaks down candidate laying paths into cable tray path segments, obtaining a path segment sequence. Based on the critical loop groups and path segment sequences, it identifies concentration values ​​within the same tray and across groups, determining the concentration status of critical cables within specific cable tray path segments. This avoids the problem of existing technologies that only determine the usability of the entire path, making it difficult to detect excessive concentration of critical cables within local cable tray path segments. This invention generates common-cause failure risk values ​​based on the concentration value and hazard level value of critical loops, and determines high-risk path segments based on these common-cause failure risk values. This allows path optimization to simultaneously consider the concentration of critical cables and the degree of danger of cable tray path segments being affected by fire, water ingress, mechanical damage, accidental contact during maintenance, and abnormal cable tray support, avoiding the concealment of common-cause failure risks in paths that are spatially accessible and have sufficient capacity. Based on high-risk path segments, it generates dispersion constraints and determines concentrated critical cables, allowable values ​​for the same group, dispersed critical cables, and candidate paths that can be dispersed, enabling the accurate identification of critical cables that need to be dispersed, avoiding indiscriminate detours of all critical cables, and reducing unnecessary path increases. This invention generates manual path verification identifiers when no alternative candidate laying paths exist, and identifies the candidate laying path with the lowest common cause failure risk value as the path to be confirmed. This avoids the direct interruption of the path optimization process when there are no alternative routes, and also avoids directly using candidate laying paths that still pass through high-risk path segments as decentralized optimization paths. Based on the decentralized constraints, the path cost of candidate laying paths is updated to generate decentralized optimization paths, so that candidate laying paths that pass through high-risk path segments are no longer preferentially selected because of their shorter path length. This reduces the common cause failure risk caused by critical protection circuits passing through the same high-risk path segment, and improves the path safety decentralized capability and reliable operation capability of key systems in thermal power plants. Attached Figure Description

[0006] Figure 1A schematic diagram of the process of the present invention is shown; Figure 2 A schematic diagram of the process for determining high-risk path segments according to the present invention is shown; Figure 3 A flowchart illustrating the distributed optimized path generation process of the present invention is shown. Detailed Implementation

[0007] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the protection scope of the present invention.

[0008] Unless otherwise defined, the technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The following detailed description, in conjunction with the accompanying drawings, illustrates the dynamic optimization method for cable laying paths in thermal power plants based on a three-dimensional model, provided by this invention. Example 1: See Figure 1 As shown, the dynamic optimization method for cable laying paths in thermal power plants based on a three-dimensional model includes: S1. The preset optimization cycle is the review cycle for cable laying design in thermal power plants, the review cycle before technical renovation construction, or the review cycle before maintenance operations. The cable attribute values ​​of critical cables are derived from the cable list, protection logic table, and panel wiring table. The candidate laying paths are derived from the three-dimensional cable tray path map. The cable attribute values ​​and candidate laying paths of critical cables are collected in each preset optimization cycle. Based on the cable system, protection object, protection function, redundancy relationship, and safety level in the cable attribute values, critical loop groups are generated. Through the above processing, each critical cable is associated with the corresponding critical loop group, so that subsequent concentrated values ​​in the same slot, concentrated values ​​across groups, and common cause failure risk values ​​can be judged based on the critical loop group. It should be noted that the methods for generating critical loop groups based on cable attribute values ​​include: Extract the cable system, protected object, protection function, redundancy relationship, and safety level of each critical cable from the cable attribute values; use the cable system, protected object, protection function, redundancy relationship, and safety level as the basis for dividing critical circuit groups. Critical cables belonging to the same system and protecting the same objects are identified as the same candidate circuit group; Within the same candidate circuit group, critical cables with the same protection function and the same redundancy relationship are identified as the same critical circuit group; When the safety levels of critical cables within the same candidate loop group are different, the safety level of the critical loop group shall be determined according to the highest safety level. Based on the safety level of the critical circuit group, critical cables within the critical circuit group are identified as circuit group identifiers.

[0009] S2. Based on the candidate laying paths, the candidate laying paths of each critical cable are divided into cable tray path segments to obtain a path segment sequence. By dividing the candidate laying paths into cable tray path segments, a path segment sequence is obtained in the order from the cable start point to the cable end point. Subsequently, the same-slot concentration value and cross-group concentration value can be statistically analyzed for the target cable tray path segment. It should be noted that, based on the candidate laying paths, the method for dividing the candidate laying path of each critical cable into cable tray path segments to obtain the path segment sequence includes: Identify the cable tray intersections, turns, wall penetrations, cable shaft entrances, cable trench entrances, and control panel access points in the 3D cable tray path diagram, and define these locations as connection nodes. Based on the continuous layable sections between adjacent connection nodes, determine the cable tray path segments. By defining the cable tray intersections, turns, wall penetrations, cable shaft entrances, cable trench entrances, and control panel access points as connection nodes, and defining the cable tray path segments based on the continuous layable sections between adjacent connection nodes, the spatial structure of the 3D cable tray path diagram forms a path segment structure that can be used for path segment statistics. The candidate laying paths of each critical cable are mapped to the connection nodes, and the connection nodes that the candidate laying paths pass through in sequence are determined. Based on the connecting nodes that the candidate laying path passes through in sequence, determine the cable tray path segment between adjacent connecting nodes. The cable tray path segments are sorted according to the order in which the candidate laying paths pass from the cable start point to the cable end point; the sorted cable tray path segments are used as the path segment sequence of the corresponding critical cables; the sorted cable tray path segments are used to represent the actual passing order of the critical cables in the three-dimensional cable tray path diagram.

