Offshore booster station distributed fresh air intelligent control method

Abstract

The present application relates to the field of offshore booster station fresh air adaptive control, in particular to a kind of offshore booster station distributed fresh air intelligent control method.The method sets regional node according to cabin and branch, forms fresh air demand state quantity with security level and reliability according to air quality, heat and humidity state, salt fog risk, cabin pressure difference, execution state and equipment load, and is converted into candidate air volume;Regional node exchanges demand difference, transferable air volume and execution capacity according to air path coupling relationship, iteratively corrects candidate air volume, public fresh air unit node adjusts total supply air capacity, and station-level coordination node verifies collaborative results with hierarchical safety boundary.The limited replacement quantity is formed by using correlation verification sequence when measuring anomaly, and local degradation is executed and supply distribution of the rest of the region is rebuilt when communication or node is abnormal.The present application shortens the decision chain from environmental change to fresh air execution, maintains public air volume balance and key cabin protection boundary, and limits the influence of single-point anomaly on continuous adjustment of other regions.

Description

Technical Field

[0001] This invention relates to the field of adaptive control of fresh air in offshore substations, specifically a distributed intelligent control method for fresh air in offshore substations. Background Technology

[0002] Offshore substations are far from land and operate in a marine environment characterized by high humidity, high salt spray, and rapidly changing wind conditions. The substations also house high-voltage power distribution rooms, relay protection rooms, communication equipment rooms, battery rooms, transformer auxiliary equipment areas, and personnel activity areas. Different compartments have varying requirements for temperature, humidity, cleanliness, gas concentration, and positive / negative pressure relationships. Existing fresh air systems are typically centrally managed by HVAC control cabinets or station-level monitoring platforms. Operating hours are set according to season, shift schedules, and designed air changes per hour. During permitted periods, inlet valves, filters, supply fans, and exhaust fans are opened sequentially, maintaining total airflow at fixed frequencies, valve positions, or preset duct static pressure. The inlet side utilizes rainproof louvers, coarse filters, and salt spray filters to limit the entry of marine aerosols, and locally incorporates heating or dehumidification components to handle high-humidity air. The control cabinet receives signals for fires, target gases, and equipment malfunctions, and closes relevant valves or stops supply and exhaust air when safety interlocks are triggered. Operators adjust the set values ​​based on filter pressure differential, environmental records, and inspection results to ensure that each compartment receives basic ventilation under a unified operating strategy.

[0003] To adapt to changes in cabin load, more complex existing solutions deploy temperature, humidity, particulate matter, gas concentration, and differential pressure sensors in each area. Independent feedback loops are used to adjust the opening of terminal air valves or the speed of zone fans, and the common fresh air unit adjusts the air supply capacity based on maximum area demand, duct static pressure, or the sum of terminal valve positions. Some station-level platforms also aggregate electrical equipment loads and outdoor weather data, estimating the heat and humidity load for the next period based on historical trends, and then uniformly distributing airflow targets to each area. While this type of control can reflect some local changes, each zone loop is typically tuned separately, with zones only indirectly connected through common duct pressure. When multiple cabins simultaneously request increased airflow, station-level nodes need to collect all status data, perform unified calculations, and distribute the targets level by level. Zone controllers continue to execute the old targets while waiting for updates. If abnormalities occur in valve feedback, branch differential pressure, or environmental measurements, existing controls often use fixed substitute values ​​or global alarms, making it difficult to continue coordinating airflow using available information from adjacent branches.

[0004] Therefore, when facing the heterogeneous environmental demands of multiple compartments and the coupled operation of public fresh air units and airflow capacity, the main obstacle of existing solutions lies in the fact that local environmental changes cannot immediately generate airflow requests that can be compared and negotiated with other compartments within the region. Instead, they must rely on centralized nodes to aggregate and then uniformly allocate airflow. Centralized calculations consolidate air quality, heat and humidity load, salt spray intrusion risk, differential pressure protection, and execution margins into a single decision chain. Any data delay, link interruption, or unavailability of a station-level node will cause cross-compartment targets to stop updating. If each area increases its airflow independently, it may cause public unit capacity to exceed limits, branch differential pressure to disturb each other, or the protection boundaries of critical compartments to be squeezed out by low-priority demands. This creates a control contradiction that runs through normal and abnormal operation. Existing fresh air control cannot maintain the overall station safety boundary and public airflow balance while allowing each compartment to respond autonomously based on its local state and continuously coordinate through limited adjacency information. This results in a long decision chain and single-point dependence between environmental risk changes and executable airflow. Summary of the Invention

[0005] The purpose of this invention is to provide a distributed intelligent control method for fresh air in offshore substations, which can solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A distributed fresh air intelligent control method for an offshore substation includes: configuring regional control nodes according to the cabin and its fresh air branch; collecting cabin environmental status, branch execution status and associated electrical equipment load by each regional control node to form a fresh air demand status quantity with safety level and allowable adjustment range; and converting the fresh air demand status quantity into candidate air volume for the area. Establish node adjacency relationships based on the air path coupling relationship between fresh air branches, and control nodes in adjacent areas exchange demand differences, transferable air volume and execution capacity, and iteratively correct candidate air volume; The public fresh air unit node adjusts the total air supply capacity according to the corrected candidate air volume of each area, and the station-level coordination node issues the safety boundary and verifies the air volume results of each area control node; When the area control node or node communication is abnormal, the abnormal area performs local degradation control based on the nearest trusted boundary, and the remaining areas redetermine the transferable air volume based on the abnormality identifier.

[0007] Preferably, each area control node forms an air quality status, a heat and humidity status, a salt spray intrusion status, a cabin pressure difference status, and an execution availability status, and encodes the measurement reliability and change trend corresponding to each status as a status label; The state components participating in this control are selected according to the safety level order issued by the station-level coordination node. The deviation of the state components from their respective allowable intervals is mapped to the common demand domain. The maximum safety deviation and cumulative environmental deviation in the common demand domain are combined into the fresh air demand state quantity. The fresh air demand state quantity is also bound to the sampling time, cabin identifier and branch identifier.

[0008] Preferably, a directional airflow path map is constructed based on the upstream and downstream connections of the public air duct, the service range of the supply and exhaust air equipment, and the coupling direction of the chamber pressure difference. The regional control node is mapped to the demand node in the directional airflow path map, and the public fresh air unit node is mapped to the supply node. Adjacency is established only when two demand nodes share a supply path or when a pressure difference transmission edge exists. The adjacency message includes the demand difference filtered by the status flag, the candidate air volume that can be reduced within the safety boundary, and the remaining execution range of the air valve and fan. The effective range of the adjacency message is constrained by the air path map version identifier.

[0009] Preferably, the station-level coordination node forms a hierarchical safety boundary based on the fire interlock status, target gas safety status, outdoor salt spray risk, protection level of critical electrical compartments, capacity and allowable power of public fresh air units, and configures a coverage relationship for each layer of safety boundary; After each regional control node completes the candidate air volume correction, it submits a result summary containing the demand status version, the adjacency message version, and the execution status version. The station-level coordination node projects the result summary to the corresponding safety boundary according to the coverage relationship, returns the boundary type and allowed correction direction to the out-of-bounds area, and generates the same round execution identifier for the result summary that passes the verification.

[0010] Preferably, each area control node configures a master measurement sequence and an associated verification sequence for the same environmental state, and generates measurement reliability based on the consistency of the change direction of the two sequences within the sliding sampling window, the sampling continuity, and the physical correlation. When the master measurement sequence is inconsistent with the associated verification sequence, the corresponding state flag is set to pending confirmation, and the change direction of the most recent reliable state is used to form a restricted substitution quantity with the current associated verification sequence; For state components with different sampling periods, maintain or interpolate according to the common sampling time, so that each state component in the fresh air demand state quantity has the same time base and confidence version.

