Multi-path air compressor linkage control system with exhaust load balancing

Abstract

This invention relates to the field of intelligent control of air compression equipment, specifically a multi-channel air compressor linkage control system for balanced exhaust volume load. The system includes a status acquisition module, an execution control module, and a control center. The status acquisition module collects operating status data of each air compressor and pipeline pressure data. The operating status data includes instantaneous active power and exhaust temperature. The control center pre-stores the rated parameters of the air compressors, calculates the real-time exhaust volume of each air compressor based on the operating status data and rated parameters, evaluates the dynamic effective exhaust contribution index, predicts compensation for air volume gaps, constructs an equipment status matrix, selects target air compressor combinations, and generates equipment control commands which are then sent to the execution control module to achieve balanced exhaust volume load management.

Description

Technical Field

[0001] This invention relates to the field of intelligent control of air compression equipment, specifically a multi-channel air compressor linkage control system for balanced exhaust volume load. Background Technology

[0002] As an important component of centralized gas supply stations in factories, air compressor linkage control systems are widely used in continuous gas consumption scenarios such as automobile manufacturing, machinery processing, and electronic assembly. To ensure the stability of pipeline gas supply and the reliability of equipment operation, it is usually necessary to uniformly schedule and control the air compressor equipment consisting of multiple air compressors and the corresponding pipeline equipment, and to adjust the start-up, shutdown, loading, and load distribution status of each air compressor in a timely manner according to changes in pipeline pressure. However, when controlling multiple air compressors in a coordinated manner, it is necessary to accurately determine the actual air supply capacity of each air compressor under the current operating conditions and further determine the relationship between the replenishment air demand and the unit allocation. In existing technologies, methods such as scheduling based on fixed start-stop sequences, single pressure threshold triggering, or rated discharge volume are often used. Although this control method is simple to implement, it easily overlooks the actual differences between different units in terms of operating years, mechanical wear, exhaust temperature, power fluctuations, and number of loading cycles. At the same time, if the judgment of replenishment air demand is based solely on the pipeline pressure value at a certain moment, it usually has a significant lag and is difficult to reflect the actual air volume gap corresponding to the pressure drop trend under the total pipeline volume conditions. This not only easily leads to unbalanced load distribution but may also cause untimely air supply response and overload fatigue operation of some units, thereby affecting the stability of pipeline pressure and the service life of air compressor equipment. Summary of the Invention

[0003] The purpose of this invention is to provide a multi-channel air compressor linkage control system with balanced exhaust volume load, solving the following technical problems: avoiding indiscriminate static allocation based solely on static nameplate parameters and ignoring excessive equipment usage caused by long-term mechanical wear; and enabling air supply to be organized according to the actual physical state and real-time effective contribution capacity of the unit, allowing different models to undertake more matched load allocation tasks, thereby achieving a synergistic balance between air supply stability, execution responsiveness, and equipment life protection. The purpose of this invention can be achieved through the following technical solutions: A multi-channel air compressor linkage control system with balanced exhaust volume and load is used to control air compressor equipment and pipeline equipment consisting of multiple air compressors, including: The status acquisition module is connected to both the air compressor equipment and the pipeline equipment to collect the operating status data of each air compressor and the pipeline pressure data of the pipeline equipment. The operating status data includes instantaneous active power and exhaust temperature. The execution control module is connected in communication with the air compressor equipment and is used to control the operating status of the air compressor equipment; The control center is connected to the status acquisition module and the execution control module respectively. It has pre-stored the rated parameters of the air compressor, and is used to process the operating status data and pipeline pressure data to generate equipment control commands. The equipment control commands are then sent to the execution control module for load balancing management of the exhaust volume. The control center is used to: calculate the real-time exhaust volume of each air compressor based on operating status data and rated parameters of the air compressor; evaluate the dynamic effective exhaust contribution index of each air compressor based on operating status data; and predict the compensation air volume gap based on pipeline pressure data. Based on the dynamic effective exhaust contribution index of each air compressor, an equipment state matrix is ​​constructed. Target air compressor combinations are selected in the equipment state matrix in descending order of dynamic effective exhaust contribution index until the total real-time exhaust volume of the target air compressor combination is greater than or equal to the compensation air volume gap. Equipment control commands are then generated based on the target air compressor combination.

[0004] Optionally, the operating status data also includes the cumulative number of loading cycles; the control center is used to calculate the power-time change rate based on instantaneous active power and the temperature increment rate based on exhaust temperature; the control center has preset weights corresponding to the power-time change rate, temperature increment rate and cumulative number of loading cycles respectively.