[0010] S3. Based on the critical loop group and path segment sequence, identify the same-slot concentration value of critical cables within the same cable tray path segment and the cross-group concentration value of different critical loop groups to obtain the critical loop concentration value. The same-slot concentration value is used to characterize the degree of concentration of critical cables within the same critical loop group in the target cable tray path segment, and the cross-group concentration value is used to characterize the degree of concentration of different critical loop groups passing through the target cable tray path segment. Both are used as inputs to generate the critical loop concentration value. It should be noted that, based on critical loop groups and path segment sequences, methods for identifying the concentrated values ​​of critical cables within the same cable tray path segment and the concentrated values ​​across different critical loop groups to obtain critical loop concentrated values ​​include: Each cable tray path segment in the path segment sequence is sequentially identified as the target cable tray path segment; Based on the critical loop group, the number of critical cables passing through the target cable tray path segment within the same critical loop group is counted to obtain the passing value of the same group. Based on the same group pass value and the total number of critical cables in the same critical loop group, generate the same slot concentration value corresponding to the target cable tray path segment; the same slot concentration value is used to represent the correspondence between the number of critical cables passing through the target cable tray path segment in the same critical loop group and the total number of critical cables in the critical loop group. Based on the critical loop group, the number of critical loop groups passing through the target cable tray path segment is counted to obtain the cross-group passing value; Based on the cross-group traversal value and the total number of critical loop groups, the cross-group set value corresponding to the target cable tray path segment is generated; the cross-group set value is used to represent the correspondence between the number of critical loop groups traversing the target cable tray path segment and the total number of critical loop groups participating in path optimization. Based on the same-slot concentration value and cross-group concentration value, the critical loop concentration value corresponding to the target cable tray path segment is generated. The critical loop concentration value is the path segment concentration data including the same-slot concentration value and cross-group concentration value. It is used to represent the intra-group concentration state and inter-group concentration state at the target cable tray path segment level, and serves as the input for subsequent generation of common cause failure risk value.

[0011] S4. Collect the hazard level value of the cable tray path segment, generate the common cause failure risk value based on the critical loop concentration value and the hazard level value, and determine the high-risk path segment based on the common cause failure risk value; the critical loop concentration value and the hazard level value are used together as the input of the common cause failure risk value, so that the risk judgment of the target cable tray path segment is simultaneously associated with the critical cable concentration status and the hazard status of the cable tray path segment. It should be noted that the methods for collecting the hazard level values ​​of cable tray route sections include: Each cable tray path segment in the path segment sequence is identified as the target cable tray path segment. The fire compartment value, water ingress status value, mechanical damage record value, maintenance operation status value, and cable tray support status value of the target cable tray path segment are obtained. The specific values ​​of fire impact value, water ingress impact value, mechanical damage impact value, maintenance accidental contact impact value, and support abnormality impact value are provided as examples and can be preset or adjusted according to thermal power plant design specifications, historical defect records, maintenance operation records, and cable tray path segment types. The specific values ​​of subsequent preset risk thresholds, preset intra-channel concentration thresholds, preset cross-group concentration thresholds, and various path cost values ​​can also be preset or adjusted according to cable tray capacity design requirements, critical circuit safety levels, and on-site construction requirements. The fire compartment value is derived from the fire compartment map and fire sealing records; the water ingress status value is derived from the inspection records and water accumulation records; the mechanical damage record value is derived from the defect records; the maintenance operation status value is derived from the maintenance operation records and hot work operation records; and the cable tray support status value is derived from the cable tray support inspection records. The fire compartment value indicates the degree of limitation imposed by the fire compartment on the target cable tray path segment's impact on local fires and is used to determine the fire impact value. The fire impact value is a unitless value between zero and one; the larger the value, the stronger the impact of a local fire on the target cable tray path segment. When the target cable tray path segment is located in an independent fire compartment and has complete fire sealing, the fire impact value is set to 0.2; when the target cable tray path segment crosses a fire compartment and has complete fire sealing, the fire impact value is set to 0.6; when there are records of fire sealing removal or alteration on the target cable tray path segment, the fire impact value is set to 0.8; and when the target cable tray path segment crosses a fire compartment and there are records of fire sealing removal or alteration, the fire impact value is set to one. The ingress status value indicates the state of the target cable tray path segment affected by ingress or water accumulation, and is used to determine the ingress impact value. The ingress impact value is a unitless value between zero and one; the larger the value, the stronger the impact of ingress or water accumulation on the target cable tray path segment. When the target cable tray path segment has no ingress record and is not in a low-level water accumulation area, the ingress impact value is set to 0.1. When the target cable tray path segment is in a low-level water accumulation area but has no ingress record, the ingress impact value is set to 0.5. When the target cable tray path segment has an ingress or water accumulation record, the ingress impact value is set to 0.8. When the target cable tray path segment is in a low-level water accumulation area and has an ingress or water accumulation record, the ingress impact value is set to one. The mechanical damage record value indicates whether there are records of cable tray deformation, cracking, cutting, or cable sheath damage in the target cable tray path segment before the current dynamic optimization cycle, and is used to determine the mechanical damage impact value. The mechanical damage impact value is a dimensionless value between zero and one; the larger the value, the stronger the impact of mechanical damage on the target cable tray path segment. When there are no records of cable tray deformation, cracking, cutting, or cable sheath damage in the target cable tray path segment, the mechanical damage impact value is set to 0.1. When there are any records of cable tray deformation, cracking, cutting, or cable sheath damage in the target cable tray path segment, the mechanical damage impact value is set to 0.7. When there are two or more records in the target cable tray path segment, the mechanical damage impact value is set to one. The maintenance operation status value indicates whether maintenance, hot work, cable tray opening, or fireproof sealing / modification work exists on the target cable tray path segment within the current dynamic optimization cycle, and is used to determine the impact value of accidental maintenance collisions. The impact value of accidental maintenance collisions is a unitless value between zero and one; the larger the value, the stronger the impact of accidental maintenance collisions on the target cable tray path segment. When there are no maintenance, hot work, cable tray opening, or fireproof sealing / modification work on the target cable tray path segment, the impact value of accidental maintenance collisions is set to 0.1. When there are maintenance or cable tray opening work on the target cable tray path segment, the impact value of accidental maintenance collisions is set to 0.6. When there are hot work or fireproof sealing / modification work on the target cable tray path segment, the impact value of accidental maintenance collisions is set to 0.8. When there are both hot work and cable tray opening work on the target cable tray path segment, the impact value of accidental maintenance collisions is set to one. The cable tray support status value indicates whether the cable tray support of the target cable tray route segment meets the support requirements and is used to determine the support anomaly impact value. The support anomaly impact value is a unitless value between zero and one. The larger the value, the stronger the impact of the cable tray support anomaly on the target cable tray route segment. When the cable tray support of the target cable tray route segment is complete and there is no record of loosening, the support anomaly impact value is set to 0.1. When there is a record of loosening of the cable tray support in the target cable tray route segment, the support anomaly impact value is set to 0.6. When there is a record of missing cable tray support or cable tray subsidence in the target cable tray route segment, the support anomaly impact value is set to 0.8. When there are records of both missing cable tray support and cable tray subsidence in the target cable tray route segment, the support anomaly impact value is set to one. The maximum value among the fire impact value, water ingress impact value, mechanical damage impact value, maintenance accidental contact impact value, and support abnormality impact value is determined as the hazard level value of the target cable tray path segment; Through the above processing, the hazard level value is determined by the fire impact value, water ingress impact value, mechanical damage impact value, maintenance accidental contact impact value, and support abnormality impact value, and serves as the basis for determining the subsequent local accident trigger value.