[0011] Preferably, each area control node forms a branch transmission record based on the correspondence between the feedback of the air valve opening and the change of the branch pressure difference, and binds the branch transmission record to the corresponding transmission edge in the directed wind path diagram; When the branch pressure difference changes in the direction of the damper action are inconsistent with the direction of the transmission edge, or when the air volume balance residual in the shared supply path increases continuously, the corresponding transmission edge is marked as a restricted edge. The area control node connected along the restricted edge stops exchanging the transferable air volume, only exchanging the demand difference and the remaining execution interval, and triggering the public fresh air unit node to republish the available supply interval.

[0012] Preferably, each regional control node forms an adjacency allocation table based on the demand difference of its own region and the transferable air volume of each adjacent region, and determines the adjacency allocation order according to the safety level, wind path transmission loss and message freshness. The regional control node confirms the transfer volume under the condition that the candidate air volume in the region is not lower than the safety lower limit, deducts the confirmed transfer volume from the transferable air volume in the region and sends it to the corresponding adjacent region with a round identifier attached. The receiving node only merges confirmations with the same wind path map version and consecutive rounds, discards confirmations from duplicate rounds or with inconsistent versions, and submits a balance record of candidate air volume and confirmation volume for the current round to the public fresh air unit node.

[0013] Preferably, the layered safety boundaries are established in the following order: fire protection and target gas interlock boundary, critical electrical compartment pressure difference boundary, salt spray and hot and humid environment boundary, and equipment capacity and power boundary; When the station-level coordination node verifies the result summary, it first projects the candidate air volume to the highest priority valid boundary in the coverage chain, and then uses the projection result as the input of the next layer boundary, until all valid boundaries are projected. Each projection retains the modified area identifier, modification direction, and trigger boundary. The area control node updates the air valve or fan target based on the last layer projection result according to the execution identifier of the same round.

[0014] Preferably, the measurement confidence is stored according to the data source identifier, including the continuity component, the direction consistency component, and the physical association component. When generating the restricted substitution quantity, the regional control node first selects the verification quantity that has a definite transmission relationship with the state to be confirmed from the associated verification sequence, and then aligns the verification quantity to the common sampling time according to the historical delay corresponding to the transmission relationship. When there is more than one available verification quantity, a combined verification quantity is formed according to the credibility and stability of the transmission relationship of each verification quantity. The combined verification quantity is then trimmed according to the most recent credible state allowable interval. The trimmed record and the state flag of the unconfirmed state are written together into the fresh air demand state quantity version.

[0015] Preferably, the area control node stores the execution identifier and corresponding candidate air volume that have recently passed the security boundary verification of each layer. When the node communication is interrupted, the result summary is not verified continuously, or the reliability of the measurement in this area is lower than the usable condition, the most recent reliable candidate air volume, the minimum air volume determined by the local security level, or the interlocking air volume is selected as the downgrade target according to the anomaly type. An abnormal region publishes a non-transferable identifier and its local supply occupancy to adjacent regions that can still communicate. The adjacent regions then reconstruct their adjacency allocation tables after deducting the supply occupancy from the available supply range. After communication is restored, the abnormal region re-enters the security boundary projection with the current state version, without directly using the adjacency acknowledgments from the interruption period.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. By configuring area control nodes in each compartment and fresh air branch, and mapping air quality, thermal humidity, salt spray intrusion, differential pressure, and operational availability to fresh air demand parameters with safety levels and allowable adjustment ranges, local environmental changes can be directly converted into candidate air volumes within the area, without waiting for the station-level nodes to complete full aggregation. Area control nodes only exchange demand differences, transferable air volumes, and remaining operational ranges with adjacent nodes sharing supply paths or having differential pressure transmission relationships. Air volume transfer is then confirmed based on safety levels, airflow transmission losses, and information freshness, ensuring that public air volume flows from areas with greater supply margins to areas with more urgent demand within the actual coupling range. Public fresh air units adjust the total air supply capacity based on the corrected candidate air volumes. Station-level coordination nodes project control results layer by layer through hierarchical safety boundaries, thus ensuring that regional autonomy does not exceed constraints related to fire protection, target gases, differential pressure in critical electrical compartments, salt spray environment, and equipment capacity. Local rapid response, adjacent supply and demand balance and station-level boundary verification form a continuous link, which can shorten the decision path between risk changes and the action of air valves or fans, and limit the capacity overrun and branch disturbance caused by simultaneous air increase in multiple areas.

[0017] 2. By setting master measurement sequences and associated verification sequences for environmental states, and forming measurement reliability based on the consistency of change direction, sampling continuity, and physical correlation, sensor anomalies no longer directly translate into unverified airflow actions. Area control nodes can use associated verification quantities aligned with historical time delays and allowing interval pruning to constitute restricted substitute quantities, ensuring that a source and time-based demand state is maintained during asynchronous sampling, short-term data loss, or single measurement drift. Branch transmission records also bind valve feedback and differential pressure changes to transmission edges in the airflow diagram. When the actual response direction is inconsistent or the airflow balance residual increases, the relevant edges are restricted from transfer, preventing erroneous airflow relationships from continuing to propagate adjustment quantities. In the event of communication interruption, lack of boundary verification of results, or insufficient measurement reliability in the area, the abnormal area adopts the most recently reliable airflow, local minimum airflow, or interlocking airflow according to the anomaly type, and publishes the supply occupancy to communicable neighboring areas; the remaining areas are redistributed after deducting occupancy. Therefore, anomalies in a single node, link, or measurement source only reduce the coordination range of the affected area, while other compartments can still maintain fresh air coordination within the updated supply range. After recovery, they can re-enter the boundary verification in the current state, reducing abrupt changes caused by outdated confirmations. Attached Figure Description

[0018] Figure 1 This is a flowchart of the distributed fresh air collaborative control process. Figure 2 Output sequence of fresh air demand status variables and operation threshold graph; Figure 3 Iterative output of candidate air volume sequences and feasible boundary maps; Figure 4 This is a flowchart for abnormal degradation and recovery re-entry. Detailed Implementation

[0019] Please refer to Figure 1In one embodiment, a distributed intelligent fresh air control method for an offshore substation includes configuring regional control nodes according to the cabin and its fresh air branches. Each regional control node collects the cabin environmental status, branch execution status, and associated electrical equipment load to form a fresh air demand status quantity with safety level and allowable adjustment range, and converts the fresh air demand status quantity into candidate air volume for the region. Based on the air path coupling relationship between fresh air branches, node adjacency relationships are established. Adjacent regional control nodes exchange demand differences, transferable air volume, and execution capacity, and iteratively correct candidate air volumes. The method also includes controlling the public fresh air supply. The unit nodes adjust the total air supply capacity based on the corrected candidate air volume for each area. The station-level coordination node issues safety boundaries and verifies the air volume results of each area control node. When an area control node or node communication is abnormal, the abnormal area performs local degradation control based on the nearest trusted boundary. The remaining areas re-determine the transferable air volume based on the abnormality identifier. In implementation, the high-voltage power distribution room, relay protection room, communication equipment room, battery room, and public equipment area are regarded as control areas that can be independently collected, calculated, and executed. The public air supply section and exhaust section are used as the physical boundaries of the exchange supply margin of each area.