[0005] Optionally, the control center pre-stores the total volume data of the pipeline network; The control center is used to calculate the pressure drop slope based on pipeline pressure data; The control center is also used to calculate the compensation gas volume gap by combining the pressure drop slope and the total volume of the pipeline network.

[0006] Optionally, the air compressor equipment includes variable frequency air compressors and fixed frequency air compressors; the equipment control commands include frequency adjustment commands and load signal commands; the control center has pre-stored load distribution ratios; The control center is used to decompose the compensation air volume gap into basic load and transient fluctuation load according to the load distribution ratio, and to allocate the basic load to the air compressor with the highest dynamic effective exhaust contribution index in the target air compressor combination to generate a loading signal command. Then, it selects the variable frequency air compressor with the highest dynamic effective exhaust contribution index from the remaining air compressors and allocates the transient fluctuation load to the variable frequency air compressor to generate a frequency adjustment command.

[0007] Optionally, the control center has a pre-stored slope convergence range; the control center is also used to monitor the convergence status of the pressure drop slope in real time after issuing equipment control commands. The control center is used to maintain the load distribution status of the target air compressor combination when the pressure drop slope converges to the slope convergence range; The control center is also used to trigger a negative feedback mechanism when the pressure drop slope does not converge to the slope convergence range; the negative feedback mechanism includes: reducing the dynamic effective exhaust contribution index of each air compressor in the target air compressor combination, and transferring the load to the next air compressor in the next order of the equipment state matrix in the next calculation cycle.

[0008] Optionally, the control center has a pre-stored extreme drop threshold; a bypass hard-wired circuit is also provided between the execution control module and the air compressor equipment. The control center is used to generate equipment control commands by combining the equipment state matrix and the target air compressor when the absolute value of the pressure drop slope is less than or equal to the extreme drop threshold. The control center is also used to activate the hard-wired cascaded full-open mode based on the bypass hard-wired circuit when the absolute value of the pressure drop slope is greater than the extreme drop threshold, forcing all online air compressors to run at full load.

[0009] Optionally, the control center also includes a historical database with pre-stored attenuation thresholds; The control center is used to continuously store the dynamic effective exhaust contribution index of each air compressor into the historical database to generate historical decay curves; The control center is also used to predict equipment status based on historical attenuation curves, extract the attenuation rate of historical attenuation curves within a preset observation window, and determine abnormal attenuation and generate equipment maintenance warning instructions when the absolute value of the attenuation rate of historical attenuation curves is greater than the attenuation threshold; and determine normal attenuation and maintain the current operating status when the absolute value of the attenuation rate of historical attenuation curves is less than or equal to the attenuation threshold.

[0010] The beneficial effects of this invention are: 1. This invention introduces the cumulative number of loading cycles, power-time change rate, and temperature increment rate, and assigns preset weights to them. The system comprehensively quantifies the current thermal state, working state, and historical mechanical fatigue state of the unit. This avoids the excessive use of units whose monitored operating parameters are normal but are actually on the verge of mechanical fatigue. 2. The system of this invention combines the total volume data of the pipeline network with the pressure drop slope of the pipeline network to accurately transform the abstract pressure drop trend into a specific compensation gas volume gap; this mechanism overcomes the lag of traditional single pressure threshold alarms and realizes early identification and feedforward compensation of sudden gas consumption gaps. 3. The system of this invention scientifically divides the compensation air volume gap into basic load and transient fluctuation load, which are respectively assigned to the ordinary unit and the variable frequency air compressor with the best overall condition; this allows different types of air compressors to give full play to their advantages according to their respective mechanical characteristics, and reduces mechanical losses caused by frequent start-stop while ensuring system response speed; 4. After issuing control commands, the system of this invention will monitor the convergence status of the pressure drop slope in real time. If it does not converge as expected, it will trigger a negative feedback mechanism to downgrade the contribution ranking of the relevant units and transfer the load. This forms a closed-loop verification link, which effectively corrects the deviation between the actual exhaust capacity of the units and the theoretical evaluation, and avoids the long-term solidification of erroneous scheduling. 5. In response to extreme pressure loss conditions such as pipeline rupture, the present invention sets an extreme drop threshold for the system. When the pressure drops sharply, the system can bypass conventional software scheduling and directly trigger the cascaded full-open mode through the bypass hard-wired circuit, forcing the online air compressor to run at full load, providing deterministic bottom-level pressure protection for industrial sites. 6. The control center of this invention continuously stores the dynamic effective exhaust contribution index into the historical database and generates historical decay curves. By monitoring the decay rate, the system can accurately identify abnormal performance degradation that does not conform to the normal aging pattern and generate maintenance warnings, thus realizing seamless connection between real-time gas supply linkage and long-term predictive maintenance of equipment. Attached Figure Description