[0012] It should be noted that when generating common cause failure risk values ​​based on critical loop concentration values ​​and hazard level values, the same-slot concentration values ​​and cross-group concentration values ​​are first extracted from the critical loop concentration values. The same-slot concentration values, cross-group concentration values, and hazard level values ​​are then converted into redundancy reduction values, common damage values, and local accident trigger values, respectively. Then, intra-group risk values, inter-group risk values, and common cause failure risk values ​​are generated based on the redundancy reduction values, common damage values, and local accident trigger values. Considering that when critical cables within the same critical circuit group pass through the same cable tray path segment, the redundancy and dispersion effect of the critical circuit group is weakened; when different critical circuit groups pass through the same cable tray path segment, the possibility of multiple protection functions being simultaneously damaged increases; and the cable tray path segment itself is susceptible to fire, water ingress, mechanical damage, maintenance accidental contact, and abnormal support conditions, which can affect the probability of triggering local accidents, this embodiment converts the same-slot concentration state, cross-group concentration state, and cable tray path segment danger state into risk values ​​within the same value range, and generates common-cause failure risk values ​​accordingly. In one specific embodiment, firstly, each cable tray path segment in the path segment sequence is sequentially determined as a target cable tray path segment; for any target cable tray path segment, the number of critical cables passing through the target cable tray path segment within the same critical circuit group is counted, and this number is divided by the total number of critical cables within the critical circuit group to obtain the same-slot concentration sub-value of the critical circuit group within the target cable tray path segment; when the target cable tray path segment corresponds to multiple critical circuit groups, the maximum value among the multiple same-slot concentration sub-values ​​is taken as the same-slot concentration value of the target cable tray path segment. Subsequently, the number of critical loop groups passing through the target cable tray path segment is counted, and this number is divided by the total number of critical loop groups participating in the current preset optimization cycle to obtain the cross-group concentration value of the target cable tray path segment. The fire impact value, water ingress impact value, mechanical damage impact value, maintenance accidental contact impact value, and support anomaly impact value corresponding to the target cable tray path segment are obtained, and the maximum value among these impact values ​​is taken as the hazard level value of the target cable tray path segment. Further, the concentration value within the same trench is taken as the redundancy reduction value, the cross-group concentration value as the common damage value, and the hazard level value as the local accident trigger value. The redundancy reduction value and the local accident trigger value are added together and averaged to obtain the intra-group risk value of the target cable tray path segment; the common damage value and the local accident trigger value are added together and averaged to obtain the inter-group risk value of the target cable tray path segment. The intra-group risk value and the inter-group risk value are compared, and the larger value is taken as the common cause failure risk value of the target cable tray path segment. When the risk value of common cause failure is not less than the preset risk threshold, the target cable tray path segment is determined as the path segment to be confirmed; the target cable tray path segment with a common cause failure risk value not less than the preset risk threshold is determined as the path segment to be confirmed, and the path segment to be confirmed is used as the object of subsequent secondary judgment of the same-slot centralized threshold and cross-group centralized threshold. The preset risk threshold is a unitless value used to determine whether a target cable tray path segment is a high-risk path segment. The preset risk threshold and the common cause failure risk value share the same value range, both set between zero and one. A higher value indicates a higher permissible common cause failure risk for the target cable tray path segment. The preset risk threshold is determined based on the safety level of the critical loop group, the hazard level of the target cable tray path segment, and the preset allowable concentration quantity. The preset allowable concentration quantity is a pre-configured quantity based on design specifications, the safety level of the critical loop group, and the type of cable tray path segment before the start of the current preset optimization cycle. A higher safety level of the critical loop group results in a lower preset risk threshold; a higher hazard level of the target cable tray path segment results in a lower preset risk threshold; and a smaller allowable concentration of critical cables within the same target cable tray path segment results in a lower preset risk threshold. For example, when the safety level of the critical loop group is the highest safety level and the hazard level of the target cable tray path segment is the highest hazard level, the preset risk threshold is set to 0.5; when the safety level of the critical loop group is the normal safety level and the hazard level of the target cable tray path segment is a lower safety level, the preset risk threshold is set to 0.8. When the common cause failure risk value of the target cable tray path segment is greater than or equal to the corresponding preset risk threshold, the target cable tray path segment is identified as a path segment to be confirmed; when the path segment to be confirmed meets the same-slot concentration value reaching the preset same-slot concentration threshold, or meets the cross-group concentration value reaching the preset cross-group concentration threshold, the path segment to be confirmed is identified as a high-risk path segment.