[0020] Specifically, each area control node stores the area identifier, supply air branch identifier, exhaust air branch identifier, service compartment type, and coupling relationship with other branches. The area identifier is used to bind environmental measurement and control results, the branch identifier is used to bind the valve position, branch pressure difference, and supply air equipment feedback, and the compartment type is used to select the environmental state and safety level that need to participate in the demand calculation. The public fresh air unit node stores the available supply air capacity, current total supply air volume, filter section operating status, and feedback summary of each branch. The station-level coordination node stores fire interlocks, target gas interlocks, critical compartment protection sequence, outdoor salt spray risk, equipment capacity, and allowable power boundaries. Area control nodes do not exchange original continuous measurement sequences, but instead exchange demand differences, supply occupancy, and execution margins after credibility screening, so that the data range of adjacent communication is consistent with the information required for air volume coordination.

[0021] In this embodiment, the cabin environment status includes temperature, humidity, particulate matter, target gas, and indoor-outdoor pressure difference. The branch execution status includes valve commands, valve feedback, branch pressure difference, supply fan operation feedback, exhaust fan operation feedback, and filter section resistance trend. The associated electrical equipment load is converted from the operating status of transformer auxiliary equipment, switchgear, protection modules, or communication equipment in the service cabin into a heat load level. The area control node establishes a data source identifier and sampling time for each type of input, first checks the dimensions, allowed direction of change, and continuity, and then writes the inputs that pass the check into the current status frame. Inputs that fail the check do not directly participate in the current air volume calculation, but retain the anomaly type, the most recent reliable value, and the associated quantity that can be used for cross-validation. Subsequently, the measurement reliability processing logic determines whether to form a restricted substitution quantity.

[0022] Preferably, each area control node establishes air quality status, heat and humidity status, salt spray intrusion status, cabin pressure difference status, and execution availability status, respectively. The measurement reliability and change trend corresponding to each status are encoded as status labels. The status components participating in this control are selected according to the safety level order issued by the station-level coordination node. The deviation of the status components from their respective allowable intervals is mapped to the common demand domain. The maximum safety deviation and cumulative environmental deviation in the common demand domain are combined into a fresh air demand status quantity. The fresh air demand status quantity is also bound to the sampling time, cabin identifier, and branch identifier. The status labels adopt mutually exclusive states of normal, pending confirmation, restricted substitution, interlock, and unavailable. The interlock state directly enters the highest safety level, the unavailable state is excluded from the cumulative environmental deviation calculation, and the pending confirmation and restricted substitution states retain reliability weights, so that the same demand status quantity can reflect whether the data is complete and whether the control request can continue to be executed.

[0023] Air quality status is determined by deviations from particulate matter, gases related to personnel activities, and specific target gases within the cabin. Thermal humidity status is determined by changes in temperature, relative humidity, and the load of associated equipment. Salt spray intrusion status is determined by outdoor salt spray risk, changes in inlet filter resistance, changes in indoor particulate matter, and the direction of the indoor-outdoor pressure difference. Cabin pressure difference status is determined by the pressure relationship between this cabin and adjacent cabins or the outside. Availability status is determined by the adjustable range of air valves, the remaining capacity of supply and exhaust ventilation equipment, and branch transmission records. Each status component is first converted into a dimensionless deviation according to its allowable range. When within the allowable range, the deviation remains within the baseline domain. When exceeding the boundary, the deviation increases in the direction of the boundary violation. When in an interlocked state, an independent safety deviation value is used to prevent slow temperature and humidity deviations from canceling out target gas interlocks during the same accumulation process.

[0024] In a preferred embodiment, the area control node divides the state components into a safety deviation set and an environmental deviation set. The safety deviation set receives deviations corresponding to fire protection, target gas, critical compartment pressure difference, and high salt spray risk. The environmental deviation set receives deviations corresponding to temperature, humidity, particulate matter, and associated equipment heat load. For each sampling time, the node selects the highest priority and most reliable deviation from the safety deviation set as the safety deviation item, and then sums the reliable deviations in the environmental deviation set according to compartment type and trend. The safety deviation item determines the rigid part of the demand state quantity, while the environmental deviation determines the gradual part. The combination coefficient is determined by the completeness of the reliable input within the current state frame, ensuring that gradual requests are reduced while safety requests maintain their priority when measurements are missing. The fresh air demand state quantity can be determined by the following formula.

[0025] ; in, This represents the fresh air demand status quantity for region i. This represents the number of environmental deviation components in region i that participated in this round of calculation. This represents the normalized weight of the k-th environmental deviation component. This indicates the environmental deviation component. This represents the highest priority security deviation in region i. This represents the combination coefficient of environmental deviations obtained from the completeness of the reliable input, and each... The sum is 1; when all environmental inputs are reliable and there are no security deviations, To maintain continuous adjustment, a value close to 1 is selected. This is important when the safety input enters an interlocked state or when a large amount of environmental input is missing. Decrease, make The proportion of variables in the control cycle increases, and the variables only represent the current state of the area within the same control cycle, and are not used in combination with air volume, pressure difference or equipment power.

[0026] As a calculation example, region i has 3 believable environmental deviation components. , and Take values ​​of 0.5, 0.3, and 0.2 respectively. and , Taking values ​​of 0.6, 0.4, and 0.2 respectively, the reliable input completeness is... Take 0.8, the current highest safety deviation. If we take 0.1, the weighted sum of environmental deviations is 0.46. It is 0.388; if the target gas state deviates from the same environmental condition, it will enter a higher safety level and cause... Take 0.9, and at the same time Because the security state has switched to 0.3, then The value becomes 0.768, and the regional control node switches the candidate air volume request from the environmental regulation zone to the safety treatment zone accordingly. The weight and value are only used to illustrate the calculation relationship and are determined by the cabin type, credibility record and station-level boundary during the operation of the project.

[0027] Please refer to Figure 2 , Figure 2 The horizontal axis represents the sampling window number uniformly drawn from the full operational sample of the target gas focus compartment, ranging from 1 to 500; the vertical axis represents the normalized value of the fresh air demand state quantity. The black solid line represents the demand state quantity obtained for region i under each sampling window. The dark gray dashed line represents the first operating threshold, and the light gray dotted line represents the second operating threshold. The legend is used to distinguish between them. The output sequence and two-level thresholds, along with three curves, collectively reflect the environmental deviation combination coefficients in the formula. Safety Deviations and environmental deviation weighting The combined effect of demand state quantities.

[0028] from Figure 2 As can be seen, within most sampling windows, The values ​​are mainly distributed between 0.05 and 0.12, below the first operating threshold, indicating that although environmental deviations such as temperature, humidity, particulate matter, and equipment heat load exhibit periodic fluctuations, they are generally within acceptable limits. After normalization and weighting, no sustained wind increase requests have been generated. Within this interval... Maintain a high continuous adjustment weight for environmental deviation sets. It did not become the dominant factor, so the demand status quantity showed a low-amplitude, short-cycle adjustment curve.

[0029] Around the 326th to 343rd sampling window, The presence of two significant peak values, exceeding the second operating threshold and approaching 0.8, indicates a safety deviation. It rises significantly during this stage, and at the same time The safety deviation in the formula is reduced due to the change in safety status. The proportion of [something] increases. This peak corresponds to a high-priority safety state, such as the target gas state or pressure difference direction, entering the treatment zone. Based on this, the regional control node switches the candidate air volume request from ordinary environmental regulation to safety treatment regulation.