[0011] Other features, objects, and advantages of the invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the multi-channel air compressor linkage control system for balancing exhaust volume and load provided in the embodiments of this application. Detailed Implementation

[0012] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0013] Please see Figure 1 A multi-channel air compressor linkage control system with balanced exhaust volume load is used to control air compressor equipment and pipeline equipment composed of multiple air compressors. It includes: a status acquisition module, which is communicatively connected to the air compressor equipment and pipeline equipment respectively, and is used to collect the operating status data of each air compressor and the pipeline pressure data of the pipeline equipment; the operating status data includes instantaneous active power and exhaust temperature; The execution control module is connected in communication with the air compressor equipment and is used to control the operating status of the air compressor equipment; The control center is connected to the status acquisition module and the execution control module respectively. It has pre-stored the rated parameters of the air compressor, and is used to process the operating status data and pipeline pressure data to generate equipment control commands. The equipment control commands are then sent to the execution control module for load balancing management of the exhaust volume. The control center is used to: calculate the real-time exhaust volume of each air compressor based on operating status data and rated parameters of the air compressor; evaluate the dynamic effective exhaust contribution index of each air compressor based on operating status data; and predict the compensation air volume gap based on pipeline pressure data. Based on the dynamic effective exhaust contribution index of each air compressor, an equipment state matrix is ​​constructed. Target air compressor combinations are selected in the equipment state matrix in descending order of dynamic effective exhaust contribution index until the total real-time exhaust volume of the target air compressor combination is greater than or equal to the compensation air volume gap. Equipment control commands are then generated based on the target air compressor combination.

[0014] This embodiment provides a multi-channel air compressor linkage control mechanism for balanced exhaust volume load; specifically, this embodiment takes the centralized air supply station of an automobile stamping assembly plant as the unified main line scenario. The station continuously supplies air to six stamping production lines, welding fixture cylinders and pre-painting treatment valve groups. The station is equipped with four twin-screw air compressors, a main pipeline, several branch air storage tanks and pipeline pressure transmitters. The four air compressors may include units with the same power rating but different years of operation. Therefore, even if the nameplate parameters are similar, the actual exhaust capacity of each unit under the same frequency or loading conditions is not completely consistent. Specifically, the status acquisition module is connected to each air compressor and the main pipeline for communication; for the air compressor side, it is preferred to collect operating status data, including instantaneous active power and exhaust temperature, through smart meters, temperature sensors and unit controllers. For the pipeline network side, it is preferable to collect pipeline pressure data through a pipeline network pressure transmitter; the control center is preferably a programmable logic controller or an industrial control computer, and pre-stores rated parameters such as rated power, rated displacement, rated speed range, and loading / unloading working boundaries for each air compressor; The execution control module preferably includes an output interface connected to the frequency converter, loading solenoid valve, unloading valve, and start-stop circuit, which is used to implement the equipment control commands generated by the control center to specific units; In terms of physical mechanism, instantaneous active power is not just an electrical quantity; it reflects the level of mechanical work done by the motor in the current compression process. Exhaust temperature is not just a temperature value; it is a comprehensive result of compression efficiency, internal leakage, cooling status, and lubrication status within the compression chamber. When a unit's volumetric efficiency decreases due to increased rotor clearance, scale buildup in the cooler, or deterioration in lubrication, it manifests as increased power consumption per unit of actual gas volume and an exhaust temperature rise rate greater than the preset temperature rise threshold. Therefore, this embodiment does not directly take the nameplate exhaust volume as the current actual exhaust capacity. Instead, it obtains the real-time exhaust volume of each unit based on the operating status data and rated parameters. The control center has a built-in volumetric efficiency reduction model. Based on the deviation between the instantaneous active power and the rated power of the air compressor, as well as the temperature rise of the exhaust temperature compared with the reference temperature, it dynamically calculates the current volumetric efficiency reduction factor and multiplies the rated exhaust volume of the air compressor with the reduction factor to obtain the real-time exhaust volume of the air compressor. The volumetric efficiency degradation calculation model includes a preset deviation-reduction coefficient mapping table. When the deviation between the instantaneous active power and the rated power of the air compressor is greater than a preset threshold and the exhaust temperature is higher than the reference temperature, the volumetric efficiency reduction coefficient is reduced according to a preset ratio. The deviation-reduction coefficient mapping table and the preset ratio can be obtained by fitting and calibrating historical test data. For example, when the power deviation is greater than 10% and the exhaust temperature is 5°C higher than the reference temperature, the reduction coefficient is set to 0.95.