[0013] See Figure 2 It should be noted that the methods for identifying high-risk path segments based on the unconfirmed path segments include: S101. Obtain the same-slot concentration value and cross-group concentration value corresponding to the path segment to be confirmed, and determine whether the same-slot concentration value reaches the preset same-slot concentration threshold, or determine whether the cross-group concentration value reaches the preset cross-group concentration threshold; after the path segment to be confirmed is judged twice by the preset same-slot concentration threshold or the preset cross-group concentration threshold, the path segment to be confirmed that meets the conditions is determined as a high-risk path segment. S102. If the following conditions are met, i.e., the concentration value of the same slot reaches the preset concentration threshold of the same slot or the concentration value of the cross group reaches the preset concentration threshold of the cross group, then the path segment to be confirmed is identified as a high-risk path segment. If the conditions are not met, the common cause failure risk value of the path segment to be confirmed is retained and it continues to participate in the judgment of the next dynamic optimization cycle; if the path segment to be confirmed does not meet the judgment conditions of the same slot concentration value or cross group concentration value, the common cause failure risk value of the path segment to be confirmed is retained and re-judged in the next dynamic optimization cycle based on the updated critical loop concentration value and hazard level value.

[0014] Specifically, the preset co-cage concentration threshold is a unitless proportional value used to determine whether critical cables within the same critical circuit group are excessively concentrated in the target cable tray path segment. The preset co-cage concentration threshold and the co-cage concentration value use the same value range, both set between zero and one; the lower the value, the stricter the restriction on the co-cage laying of critical cables within the same critical circuit group. The preset co-cage concentration threshold is determined based on the safety level of the critical circuit group, the total number of critical cables within the critical circuit group, and the number of critical cables from the same group allowed to pass through the same cable tray path segment. The higher the safety level of the critical circuit group, the lower the preset co-cage concentration threshold; the fewer the total number of critical cables within the same critical circuit group, the lower the preset co-cage concentration threshold; the fewer the number of critical cables from the same group allowed to pass through the same cable tray path segment, the lower the preset co-cage concentration threshold. For example, when the safety level of the critical circuit group is the highest safety level, and only a small number of critical cables within the same critical circuit group are allowed to pass through the same target cable tray path segment, the preset co-cage concentration threshold is set to 0.5; when the safety level of the critical circuit group is the normal safety level, the preset co-cage concentration threshold is set to 0.7. When the same-slot concentration value corresponding to the target cable tray path segment is greater than or equal to the preset same-slot concentration threshold, it indicates that there is a risk of same-slot concentration of critical cables in the same critical circuit group within the target cable tray path segment. The preset cross-group concentration threshold is a unitless proportional value used to determine whether different critical loop groups are jointly concentrated within the target cable tray path segment. The preset cross-group concentration threshold and the cross-group concentration value share the same value range, both set between zero and one. A lower value indicates a stricter restriction on different critical loop groups sharing the same target cable tray path segment. The preset cross-group concentration threshold is determined based on the total number of critical loop groups participating in path optimization, the number of critical loop groups allowed to pass through the target cable tray path segment, and the safety level of the critical loop groups. A lower total number of critical loop groups participating in path optimization results in a lower preset cross-group concentration threshold; a lower number of critical loop groups allowed to pass through the target cable tray path segment results in a lower preset cross-group concentration threshold; and a higher safety level of the critical loop groups passing through the target cable tray path segment results in a lower preset cross-group concentration threshold. For example, when the critical loop groups involved in path optimization include the turbine protection critical loop group, the boiler protection critical loop group, and the generator-transformer protection critical loop group, and the target cable tray path segment only allows one of the critical loop groups to pass through, the preset cross-group concentration threshold is set to 0.35; when the target cable tray path segment allows two critical loop groups to pass through, the preset cross-group concentration threshold is set to 0.6; when the safety level of the critical loop group passing through the target cable tray path segment is low, the preset cross-group concentration threshold is set to 0.7. When the cross-group concentration value corresponding to the target cable tray path segment is greater than or equal to the preset cross-group concentration threshold, it indicates that there is cross-group concentration risk for different critical loop groups within that target cable tray path segment.