[0030] Area control nodes When converting to candidate air volume, read the most recently verified air volume of this branch, the correspondence between the damper opening and the branch pressure difference, the currently available supply range of the common unit, and the cabin ventilation direction requirements, first based on... The difference relative to the demand baseline of this area determines the direction of increasing, decreasing, or maintaining airflow, and then the airflow increment is formed within the remaining execution range of the branch. The candidate airflow must not be lower than the lower safety limit of this area, nor higher than the upper limit allowed by the combined pressure difference of the air valve and the branch. If the target gas interlock requires exhaust, the candidate airflow supply and exhaust airflow are calculated separately and their combination is verified by the pressure difference boundary. If the critical electrical compartment requires a slight positive pressure, the direction of reducing airflow must also check the pressure of adjacent compartments and the common exhaust status. Therefore, the demand status quantity only determines the adjustment tendency, and the actual candidate value is also subject to local executability constraints.

[0031] Furthermore, a directed airflow path map is constructed based on the upstream and downstream connections of the public air ducts, the service range of the supply and exhaust air equipment, and the pressure difference coupling direction of the compartments. The area control nodes are mapped to the demand nodes in the directed airflow path map, and the public fresh air unit nodes are mapped to the supply nodes. Adjacency relationships are established only when two demand nodes share a supply path or when there is a pressure difference transmission edge. The adjacency message includes the demand difference filtered by the status flag, the candidate air volume that can be reduced within the safety boundary, and the remaining execution range of the air valve and the fan. The effective range of the adjacency message is constrained by the airflow path map version identifier. The directed airflow path map is jointly maintained by the designed air duct connection relationship and the operation feedback. The design connection determines the possible edges, and the air valve feedback, fan status, and pressure difference direction determine the currently effective edges. When the access control or fire damper status changes, only the affected local edges are updated and the airflow path map version is incremented.

[0032] In this embodiment, regional nodes sharing the same supply air duct generate supply coupling through the supply path, and regional nodes sharing the same exhaust air duct generate exhaust coupling through exhaust capacity. When there are door gaps, air transfer vents, or controlled pressure difference relationships between adjacent compartments, environmental coupling is generated through pressure difference transfer edges. Regional control nodes trace back to the nearest common supply node along the directed air path map. If the two tracing paths have the same supply segment, a supply adjacency edge is established between the two regions. If the air supply change in one region can change the pressure direction of another region through the pressure difference transfer edge, a directional pressure difference adjacency edge is established. Regions without physical coupling do not exchange air volume transfer messages even if they are in the same station-level network, to prevent the communication topology from replacing the real air path topology and forming an unexecutable collaborative result.

[0033] Adjacency messages are generated after the regional control node completes the local candidate air volume calculation. The demand difference represents the portion of the candidate air volume that is not yet satisfied between the candidate air volume and the most recently trusted executed air volume. The transferable air volume represents the portion that can be reduced while maintaining the lower safety limit of the region and the current safety deviation. The remaining execution interval represents the acceptable adjustment range of the air valve, branch, and associated supply and exhaust air equipment. Each message is bound to the sending node, receiving node, status frame version, air path diagram version, control round, and effective stage. The receiving node only uses messages that are version compatible and have consecutive control rounds. Messages that have exceeded the effective stage can still be used for fault tracing but will no longer be included in the air volume calculation. As a result, the regional node can maintain a definite selection relationship between messages that arrive at different sampling times.

[0034] Preferably, each area control node forms an adjacency allocation table based on the demand difference of its area and the transferable air volume of each adjacent area, and determines the adjacency allocation order according to safety level, wind path transmission loss and message freshness; the area control node confirms the transferable amount under the condition that the candidate air volume in its area is not lower than the safety lower limit, deducts the confirmed transferable amount from the transferable air volume of its area and adds a round identifier before sending it to the corresponding adjacent area; the receiving node only merges the confirmed amounts with the same wind path map version and consecutive rounds, discards the confirmed amounts with duplicate rounds or inconsistent versions, and submits the balance record of the candidate air volume and confirmed amount of this round to the public fresh air unit node; the allocation table also records the request source, available path and supply node, so that the same transferable air volume cannot be occupied repeatedly by two adjacent areas.

[0035] The candidate air volume between nodes is updated iteratively according to the following formula.

[0036] ; in, This represents the candidate air volume for region i in round t. Indicates the next round of candidate air volume. This indicates the number of currently valid adjacent nodes in region i. This represents the coordination coefficient between region i and its adjacent region j, determined by the wind path transmission record. This represents the fresh air demand status quantity for region i. This represents the fresh air demand state quantity of the adjacent region j. This represents the coefficient used to convert demand discrepancies into airflow correction. This represents the net transfer amount obtained by subtracting the confirmed transfer amount from the confirmed receipt amount in this round. This indicates the confirmation coefficient for net transfer volume entering the candidate air volume; after the update, it is also necessary to... The formula iteration results are restricted to the feasible range formed by the lower safety limit of this area, the upper limit of the branch road, and the public supply range, so as to avoid the formula iteration results directly crossing the physical execution boundary.

[0037] As an example of iteration, region i is currently... Taking 0.5 normalized volume units, there are 2 valid contiguous zones. Take 0.7, two Taking values ​​of 0.4 and 0.5 respectively, corresponding to... Take values ​​of 0.6 and 0.3 respectively. Take 0.2, the confirmed receiving amount in this round is greater than the confirmed transfer amount and makes Take 0.1, Taking 0.5, the demand variance item is 0.048, and the net concession item is 0.05. The value is 0.598; if the feasible upper limit of the branch road in this area is 0.56, then the area control node adopts 0.56 as the candidate air volume that can be submitted in this round, and records the remaining 0.038 as the unmet demand difference to be passed on to the subsequent rounds. The normalized value in the example is used to disclose the calculation order, and the actual air volume unit is restored to the engineering quantity when the mapping is performed.

[0038] Please refer to Figure 3 , Figure 3 The horizontal axis represents the relationship between the two axes. Figure 2 The sequence number of consecutive sampling windows from the same source ranges from 1 to 500; the vertical axis represents the normalized value of the candidate air volume in region i. The black solid line represents the candidate air volume sequence submitted after iteration between nodes, the dark gray dashed line represents the feasible lower boundary of this region, and the light gray dotted line represents the feasible upper boundary of this region. Figure 3 The corresponding candidate air volume iteration formula between nodes, where For the current round of candidate air volumes, and Together they determine how adjacent demand differences affect airflow adjustments. This indicates that the net transfer amount has been confirmed as compensation for the candidate air volume.

[0039] from Figure 3 As can be seen, during the normal sampling phase, the submitted candidate air volume mainly fluctuated between 0.50 and 0.56, significantly higher than the feasible lower boundary but lower than the feasible upper boundary, indicating that the regional nodes still retain a certain adjustment margin while meeting the safety lower limit. This phase... The adjacency correction term fluctuates periodically with changes in branch feedback and environmental demands. The net transfer volume did not show a sustained one-way increase. It also did not push the candidate air volume beyond the physically feasible range.

[0040] Around sampling windows 326 to 343, the candidate air volume showed two significant upward spikes, briefly approaching the feasible upper boundary, indicating that... Figure 2 middle Peak The conversion to wind gain correction, coupled with demand differences in adjacent areas and net concession confirmation, jointly increased [the impact]. The submitted value.

[0041] After receiving the balance records submitted by each region, the public fresh air unit node summarizes the candidate air volume, confirmed acceptance volume, confirmed transfer volume, and unmet demand difference according to the air path map version. The total confirmed acceptance volume and the total confirmed transfer volume should be offset against each other within the same supply group. The part that cannot be offset is marked as an incomplete round and returned to the relevant region for review. After the summary is approved, the public fresh air unit node forms the total air supply target based on the total candidate air volume, the filter section resistance trend, and the available range of the air supply duct. The total air supply target is then decomposed into the fan target and the duct pressure target. If the total air supply target exceeds the current available supply limit, the feasible range of the low priority area is rescaled according to the safety level and the unmet demand difference, instead of reducing it proportionally for all areas.