[0015] Furthermore, the dynamic effective exhaust contribution index is evaluated based on instantaneous active power and exhaust temperature; this index is used to characterize the ability of a unit to stably contribute how much effective compressed air for each load at the current moment. In terms of control process, the control center first identifies whether there is a gas supply gap trend in the current pipeline equipment based on pipeline pressure data, and then predicts the compensation gas volume gap. The control center constructs an equipment status matrix based on the dynamic effective exhaust contribution index of each unit. This matrix can be understood as a real-time updated unit capacity ranking table. For example, the matrix records the current ranking of the first, second, third, and fourth air compressors and their corresponding real-time exhaust volume. The control center starts by selecting units with high contribution indices and gradually combines them into target air compressor combinations until the total real-time exhaust volume of the combination can cover the current compensation demand. Then, the control center combines the current status of the unit to generate equipment control commands, and issues them through the execution control module to achieve balanced control of exhaust load. In the fault-tolerant control mechanism, if the power data of a certain unit is interrupted for a short time, the temperature sensor is distorted, or the communication link is abnormal, the control center can temporarily mark the unit as having decreased reliability and not make it a priority scheduling target. Instead, the remaining units with complete data will undertake the main regulation tasks. If a pressure sensor malfunction causes pipeline pressure data to be unavailable, the system will enter a conservative operation mode, maintaining only the current safe status of the units already loaded on site and restricting new frequent start-stop actions. The compensation gas volume gap will be recalculated once the pressure measurement is restored. If the dynamic effective exhaust contribution index of all candidate units is low, the control center can still select the relatively stable units to participate in gas supply according to the principle of safety priority, without causing pipeline pressure loss due to simply pursuing efficiency. During the die-changing phase of the first production shift at the aforementioned automotive stamping plant, multiple pneumatic clamps and purging branches used air simultaneously within a preset time window, resulting in a continuous downward trend in pipeline pressure. At this time, although the first air compressor is a unit that has been running for longer than the preset time threshold, its current active power is stable and its exhaust temperature is normal, indicating that its volumetric efficiency is higher than the preset benchmark value; although the second air compressor is online, its exhaust temperature is consistently high, reflecting that its cooling margin is lower than the preset safety lower limit; the third air compressor is in standby mode; and the fourth air compressor has just undergone a load switching. Based on this, the control center prioritizes the inclusion of the first and third air compressors into the target air compressor combination, rather than simply calling the second air compressor according to a fixed start-stop sequence, so that the air replenishment action is closer to the actual mechanical state of each unit. The purpose of this step is to establish a linkage control basis based on the actual physical state, so that the system no longer relies on static nameplate parameters for static indiscriminate allocation, but organizes gas supply according to the real-time effective contribution capacity of the unit, thereby achieving a balance between pipeline pressure stability and equipment life protection.

[0016] In a preferred embodiment of the present invention, the operating status data further includes the cumulative number of loading cycles; the control center is used to calculate the power-time change rate based on the instantaneous active power and the temperature increment rate based on the exhaust temperature; the control center has preset weights corresponding to the power-time change rate, the temperature increment rate and the cumulative number of loading cycles respectively.