[0015] Through the above processing, the intra-group risk value reflects both the concentration within the same critical loop group and the degree of local accident triggering in the target cable tray path segment, while the inter-group risk value reflects both the degree to which different critical loop groups pass through the target cable tray path segment and the degree of local accident triggering in the target cable tray path segment.

[0016] S5. Based on high-risk path segments, generate distributed constraints for critical cables within the same critical loop group. The distributed constraints are generated based on high-risk path segments to determine the distributed critical cables that need to be adjusted, and to restrict the distributed critical cables from continuing to preferentially pass through high-risk path segments during subsequent path cost updates. It should be noted that, based on high-risk path segments, methods for generating distributed constraints for critical cables within the same critical loop group include: Critical cables that pass through high-risk path segments and belong to the same critical loop group are selected from the path segment sequence to obtain concentrated critical cables; concentrated critical cables are used for subsequent judgment of allowable values ​​in the same group. Based on the safety level of the critical loop group, the allowable value of the same group corresponding to the high-risk path segment is determined, and the number of concentrated critical cables is compared with the allowable value of the same group; the allowable value of the same group is used to limit the number of critical cables that can be retained in the high-risk path segment of the same critical loop group. When the number of concentrated critical cables exceeds the allowable value for the same group, the common cause failure risk value corresponding to the high-risk path segment traversed by each concentrated critical cable is obtained. When the same concentrated critical cable traverses multiple high-risk path segments, the largest common cause failure risk value is determined as the concentrated cable risk value for that concentrated critical cable. Concentrated critical cables are sorted from high to low according to their concentrated cable risk values. When concentrated cable risk values ​​are the same, concentrated critical cables with available divisible candidate laying paths are prioritized. If they are still the same, concentrated critical cables with a smaller increase in path cost are prioritized; where the increase in path cost is the difference between the original path cost of the divisible candidate laying path and the original path cost of the current candidate laying path for the concentrated critical cable. Concentrated critical cables exceeding the allowable value for the same group after sorting are identified as divisible critical cables, and these divisible critical cables are used as the objects for subsequent re-sorting of candidate laying paths. Based on the candidate laying paths of distributed critical cables, candidate laying paths that do not pass through high-risk path segments and meet the requirements of cable start-to-end connectivity, cable tray remaining capacity, and construction accessibility are selected to obtain the distributed candidate laying paths. These distributed candidate laying paths are used as alternative paths for distributed critical cables to avoid high-risk path segments. If there are decentralizable candidate laying paths, it indicates that there is a complete alternative path for the decentralized critical cable that can avoid the high-risk path segment. Decentralization constraints are generated based on the decentralized critical cable, the high-risk path segment, and the decentralizable candidate laying paths. The decentralization constraints are used to increase the path cost value of candidate laying paths that pass through the high-risk path segment when updating the path cost, and retain the decentralizable candidate laying paths in the candidate laying path ranking. If no alternative laying path exists, it indicates that there is no alternative path in the current 3D cable tray path map that simultaneously meets the connectivity requirements, cable tray remaining capacity requirements, and construction accessibility requirements for the distributed critical cable. In this case, a path manual review mark is generated, and the candidate laying path with the lowest path risk value is selected from the candidate laying paths corresponding to the distributed critical cable as the path to be confirmed. The path to be confirmed is submitted to the designer for review and is not directly output as the distributed optimization path. When a candidate laying path includes multiple cable tray path segments, the common cause failure risk value corresponding to each cable tray path segment in the candidate laying path is obtained, and the largest common cause failure risk value is determined as the path risk value of the candidate laying path; when multiple candidate laying paths have the same path risk value, the candidate laying path with the smaller original path cost is selected as the path to be confirmed.

[0017] To further clarify, the methods for determining the permissible values ​​for the same group based on the safety level of the critical loop group include: Obtain the safety level of the critical circuit group to which the centralized critical cable belongs; Based on the safety level, determine the number of critical cables that can be retained in the high-risk path segment of the critical loop group; When the security level is the highest security level, the allowable value for the same group is set as the preset first number of roots; When the security level is lower than the highest security level but higher than the normal security level, the allowable value for the same group will be set as the preset second number of roots; When the security level is normal, the allowable value in the same group is set as the preset third root number; The permissible value for the same group corresponds to a preset first, second, or third number of wires, depending on the safety level of the critical loop group. Through the above processing, different permissible values ​​for the same group are assigned to critical loop groups with different safety levels.