[0042] In a preferred embodiment, the public fresh air unit consists of multiple switchable air supply devices. The unit node maps the operational availability status, recent start / stop records, and adjustable range of each device to supply segments, and combines the total air supply capacity according to the continuity of the supply segments. Regional collaboration only uses the total supply range and does not directly specify the start / stop of a particular device. After receiving the total air supply target that has passed boundary verification, the unit node selects the supply segment required to cover the target and retains a spare segment that matches the safety lower limit of the critical compartment. When a supply segment is withdrawn, the unit node updates the supply range and airflow map version, and the regional node then cancels the unexecuted transfer confirmation in the old version and re-forms the candidate air volume within the narrowed supply range.

[0043] Furthermore, the station-level coordination node forms a hierarchical safety boundary based on the fire interlock status, target gas safety status, outdoor salt spray risk, protection level of critical electrical compartments, capacity and allowable power of public fresh air units, and configures coverage relationships for each layer of safety boundary. After each area control node completes the candidate air volume correction, it submits a result summary containing the demand status version, adjacency message version, and execution status version. The station-level coordination node projects the result summary to the corresponding safety boundary according to the coverage relationship, returns the boundary type and allowable correction direction to the boundary-crossing area, and generates the same round execution identifier for the result summary that passes the verification. The result summary also includes the wind path map version, candidate supply air volume, candidate exhaust air volume, area pressure direction, and supply occupancy, enabling the station-level verification to determine whether the cross-area combination meets the station-wide boundary.

[0044] The layered safety boundaries are established in the following order: fire protection and target gas interlock boundaries, critical electrical compartment differential pressure boundaries, salt spray and hot and humid environment boundaries, and equipment capacity and power boundaries. When the station-level coordination node verifies the result summary, it first projects the candidate air volume to the highest priority valid boundary in the coverage chain, and then uses the projection result as the input for the next layer boundary, until all valid boundaries are projected. Each projection retains the modified area identifier, modification direction, and trigger boundary. The area control node updates the air valve or fan target based on the execution identifier of the same round using the projection result of the last layer. The interlock direction that has been fixed in the previous layer will not be changed in the opposite direction by the energy consumption or environmental regulation request of the next layer. The next layer can only continue to modify within the feasible range left by the previous layer.

[0045] The fire interlock boundary determines the permissible air path for maintaining, closing, or exhausting smoke based on the fire compartment and fire damper status. The target gas boundary determines the supply and exhaust air combination based on the gas source compartment and the permissible pressure difference direction. The critical electrical compartment pressure difference boundary checks the pressure direction of each protected compartment and adjacent area after the candidate air volume is executed. The salt spray and heat and humidity boundary checks the outdoor risk status, the availability status of the filter section, and the fresh air treatment path entering the compartment. The equipment capacity and power boundary checks the execution capacity of the common unit and each branch. Boundary verification uses the regional result summary and supply group summary, without recalculating the fresh air demand state quantity or replacing the transfer between nodes. It only gives the permissible correction direction and the remaining feasible interval for the out-of-bounds quantity, so as to keep the distributed solution and the overall site safety constraints separate.

[0046] After receiving the execution identifier for the same round, the regional control node converts the final supply air target, exhaust air target, and pressure direction into the target of the air valve in this branch and the target of the local supply and exhaust air equipment. During the conversion, the execution combination that can produce the corresponding air volume change direction is selected based on the most recent reliable branch transmission record. The execution command is bound to the execution identifier, status frame version, and air path diagram version. After the air valve feedback or equipment feedback arrives, it is paired with the command version. Old feedback that cannot be paired is only written to the history record. The regional node compares the order of actual air valve changes, branch pressure difference changes, and cabin environment changes, forms an execution confirmation, and submits it to the public fresh air unit node. The unit node checks whether the total air volume change and each branch confirmation are balanced within the supply group.

[0047] Preferably, each area control node configures a master measurement sequence and an associated verification sequence for the same environmental state, and generates measurement reliability based on the consistency of the change direction of the two sequences within the sliding sampling window, sampling continuity, and physical correlation. When the master measurement sequence and the associated verification sequence are inconsistent, the corresponding state is marked as pending confirmation, and the change direction of the most recent reliable state is used to form a restricted substitution quantity with the current associated verification sequence. State components with different sampling periods are maintained or interpolated according to the common sampling time, so that each state component in the fresh air demand state quantity has the same time base and reliability version. The temperature master measurement can be verified by the load of associated equipment and the change of supply air temperature, the humidity master measurement can be verified by the outdoor humidity and the operating status of the dehumidification section, and the differential pressure master measurement can be verified by the action of the air valve and the change of branch differential pressure.

[0048] Measurement reliability is stored separately for continuity, directional consistency, and physical association components according to the data source identifier. When generating restricted substitution quantities, the regional control node first selects verification quantities with a definite transmission relationship to the state to be confirmed from the associated verification sequence, and then aligns the verification quantities to the common sampling time according to the historical delay corresponding to the transmission relationship. When there is more than one available verification quantity, a combined verification quantity is formed according to the reliability of each verification quantity and the stability of the transmission relationship. The combined verification quantity is then trimmed according to the most recent reliable state allowable interval. The trimmed record and the state flag of the state to be confirmed are written together into the fresh air demand state quantity version. Restricted substitution quantities only participate in the calculation within the predetermined effective period. After the master measurement is restored to consistency, it is replaced by a new sampling frame without writing back or modifying the original measurement record.

[0049] Specifically, sampling continuity is determined by the interval between adjacent sampling times and missing markers; consistency of change direction is determined by the sign of the increment of the main measurement and the associated verification quantity after historical time delay alignment; and physical association components are determined by whether the executed action and the environmental response conform to the branch transmission direction. When all three components are available, a complete credibility record is formed. When the continuity is normal but the direction is inconsistent, it enters the pending confirmation stage. When the main measurement is missing but there is a stable associated verification quantity, it enters the restricted substitution stage. When both the main measurement and the verification quantity are unavailable, it enters the unavailable stage. The regional control node saves the credibility record with the status frame, so that changes in requirements can be traced back to the specific data source, alignment process, trimming process, and usage stage.

[0050] Furthermore, each area control node forms a branch transfer record based on the correspondence between the valve opening feedback and the branch pressure difference change, and binds the branch transfer record to the corresponding transfer edge in the directed airflow diagram. When the branch pressure difference change direction is inconsistent with the transfer edge direction after the valve is activated, or when the air volume balance residual in the shared supply path continuously increases, the corresponding transfer edge is marked as a restricted edge. The area control nodes connected along the restricted edge stop exchanging the transferable air volume, only exchanging the demand difference and the remaining execution interval, and triggering the public fresh air unit node to re-release the available supply interval. The restricted edge retains the original design connection information but does not participate in the transfer confirmation, which facilitates re-verification after the execution feedback is restored to consistency without having to rebuild the entire airflow diagram.

[0051] The branch transmission record consists of the pre-execution status, execution command, post-execution valve feedback, branch differential pressure change, common trunk line pressure change, and adjacent area pressure change. The area control node links the data generated from the same execution according to version. It first checks whether the valve moved in the command direction, then checks whether the branch differential pressure changed in the expected direction, and finally checks whether there are any issues with the common trunk line and adjacent areas related to the airflow. Figure 1 Consistent response; if any link lacks feedback, the transmission record remains unacknowledged; if the direction is reversed, it is recorded as an anomaly; if all directions are consistent, the stability of the transmission edge is updated; stability is only used for determination. Whether the edge can participate in the next round of coordination does not change the forced air path state formed by fire protection or target gas interlocking.