[0017] This embodiment provides a refined evaluation mechanism for the dynamic effective exhaust contribution index. Specifically, in the aforementioned centralized gas supply station of the automobile stamping plant, judging the priority of the unit based solely on instantaneous active power and exhaust temperature can reflect the thermodynamic and working state at the current moment, but may still overlook the long-term factor of mechanical fatigue under the working conditions of continuous production and frequent start-stop shifts. In particular, even if the exhaust temperature of some units is currently within the normal range and the power is not abnormal, if the number of loading cycles is high for a long period of time, the intake valve, contactor, unloading mechanism and other parts are more likely to be on the verge of fatigue. Specifically, in this embodiment, the cumulative loading cycle count is further introduced into the operating status data, and the control center pre-stores preset weights corresponding to the power time change rate, temperature increment rate and cumulative loading cycle count respectively. The power time change rate here reflects the stress response characteristics of the unit when facing load changes: if the power rises too fast and fluctuates frequently, it usually indicates that there is a large mechanical shock or internal resistance change in the unit during load switching. Temperature increment rate reflects the evolution speed of the unit's exhaust thermal state: under the same load conditions, a unit with a faster temperature rise often means a decrease in heat dissipation capacity, an increase in internal leakage, or a deterioration in lubrication condition; the cumulative number of loading cycles directly corresponds to the historical wear and tear of mechanical actions, and has practical indicative significance for the life of valve groups and contactors of power frequency units. In terms of data formation, the control center does not need to perform highly complex iterative calculations. Instead, it observes the changing trends of the power curve and temperature curve within a continuous sampling window and combines the cumulative number of loading cycles to form a scalar form of dynamic effective exhaust contribution index. To avoid a single parameter dominating the entire evaluation result due to the completely different physical dimensions of the power time change rate, temperature increment rate, and cumulative loading cycle number, the preset weights stored in the control center have been pre-uniformed in terms of dimensions and configured with positive and negative polarities. The specific control logic is as follows: considering that the larger the values ​​of these three indicators, the more severe the shock, heat load or fatigue the unit is subjected to, the preset weights of the corresponding power time change rate, temperature increment rate and cumulative loading cycle number stored in the control center are configured as corresponding negative coefficients. The control center directly multiplies the real-time calculated power time change rate, temperature increment rate and the acquired cumulative loading cycle number by their corresponding negative preset weights and then performs algebraic summation. At the same time, to avoid the final value being negative, the system presets a reference constant. The control center adds the summation result to this reference constant to obtain the dynamic effective exhaust contribution index in scalar form. The specific formula for algebraic summation is as follows: ; in, The contribution index to dynamic effective exhaust gas. As a reference constant, These are the corresponding power time change rates. Temperature increment rate and cumulative loading loop count Preset weights; In one specific embodiment, the baseline constant can be set to 100, and the preset weights for the power-time change rate, temperature increment rate, and cumulative load cycle count can be set to -0.5, -1.2, and -0.01, respectively. This normalizes the multi-dimensional state data into a percentage-based health scalar, which can be understood as a comprehensive quantitative representation of a unit's current overall health and effective gas supply capacity. , , The numerical value is obtained by fitting and calibrating historical operating data based on the degree of attenuation of volumetric efficiency when the corresponding physical quantity reaches the equipment alarm threshold, thereby ensuring the objective physical basis of the index evaluation; this scalar can be understood as a comprehensive quantitative representation of the current overall health status and effective gas supply capacity of a unit. Taking into account three state dimensions—the power-time change rate, the temperature increment rate, and the degree of excessive cumulative load cycles—of the first, second, and third air compressors, if the first air compressor shows stable performance in terms of power change rate and temperature increment rate, and has a low cumulative load cycle load, then its negative attenuation is less and its overall scalar value is higher. If the temperature increment rate of the second air compressor is greater than the preset increment threshold and the cumulative number of loading cycles is greater than the preset number of cycles threshold, then its negative decay is large and the overall scalar is low; the purpose of this process is to enable the control center to simultaneously acquire and process three types of objective states: the current thermal state, the current working state, and the historical fatigue state. In the fault-tolerant control mechanism, if the cumulative load cycle counter of a unit is replaced due to shutdown maintenance, the control center can read the most recent reset time in the maintenance record, mark the unit as being in the process of rebuilding the counting baseline, and increase the dependence on dynamic quantities such as power and temperature for a period of observation. If power or temperature sampling fluctuates briefly, the control center should prioritize using the smooth trend within a continuous window, rather than immediately reducing the unit's ranking based on a single transient abnormal extreme point, in order to avoid control logic identification deviations caused by grid fluctuations or instantaneous gas release interference. During the second production shift of the aforementioned stamping plant, the second air compressor had just undergone multiple loading and unloading cycles. Although the pipeline pressure was normal at this time and the instantaneous power of the second air compressor was not obviously abnormal, its exhaust temperature dropped more slowly and the cumulative loading cycles were significantly higher than those of the other units in the same station. The control center calculates that the dynamic effective exhaust contribution index of the second air compressor is low, so that subsequent air consumption fluctuations are preferentially handled by the first or third air compressor, thereby avoiding the second air compressor from continuing to suffer fatigue damage during high-frequency switching. The purpose of this mechanism is to incorporate the current operating condition of the unit and long-term mechanical wear into the control criteria, thereby achieving a more complete characterization of the actual available exhaust capacity and reducing the over-utilization of units that appear normal but are actually vulnerable.