[0018] Specifically, the preset first number is the number of critical cables allowed to be retained in a high-risk path segment for the highest safety level critical circuit group. This is used to impose the strictest concentration restrictions on the highest safety level critical cables within the same group. The preset first number is determined based on the protection importance of the highest safety level critical circuit group, the common cause failure risk value of the high-risk path segment, and the total number of critical cables within the same critical circuit group. When the highest safety level critical circuit group passes through a high-risk path segment, the preset first number is set to one, ensuring that only one critical cable within the same critical circuit group passes through that high-risk path segment, and the remaining concentrated critical cables are identified as dispersed critical cables. The preset second number is the number of critical cables that a critical loop group with a safety level lower than the highest safety level but higher than the ordinary safety level is allowed to retain in a high-risk path segment. The preset second number is determined based on the safety level of the critical loop group, the number of concentrated critical cables, and the hazard level of the high-risk path segment. When the critical loop group passes through a high-risk path segment, the preset second number is set to two, so that a maximum of two critical cables are retained in the same critical loop group through the high-risk path segment. Concentrated critical cables exceeding two are identified as distributed critical cables. The preset third number represents the number of critical cables that a critical circuit group of ordinary safety level is allowed to retain within a high-risk path segment. The preset third number is determined based on the protection importance of the critical circuit group of ordinary safety level, the number of centralized critical cables, and the availability of decentralized candidate laying paths. When a critical circuit group of ordinary safety level passes through a high-risk path segment, the preset third number is set to three, ensuring that a maximum of three critical cables from the same critical circuit group are retained through that high-risk path segment. Concentrated critical cables exceeding three are identified as decentralized critical cables.

[0019] Based on the distributed constraints, the path cost of candidate laying paths in the three-dimensional cable tray path map is updated to generate distributed optimized paths. Based on the distributed constraints, the path cost of candidate laying paths is updated, and the common cause failure risk value and high-risk path segments are used as the sorting criteria for candidate laying paths.

[0020] See Figure 3 It should be noted that, based on the distributed constraints, the method for updating the path cost of candidate laying paths in the 3D cable tray path diagram and generating distributed optimized paths includes: S201. Based on the distributed constraints, determine the candidate laying path corresponding to each distributed critical cable; S202. When a candidate laying path passes through a high-risk path segment, a risk cost value is generated based on the common cause failure risk value corresponding to the high-risk path segment. The risk cost value is generated based on the common cause failure risk value corresponding to the high-risk path segment. The higher the common cause failure risk value, the greater the corresponding risk cost value. The risk excess value is the difference between the common cause failure risk value corresponding to the high-risk path segment and a preset risk threshold; when the difference is less than zero, the risk excess value is set to zero. The risk cost value is the product of the risk excess value and a preset risk amplification coefficient. The preset risk amplification coefficient is determined based on the range of the original path cost value, so that the candidate laying paths passing through high-risk path segments can reflect the impact of common cause failure risk when sorting. S203. Add the risk value to the original path value of the candidate laying path to obtain the updated path value; after adding the risk value to the original path value of the candidate laying path, the updated path value is used for subsequent candidate laying path ranking. The original path cost value is the basic laying cost of the candidate laying path before the risk cost value is added, and the original path cost value is a unitless value. The method for generating the original path cost value includes obtaining the path length, remaining cable tray capacity, number of turns, and construction accessibility of the candidate laying path corresponding to each dispersed critical cable; generating the length cost value based on the path length; generating the capacity cost value based on the remaining cable tray capacity; generating the turn cost value based on the number of turns; generating the accessibility cost value based on the construction accessibility; and generating the original path cost value based on the length cost value, capacity cost value, turn cost value, and accessibility cost value. S204. When a candidate laying path is a divisible candidate laying path and does not pass through high-risk path segments, the original path cost of the candidate laying path remains unchanged; when a candidate laying path does not pass through high-risk path segments and meets the divisibility constraint condition, the original path cost is used as the current path cost of the candidate laying path. S205. Based on the updated path value and the original path value, determine the current path value of each candidate laying path; based on the current path value, sort the candidate laying paths corresponding to each dispersed critical cable. When there is a cable tray path segment in the candidate laying path whose remaining capacity is less than the capacity required for laying the new critical cable, or when the cable tray path segment through which the candidate laying path passes does not have the conditions for construction entry within the current dynamic optimization cycle, the candidate laying path is marked as a path that cannot be directly output. S206. The candidate laying path with the lowest current path cost, meeting the dispersion constraints, and not marked as a path that cannot be directly output is determined as the dispersion optimization path for the corresponding dispersion critical cable. After generating the dispersion optimization path, the critical cable number, critical loop group, high-risk path segment, common cause failure risk value, current path cost, and dispersion optimization path are written into the cable laying design record; if a path manual review mark is generated, the path to be confirmed is submitted to the designer for review.