[0052] When the sum of candidate air volumes in the common supply path is inconsistent with the total air volume change measured by the unit, the unit node performs branch confirmation and segment-by-segment positioning to balance the residuals. First, branches that have not been executed are excluded. Then, the pressure difference changes and transmission records of the executed branches are compared. When the residuals are concentrated in a single branch, the corresponding transmission edge is restricted. When the residuals are dispersed in the supply group, the common available supply range is shrunk and each region is requested to resubmit the result summary. During the re-coordination, the critical compartments maintain the air volume that has recently passed the boundary verification. The environmental control area reduces the candidate increments in the new feasible range to avoid the amplification of unidentified air path deviations by the iteration process.

[0053] In this embodiment, the adjacency allocation table is reconstructed at the beginning of each control round based on the current wind path map and supply interval. The table entries include the adjacent area identifier, the other party's security level, the demand difference, the transferable air volume, the path transmission loss, the message validity stage, and the confirmation status. When there is transferable air volume in the local area, areas connected by restricted edges are first excluded, and then sorted by the other party's security level. For areas with the same security level, they are sorted by path transmission loss and message freshness, and a provisional transfer amount is formed item by item. The transfer amount is deducted from the total transferable amount in the local area only after receiving the reception confirmation. The provisional amount that is not confirmed after the timeout is returned to the available pool. Therefore, asynchronous communication will not cause the transfer amount to be permanently occupied or repeatedly allocated.

[0054] Message processing employs both sending version and receiving records to ensure idempotency. Regional control nodes store the last received wind path map version, control round, and message sequence for each adjacent region. Upon receiving the same sequence, they return an existing acknowledgment without repeatedly modifying the allocation table. Upon receiving an older round, they save it as a tracking record. Upon receiving an updated wind path map version, they cancel the provisional quota of the old version that has not yet been executed. Public fresh air unit nodes use the same processing for balancing records. Supply summaries are only formed when all valid regions in the same supply group have completed submission or met safety decision conditions. The safety lower limit of unsubmitted regions is deducted from the available supply range as occupancy, ensuring that communication delays are not mistakenly interpreted as transferable capacity.

[0055] Please refer to Figure 4 Preferably, the area control node stores the execution identifiers and corresponding candidate air volumes that have recently passed the security boundary verification at each layer. When node communication is interrupted, the result summary is not verified continuously, or the reliability of the measurement in the area is lower than the availability condition, the most recent reliable candidate air volume, the minimum air volume determined by the local security level, or the interlocking air volume are selected as the downgrade target according to the anomaly type. The abnormal area publishes the non-transferable identifier and the supply occupancy of the area to the neighboring areas that can still communicate. The neighboring areas reconstruct the adjacency allocation table after deducting the supply occupancy from the available supply interval. After communication is restored, the abnormal area re-enters the security boundary projection with the current state version and does not directly use the adjacency confirmation quantity during the interruption period.

[0056] Node communication anomalies are determined by both the continuity of adjacency messages and the station-level verification response. When only a single adjacent node is lost, the corresponding adjacent edge is closed while other collaborative relationships are preserved. When a station-level coordination node is lost but regional adjacency communication is still available, new outbound directions are stopped and adjacency transfer continues within the nearest safe boundary. When all external nodes are lost, local backup control is initiated. Local backup control reads the most recent trusted environmental state, compartment safety level, and execution availability status. Critical electrical compartments maintain the protective pressure direction. Target gas interlocked areas use interlocked supply and exhaust ventilation combinations. Ordinary environmental regulation areas maintain the most recent trusted airflow and limit the range of change. All degradation actions record the source of the anomaly and the effective version.

[0057] When sensor reliability issues and communication loss occur simultaneously, the area control node does not use the restricted alternative quantities that were not confirmed before the loss of connection. Instead, it selects the candidate air volume that is consistent with the current interlock status from the most recent consecutive execution records that have passed boundary verification. If the current fire protection or target gas status is different from the most recent record, the safety interlock directly covers the most recent candidate air volume and forms the interlock air volume. The feedback of the air valve and fan is still checked by the local node in a closed loop. The supply occupancy issued by the abnormal area is a conservative occupancy between the downgrade target and the safety limit. Other areas continue to coordinate after deducting the occupancy, thereby avoiding the allocation of the surplus of the abnormal area that cannot be confirmed to other compartments.

[0058] When communication is restored, the regional control nodes first exchange node identities, current wind path map versions, last execution identifiers, and supply occupancy records during the anomaly. If the versions are inconsistent, they obtain the current valid wind path map from the station-level coordination node or the public fresh air unit node. Subsequently, they re-collect the environmental status and generate new reliability records. All adjacency confirmations saved during the anomaly are marked as historical and do not directly enter the recovery round. The regional nodes use the current... The current execution availability status and the current supply range are re-established. The result summary is re-projected through the complete security boundary and only exits the degraded state after receiving a new execution flag. The recovery process will not cause the old demand difference to be repeatedly superimposed on the current demand.

[0059] In a normal electrical load change scenario, the load on associated equipment in a high-voltage power distribution area increases, causing the temperature status to deviate continuously, while the adjacent protection zone remains within the allowable range. The environmental deviation of the former increases and becomes more severe. The latter forms a transferable air volume after maintaining the protective pressure difference; the two areas share the same air supply duct and the transfer edge is stable. After the adjacent allocation table confirms the transfer amount, the candidate air volume of the high-voltage power distribution area is increased. The public fresh air unit node synchronously checks the total supply and forms the air supply target. The station-level coordination node completes the projection within the pressure difference boundary and equipment capacity boundary of the key compartment. After execution, the branch pressure difference and temperature changes are written into the new transfer record. The whole process does not require the station-level node to resolve the demand state of each area.

[0060] In a scenario involving changes in outdoor salt spray risk, if the outdoor risk level increases and the resistance trend of a certain inlet filter branch becomes abnormal, the regional nodes serving that branch will set the salt spray intrusion status to a higher safety level, and will combine this with changes in indoor particulate matter and the direction of the indoor-outdoor pressure difference to form a [safety level]. The candidate air volume generated by the node is limited by the availability of the filter section and the protection pressure of the compartment. If reducing the fresh air of the branch will affect the positive pressure of the critical electrical compartment, the adjacent area will give up the supply margin through other available filter paths. The common unit node will reassemble the supply segments. The station-level boundary prohibits the air increase target that has not been processed by the available filter path. The execution result is jointly verified by particulate matter, pressure difference and branch feedback.

[0061] In a target gas anomaly scenario, the target gas state in the source compartment enters an interlock, and the safety deviation item causes... Upon entering the safe handling zone, regional nodes generate candidate air supply and exhaust volumes based on the chamber pressure difference requirements, and identify adjacent areas that may be affected by pressure transmission through a directional airflow map. The target gas interlock boundary fixes the exhaust direction and prohibited connection edge of the abnormal chamber, and the pressure difference boundary of the critical electrical chamber rechecks the pressure direction of adjacent protected areas. After deducting the supply occupied by the abnormal area, the public fresh air unit node issues new supply intervals to other areas. Adjacent allocation continues only on the remaining valid edges to avoid the safe exhaust request being offset by the normal temperature and humidity demand.