[0021] Specifically, the length cost value represents the impact of the candidate laying path length on the laying cost. The length cost value is a dimensionless value between zero and one; the longer the candidate laying path, the greater the length cost value. The shortest path length among all candidate laying paths corresponding to the same distributed critical cable is used as the baseline length. When the path length of the candidate laying path is no greater than 1.2 times the baseline length, the length cost value is set to 0.2; when the path length of the candidate laying path is greater than 1.2 times but no greater than 1.5 times the baseline length, the length cost value is set to 0.5; and when the path length of the candidate laying path is greater than 1.5 times the baseline length, the length cost value is set to 0.8. The length cost value is used in the generation of the original path cost value. The capacity cost value represents the impact of the remaining cable tray capacity of the cable tray segments traversed by the candidate laying path on the laying cost. The capacity cost value is a dimensionless value between zero and one; the smaller the remaining cable tray capacity, the larger the capacity cost value. Specifically, when all cable tray segments traversed by the candidate laying path meet the capacity required for laying the new critical cable, the capacity cost value is set to 0.2; when the remaining cable tray capacity of a segment in the candidate laying path is close to the capacity required for laying the new critical cable, the capacity cost value is set to 0.6; when the remaining cable tray capacity of a segment in the candidate laying path is less than the capacity required for laying the new critical cable, the capacity cost value is set to one, and the candidate laying path is marked as a path that cannot be directly output. Paths that cannot be directly output are not output as distributed optimization paths; when there are no other candidate laying paths that meet the capacity and construction accessibility requirements, the path that cannot be directly output is submitted to the designer for review as a path to be confirmed. The capacity cost value is used in the generation of the original path cost value and is used to record the basic laying cost of the candidate laying path. The turning cost value represents the impact of the number of turns in a candidate laying path on the laying cost. The turning cost value is a dimensionless value between zero and one; the more turns, the greater the turning cost value. Specifically, when the number of turns in a candidate laying path is no more than two, the turning cost value is set to 0.2; when the number of turns in a candidate laying path is more than two but no more than five, the turning cost value is set to 0.5; and when the number of turns in a candidate laying path is more than five, the turning cost value is set to 0.8. The turning cost value is used in the generation of the original path cost value. The reachability cost value represents the impact of candidate laying paths on construction accessibility. The reachability cost value is a dimensionless value between zero and one; the worse the construction accessibility, the higher the reachability cost value. Specifically, when the cable tray route through which the candidate laying path passes has a conventional construction access, the reachability cost value is set to 0.2; when the cable tray route through which the candidate laying path passes requires a temporary platform or partial disassembly before construction, the reachability cost value is set to 0.6; when the cable tray route through which the candidate laying path passes does not have construction access conditions within the current dynamic optimization cycle, the reachability cost value is set to one, and the candidate laying path is marked as a path that cannot be directly output. Paths that cannot be directly output are not output as distributed optimization paths. When there are no other candidate laying paths that meet the capacity and construction accessibility requirements, the path that cannot be directly output is submitted to the designer for review as a path to be confirmed. The reachability cost value is used in the generation of the original path cost value and to record the construction accessibility status of candidate laying paths. Among them, the capacity cost and the accessibility cost are used to record the basic laying cost of candidate laying paths and are used for designer review. If a candidate laying path is marked as a path that cannot be directly output, then even if the candidate laying path has the current path cost, it will not participate in the direct output of the decentralized optimization path. It will only be submitted to the designer for review as a path to be confirmed when there are no other candidate laying paths that meet the capacity requirements and construction accessibility requirements. When generating the original path cost based on the cost per unit length, capacity, turning radius, and accessibility, these costs are added together to obtain the original path cost. Since the cost per unit length, capacity, turning radius, and accessibility are all dimensionless values ​​with a consistent range, the summed original path cost remains dimensionless. A higher original path cost indicates a higher basic laying cost for the candidate laying path in terms of path length, remaining cable tray capacity, number of turns, and construction accessibility.

[0022] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the dynamic optimization method for cable laying path of thermal power plants based on three-dimensional models and the inventive concept, should be covered within the scope of protection of the present invention.

Claims

1. A dynamic optimization method for cable laying paths in thermal power plants based on a three-dimensional model, characterized in that, Includes the following steps: Collect the cable attribute values ​​and candidate laying paths of key cables within each preset optimization cycle, and generate key loop groups based on the cable attribute values; Based on the candidate laying paths, the candidate laying paths of each critical cable are divided into cable tray path segments to obtain a path segment sequence. Based on the critical loop group and path segment sequence, the concentrated value of critical cables in the same tray and the concentrated value across different critical loop groups within the same cable tray path segment are identified to obtain the concentrated value of critical loops. Collect the hazard level values ​​of the cable tray route segments, generate common cause failure risk values ​​based on the critical loop concentration values ​​and hazard level values, and determine high-risk route segments based on the common cause failure risk values; Based on high-risk path segments, generate distributed constraints for critical cables within the same critical loop group. Based on the distributed constraints, the path cost of candidate laying paths in the 3D cable tray path graph is updated to generate distributed optimized paths.

2. The method for dynamic optimization of cable laying paths in thermal power plants based on a three-dimensional model according to claim 1, characterized in that, Methods for generating common-cause failure risk values ​​based on critical loop lumped values ​​and hazard level values, and for determining high-risk path segments based on these common-cause failure risk values, include: Extract the same-slot concentrated value and cross-group concentrated value from the concentrated values ​​of the critical loop; Based on the concentrated values ​​in the same slot, determine the redundancy reduction value of the same critical loop group in the target cable tray path segment; Based on the cross-group concentrated values, the common damage values ​​of different critical loop groups within the target cable tray path segment are determined; Based on the hazard level value, determine the local accident trigger value for the target cable tray path segment; Based on redundancy reduction value, common damage value and local accident trigger value, the intra-group risk value and inter-group risk value of the target cable tray path segment are determined respectively, and the common cause failure risk value is generated based on the intra-group risk value and inter-group risk value. When the risk value of common cause failure is not less than the preset risk threshold, the target cable tray path segment is determined as the path segment to be confirmed. Based on the unconfirmed path segments, high-risk path segments are identified.

3. The method for dynamic optimization of cable laying paths in thermal power plants based on a three-dimensional model according to claim 2, characterized in that, Methods for identifying high-risk path segments based on unconfirmed path segments include: Obtain the same-slot concentration value and cross-group concentration value corresponding to the path segment to be confirmed, and determine whether the same-slot concentration value reaches the preset same-slot concentration threshold, or determine whether the cross-group concentration value reaches the preset cross-group concentration threshold. If the concentration value within the same slot reaches the preset concentration threshold within the same slot, or the concentration value across groups reaches the preset concentration threshold across groups, then the path segment to be confirmed will be identified as a high-risk path segment.