[0062] In fire interlocking scenarios, fire compartment signals and fire damper status directly update the directional airflow map, marking edges that need to be closed as forcibly unavailable and edges that allow smoke exhaust as interlocked edges. Relevant area nodes stop the transfer confirmation in the old version and form candidate supply and exhaust air volumes consistent with the fire status. Station-level coordination nodes place the fire boundary at the top of the coverage chain. Any heat and humidity, salt spray, or power boundaries can only be corrected within the feasible range left by the fire boundary. After receiving the execution mark, area nodes confirm the action of fire dampers and supply and exhaust air equipment according to local feedback. When communication is lost, the same direction is maintained by local interlock input. After the fire status is lifted, the airflow map is reconstructed and a new round of boundary verification is completed.

[0063] During filter maintenance, the public fresh air unit node removes the supply segment corresponding to the deactivated filter path from the available supply range and updates all transmission edges passing through that path. Affected areas will no longer list the old branch capacity as a remaining execution range. If a backup filter path exists, the node re-establishes adjacency relationships and transmission loss records based on the new airflow diagram. The safety lower limit of critical compartments is reserved as a priority for occupancy, while ordinary areas are maintained as currently... Adjust the candidate air volume; after maintenance, first verify the feedback of the damper, branch pressure difference, and common main pipe response by executing commands with low variation amplitude. After confirming consistency of the transmission records, restore the stability of the corresponding side before allowing it to participate. Calculation and airflow transfer.

[0064] Before the system is put into operation, an initial directional airflow map is generated based on the actual duct connections, fire compartments, service range of supply and exhaust air equipment, and pressure difference relationships between compartments. The environmental status to be collected, the associated verification sequence, the compartment safety level, and the branch execution object are bound to each area. During the commissioning process, small valve actions, supply air changes, and exhaust air changes are executed respectively, and the branch pressure difference, common main duct pressure, and pressure direction of adjacent compartments are recorded to form the initial branch transmission record. The state deviation mapping only uses the allowable range and change direction, and does not directly apply the engineering quantity of one compartment to another compartment. The weights, combination coefficients, and synergy coefficients in the formula are generated from the commissioning records, credibility completeness, and airflow stability, and are bound to the compartment identifier and airflow map version in the configuration version.

[0065] During operation, the regional control nodes process data in a cyclical manner, following the sequence of status frame generation, reliability assessment, demand status quantity calculation, candidate air volume formation, adjacency message exchange, transfer confirmation, result summary submission, boundary projection, execution feedback, and transmission record update. Each step retains both input and output versions. The public fresh air unit nodes maintain air volume balance within the supply group, while the station-level coordination nodes only maintain safety boundaries and execution identifiers. The monitoring interface reads the status records, demand differences, supply occupancy, boundary violation types, and degradation statuses already formed by each node, and directly modifies intermediate iteration quantities without using the interface. When manual intervention is required, the operation command is issued as a new safety boundary version and enters the next control cycle after being confirmed by the node.

[0066] In a preferred embodiment, each area control node adopts an operation mode that combines event triggering and periodic verification. When the environmental state exceeds the allowable range, the interlocking state changes, the wind path map version changes, or the execution feedback direction is abnormal, a new status frame is immediately generated. When the environmental quantity remains stable, the measurement continuity, message validity stage, and supply occupancy are still checked periodically. The event triggering frame can start the adjacency coordination in advance, but it must not skip the current wind path map version check and station-level boundary projection. The periodic verification frame is used to clean up expired temporary quantities, check incomplete executions, and update the most recently trusted records. The two types of status frames enter the same version sequence according to the generation time. The newer interlocking frame can invalidate the ordinary environmental adjustment frames that have not yet been executed, while the old frames that have already been executed retain feedback records for branch transmission relationship verification.

[0067] When a regional node determines that an adjacency coordination can end, it simultaneously checks the unmet demand difference in its region, the unconfirmed provisional quantity in the adjacency allocation table, the supply group balance residual, and the direction of candidate air volume change. If the unmet demand difference has entered the feasible range of the region and there are no unconfirmed provisional quantities, it submits a stable result summary. If the public supply has reached its limit but there is still a demand difference in the low priority area, it submits a restricted result summary. If there are still unconfirmed quantities after the effective communication phase ends, it cancels the corresponding provisional quantity and submits an incomplete result summary. The station-level coordination node projects the three types of summaries using the same safety boundary. The unconfirmed quantities in the incomplete summary are not included in the available supply, and the demand difference in the restricted summary is retained as an operation record without forcing public units to cross the capacity boundary.

[0068] To limit frequent reverse valve actions caused by repeated changes in environmental measurements at the edges of permissible intervals, the area control node compares the demand direction, the most recently executed direction, and branch transmission records in consecutive state frames. Only when the demand direction remains consistent or the safety level increases will the candidate airflow change be expanded in the next round. If the demand direction reverses but remains at the same safety level, the unexecuted candidate increments are consumed first, and then a request for the opposite direction is formed based on the new state frame. This process remains unchanged. The calculation results do not add independent thresholds outside the station-level boundary. Instead, the candidate air volume update order is determined by using the already saved execution version and change direction, so that the valve action, branch pressure difference response and environmental status feedback can be paired according to the same causal chain.

[0069] When an offshore substation experiences maintenance door openings, temporary personnel entry, or partial equipment shutdowns, the access control status and equipment operating status are treated as version events of the airflow diagram and thermal humidity status. Maintenance door openings cause the associated differential pressure transmission edge to enter a pending confirmation phase and temporarily reduce the transferable airflow in critical compartments. Personnel entry causes the air quality component of the corresponding compartment to participate in the current demand status quantity. Partial equipment shutdowns update the associated thermal load verification sequence but do not directly delete the main temperature measurement. After maintenance is completed, the regional node waits for access control to be restored, pressure direction to be reconfirmed, and equipment status frames to stabilize before restoring the transmission edge and associated verification relationship. This prevents short-term operational status from being mistaken for long-term airflow or environmental load changes.

[0070] The system adopts versioned release for changes to control configurations. When changes occur in cabin type, permitted interval, safety level, airflow connection, verification sequence association, and execution object, the station-level coordination node generates a configuration version to be effective. Each area control node checks whether its local data source and execution object can be mapped to the new version, and the public fresh air unit node checks whether the supply group and airflow diagram are complete. Only after all affected nodes have completed mapping confirmation will the new configuration replace the old version in the agreed control round. Areas that have not completed confirmation continue to use the old configuration and are marked as not eligible to participate in cross-version transfer. The old version confirmation that has not yet been executed during configuration switching is revoked, and the most recently trusted execution record continues to serve as the basis for abnormal degradation.

[0071] The control operation review starts with the execution identifier and reads the pre-command state frame, adjacency allocation table, supply group balance record, boundary projection record of each layer, and post-command execution confirmation. If the direction of change in the cabin environment is inconsistent with the candidate air volume direction, the system first checks whether the valve feedback and branch pressure difference prove that the command has reached the physical branch, and then checks whether the master measurement and associated verification sequence have the same time base. If the physical execution is consistent but the measurement direction is abnormal, the system only reduces the credibility of the corresponding data source and regenerates the restricted substitution quantity. If the physical execution is inconsistent, the system restricts the corresponding transmission edge and shrinks the supply interval. If the boundary projection modification direction is inconsistent with the local execution direction, the system stops the execution identifier and requests the station-level coordination node to reissue the allowed correction direction. The review result is written to the source record of the next state frame. The system does not directly modify the completed coordination rounds and boundary records to ensure that the fault location process does not destroy the version relationship of the control history.

[0072] In this embodiment, the control record establishes an association index based on the region status frame, adjacent coordination round, station-level boundary projection round, and execution confirmation round. Any air volume action can be traced back to the corresponding execution identifier. Net transfer volume Demand state quantity Safety Deviations And the credibility of the original data source; when the running results are inconsistent with the expected direction, maintenance personnel can distinguish whether the deviation comes from the measurement credibility, wind path map version, transfer confirmation, boundary projection or execution feedback, and only restrict the corresponding data source, transfer edge or regional node, while the remaining control areas continue to run using the current valid version, so that normal adjustment, abnormal degradation and recovery reentry share the same set of verifiable data chain and control boundaries.

Claims

1. A method for intelligent control of distributed fresh air at an offshore substation, characterized in that, include: Area control nodes are configured according to the cabin and its fresh air branch. Each area control node collects the cabin environmental status, branch execution status and associated electrical equipment load to form a fresh air demand status quantity with safety level and allowable adjustment range, and converts the fresh air demand status quantity into the candidate air volume of the area. Based on the air path coupling relationship between fresh air branches, establish node adjacency relationships, and control nodes in adjacent areas exchange demand differences, transferable air volume, and execution capabilities, and iteratively correct candidate air volumes; The public fresh air unit node adjusts the total air supply capacity according to the corrected candidate air volume of each area, and the station-level coordination node issues the safety boundary and verifies the air volume results of each area control node; When the area control node or node communication is abnormal, the abnormal area performs local degradation control based on the nearest trusted boundary, and the remaining areas redetermine the transferable air volume based on the abnormality identifier.

2. The intelligent control method for distributed fresh air in an offshore substation according to claim 1, characterized in that, Each area control node generates air quality status, heat and humidity status, salt spray intrusion status, cabin pressure difference status, and execution availability status, respectively, and encodes the measurement reliability and change trend corresponding to each status as status labels; The state components participating in this control are selected according to the safety level order issued by the station-level coordination node. The deviation of the state components from their respective allowable intervals is mapped to the common demand domain. The maximum safety deviation and cumulative environmental deviation in the common demand domain are combined into the fresh air demand state quantity. The fresh air demand state quantity is also bound to the sampling time, cabin identifier and branch identifier.

3. The intelligent control method for distributed fresh air in an offshore substation according to claim 1, characterized in that, Based on the upstream and downstream connections of the public air duct, the service range of the supply and exhaust air equipment, and the coupling direction of the chamber pressure difference, a directional air path map is constructed. The regional control node is mapped to the demand node in the directional air path map, and the public fresh air unit node is mapped to the supply node. Adjacency is established only when two demand nodes share a supply path or when a pressure difference transmission edge exists. The adjacency message includes the demand difference filtered by the status flag, the candidate air volume that can be reduced within the safety boundary, and the remaining execution range of the air valve and fan. The effective range of the adjacency message is constrained by the air path map version identifier.

4. The intelligent control method for distributed fresh air in an offshore substation according to claim 1, characterized in that, The station-level coordination node will form a hierarchical safety boundary based on the fire interlock status, target gas safety status, outdoor salt spray risk, protection level of critical electrical compartments, capacity and allowable power of public fresh air units, and configure a coverage relationship for each layer of safety boundary. After each regional control node completes the candidate air volume correction, it submits a result summary containing the demand status version, the adjacency message version, and the execution status version. The station-level coordination node projects the result summary to the corresponding safety boundary according to the coverage relationship, returns the boundary type and allowed correction direction to the out-of-bounds area, and generates the same round execution identifier for the result summary that passes the verification.

5. The intelligent control method for distributed fresh air in an offshore substation according to claim 2, characterized in that, Each regional control node configures a master measurement sequence and an associated verification sequence for the same environmental state, and generates measurement reliability based on the consistency of the change direction of the two sequences within the sliding sampling window, the sampling continuity, and the physical correlation. When the master measurement sequence is inconsistent with the associated verification sequence, the corresponding state flag is set to pending confirmation, and the change direction of the most recent reliable state is used to form a restricted substitution quantity with the current associated verification sequence; For state components with different sampling periods, maintain or interpolate according to the common sampling time, so that each state component in the fresh air demand state quantity has the same time base and confidence version.

6. The intelligent control method for distributed fresh air in an offshore substation according to claim 3, characterized in that, Each area control node forms a branch transmission record based on the correspondence between the feedback of the air valve opening and the change of the branch pressure difference, and binds the branch transmission record to the corresponding transmission edge in the directed wind path diagram; When the branch pressure difference changes in the direction of the damper action are inconsistent with the direction of the transmission edge, or when the air volume balance residual in the shared supply path increases continuously, the corresponding transmission edge is marked as a restricted edge. The area control node connected along the restricted edge stops exchanging the transferable air volume, only exchanging the demand difference and the remaining execution interval, and triggering the public fresh air unit node to republish the available supply interval.

7. The intelligent control method for distributed fresh air in an offshore substation according to claim 1, characterized in that, Each regional control node forms an adjacency allocation table based on the demand difference of its own region and the transferable air volume of each adjacent region, and determines the adjacency allocation order according to the safety level, wind path transmission loss and message freshness. The regional control node confirms the transfer volume under the condition that the candidate air volume in the region is not lower than the safety lower limit, deducts the confirmed transfer volume from the transferable air volume in the region and sends it to the corresponding adjacent region with a round identifier attached. The receiving node only merges confirmations with the same wind path map version and consecutive rounds, discards confirmations from duplicate rounds or with inconsistent versions, and submits a balance record of candidate air volume and confirmation volume for the current round to the public fresh air unit node.

8. The intelligent control method for distributed fresh air in an offshore substation according to claim 4, characterized in that, The layered safety boundaries are established in the following order: fire protection and target gas interlock boundary, critical electrical compartment pressure difference boundary, salt spray and hot and humid environment boundary, and equipment capacity and power boundary. When the station-level coordination node verifies the result summary, it first projects the candidate air volume to the highest priority valid boundary in the coverage chain, and then uses the projection result as the input of the next layer boundary, until all valid boundaries are projected. Each projection retains the modified area identifier, modification direction, and trigger boundary. The area control node updates the air valve or fan target based on the last layer projection result according to the execution identifier of the same round.

9. The intelligent control method for distributed fresh air in an offshore substation according to claim 5, characterized in that, The measurement confidence is stored in the continuity component, direction consistency component and physical association component according to the data source identifier. When the area control node generates the restricted substitution quantity, it first selects the verification quantity with a definite transmission relationship with the state to be confirmed from the associated verification sequence, and then aligns the verification quantity to the common sampling time according to the historical delay corresponding to the transmission relationship. When there is more than one available verification quantity, a combined verification quantity is formed according to the credibility and stability of the transmission relationship of each verification quantity. The combined verification quantity is then trimmed according to the most recent credible state allowable interval. The trimmed record and the state flag of the unconfirmed state are written together into the fresh air demand state quantity version.

10. The intelligent control method for distributed fresh air in an offshore substation according to claim 6, characterized in that, The area control node stores the execution identifier and corresponding candidate air volume that have recently passed the security boundary verification of each layer. When the node communication is interrupted, the result summary is not verified continuously, or the reliability of the measurement in this area is lower than the usable condition, the most recent reliable candidate air volume, the minimum air volume determined by the local security level, or the interlocking air volume are selected as the downgrade target according to the anomaly type. An abnormal region publishes a non-transferable identifier and its local supply occupancy to adjacent regions that can still communicate. The adjacent regions then reconstruct their adjacency allocation tables after deducting the supply occupancy from the available supply range. After communication is restored, the abnormal region re-enters the security boundary projection with the current state version, without directly using the adjacency acknowledgments from the interruption period.

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