4. The method for dynamic optimization of cable laying paths in thermal power plants based on a three-dimensional model according to claim 2, characterized in that, Methods for generating common cause failure risk values ​​include: Based on redundancy reduction values ​​and local accident trigger values, generate intra-group risk values ​​for the same critical loop group; Based on common damage values ​​and local accident trigger values, generate inter-group risk values ​​for different critical loop groups; Compare within-group risk values ​​and between-group risk values; When the risk value within a group is not less than the risk value between groups, the risk value within the group is taken as the common cause failure risk value of the target cable tray path segment. When the inter-group risk value is greater than the intra-group risk value, the inter-group risk value is taken as the common cause failure risk value of the target cable tray path segment.

5. The method for dynamic optimization of cable laying paths in thermal power plants based on a three-dimensional model according to claim 1, characterized in that, Methods for generating critical loop groups based on cable attribute values ​​include: Extract the cable system, protected object, protection function, redundancy relationship and safety level of each critical cable from the cable attribute values; Critical cables belonging to the same system and protecting the same objects are identified as the same candidate circuit group; Within the same candidate circuit group, critical cables with the same protection function and the same redundancy relationship are identified as the same critical circuit group.

6. The method for dynamic optimization of cable laying paths in thermal power plants based on a three-dimensional model according to claim 1, characterized in that, Methods for obtaining a path segment sequence include: Extract connection nodes and cable tray path segments from the 3D cable tray path diagram; The candidate laying paths are mapped to the connecting nodes, and the connecting nodes that the candidate laying paths pass through in sequence are determined. Based on the connecting nodes that the candidate laying path passes through in sequence, determine the cable tray path segment between adjacent connecting nodes. The cable tray path segments are sorted according to the order in which the candidate laying paths pass from the cable start point to the cable end point; The sorted cable tray path segments are used as the path segment sequence for the corresponding critical cables.

7. The method for dynamic optimization of cable laying paths in thermal power plants based on a three-dimensional model according to claim 1, characterized in that, Methods for obtaining the lumped values ​​of the critical loop include: Each cable tray path segment in the path segment sequence is sequentially identified as the target cable tray path segment; Count the number of critical cables passing through the target cable tray path segment within the same critical loop group to obtain the passing value for the same group; Based on the pass value of the same group and the total number of critical cables in the same critical loop group, generate the concentrated value of the same slot; The number of critical loop groups passing through the target cable tray path segment is counted to obtain the cross-group traversal value; Based on the cross-group transit value and the total number of critical loop groups, generate the cross-group concentrated value corresponding to the target cable tray path segment; Based on the concentrated values ​​within the same slot and the concentrated values ​​across groups, the concentrated values ​​of the critical loops corresponding to the target cable tray path segment are generated.

8. The method for dynamic optimization of cable laying paths in thermal power plants based on a three-dimensional model according to claim 1, characterized in that, Methods for generating distributed constraints include: Critical cables that pass through high-risk path segments and belong to the same critical loop group are selected from the path segment sequence to obtain concentrated critical cables; Based on the safety level of the critical circuit group, determine the allowable value for the same group, and compare the number of centralized critical cables with the allowable value for the same group. When the number of centralized critical cables exceeds the allowable value for the same group, the centralized critical cables exceeding the allowable value for the same group are identified as decentralized critical cables. Based on the candidate laying paths of the distributed critical cables, the dispersible candidate laying paths are screened out. If there are candidate laying paths that can be dispersed, then dispersed constraints are generated based on the dispersed critical cables, high-risk path segments, and candidate laying paths that can be dispersed.

9. The method for dynamic optimization of cable laying paths in thermal power plants based on a three-dimensional model according to claim 8, characterized in that, Methods for determining permissible values ​​for the same group based on the safety level of the critical loop group include: Obtain the safety level of the critical circuit group to which the centralized critical cable belongs; Based on the safety level, determine the number of critical cables that can be retained in the high-risk path segment of the critical loop group; When the security level is the highest security level, the allowable value for the same group is set as the preset first number of roots; When the security level is lower than the highest security level but higher than the normal security level, the allowable value for the same group will be set as the preset second number of roots; When the security level is normal, the allowable value in the same group is set as the preset third root number; Among them, the first preset number of roots is less than the second preset number of roots, and the second preset number of roots is less than or equal to the third preset number of roots.

10. The method for dynamic optimization of cable laying paths in thermal power plants based on a three-dimensional model according to claim 8, characterized in that, Methods for generating distributed optimization paths include: Based on the distributed constraints, candidate laying paths for distributed critical cables are determined. When a candidate laying path passes through a high-risk path segment, a risk cost value is generated based on the common cause failure risk value corresponding to the high-risk path segment. The risk value is added to the original path value of the candidate laying path to obtain the updated path value. When the candidate laying path is a dispersible candidate laying path and does not pass through high-risk path segments, the original path value of the candidate laying path remains unchanged. Based on the updated path value and the original path value, the current path value of the candidate laying paths is determined; based on the current path value, the candidate laying paths corresponding to the distributed critical cables are sorted. The candidate laying path that has the lowest current path cost, meets the dispersion constraint conditions, and is not marked as a path that cannot be directly output is determined as the dispersion optimization path for the corresponding dispersion critical cable.

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