[0018] In a preferred embodiment of the present invention, the control center pre-stores the total volume data of the pipeline network; the control center is used to calculate the pressure drop slope based on the pipeline network pressure data; the control center is also used to combine the pressure drop slope and the total volume data of the pipeline network to calculate the compensation gas volume gap.

[0019] This embodiment provides a predictive mechanism for compensating for gas volume shortages. Specifically, in the aforementioned factory station scenario, if the decision to add more units is based solely on the pipeline pressure value at a certain moment, a control delay problem may occur where the response is triggered only after the pressure monitoring value falls below a preset lower limit. For sudden gas consumption scenarios such as stamping lines, welding fixtures, and intermittent purging, what is truly instructive is not a single pressure value, but the rate of pressure drop and the corresponding gas consumption trend under the current total pipeline volume conditions. Specifically, the control center pre-stores the total volume data of the pipeline network, which may include the equivalent volume of the main pipeline, gas storage tank, and main stable cavities after conversion; The control center generates a pressure drop slope based on pipeline pressure data; this slope characterizes the rate of decrease in pipeline pressure per unit time, and essentially reflects the degree to which the downstream gas consumption rate exceeds the upstream gas supply rate. By combining this slope with the total volume of the pipeline network, the control center can transform the originally abstract pressure change trend into a compensation gas volume gap that is more in line with the actual operating needs of the system. In other words, the same pressure drop, if it occurs in a large-volume main pipeline, means that more compressed air is actually lost. If it occurs in a small-volume local branch, its gas replenishment demand is relatively limited; in order to avoid the defects of fuzzy evaluation based solely on empirical coefficients and lacking physical basis, the control center follows gas state deduction with clear physical meaning in this combination process. Because the ambient temperature and gas constant within the station building pipeline system are approximately constant during the short-term drop monitoring window, the pressure drop rate can directly characterize the net loss rate of compressed gas mass within the pipeline network. The control center combines pre-stored total pipeline volume data, the absolute value of the pressure drop slope calculated from pipeline pressure data, and the local standard atmospheric pressure constant to obtain the standard condition volumetric flow rate of the compensation gas volume gap under standard atmospheric pressure through gas state conversion; the specific formula for standard condition gas volume gap conversion is as follows: ; in, To compensate for the gas volume shortfall, standard condition volumetric flow rate This refers to the total volume of the pipeline network. This is the local standard atmospheric pressure constant. The slope of the pressure drop.

[0020] Through this rigorous logical decomposition and calculation, the compensation air volume gap is no longer an abstract trend, but is precisely converted into the exact standard air volume flow requirement that can guide the exhaust distribution of air compressor equipment. For ease of explanation, a simplified comparison example can be used: Assume the station simultaneously monitors two time periods, time period... The pressure in the central pipeline network decreased at the first rate of decline, during the period The pressure in the central pipeline network decreased at a second rate of drop, greater than the first rate of drop, during the period. The absolute value of the rate of change of pressure in the central pipeline network is higher than that of the time period. The total volume of the pipeline network remains unchanged; the control center determines... The corresponding compensation gas volume gap is greater than ; If another station has a larger volume of gas storage tanks and main pipelines under the same pressure descent rate, then the gap represented by its similar slope will also be larger; therefore, the compensation gas volume gap is no longer an empirical estimate, but a physical quantity corresponding to the actual gas storage space. Under abnormal operating conditions, if the total volume of the pipeline changes due to the addition of a gas storage tank, closure of a branch line, or maintenance isolation, the operation and maintenance personnel can update the equivalent total volume through the parameter configuration interface. Before the update is completed, the control center can temporarily use the most recent stable modeling value and indicate on the interface that the current gap prediction accuracy may be reduced. If the pipeline pressure is affected by sensor pulsation, local valve impact or drainage action and an abnormal spike occurs, the control center can first eliminate isolated abnormal points and then identify the real drop trend to avoid mistaking short-term noise for a continuous gas shortage. During the mold change and reset phase in the aforementioned automotive stamping plant, multiple sets of cylinders are simultaneously charged. The pipeline pressure is not only lower than the normal steady-state value, but the absolute value of the pressure drop slope is also greater than the preset cycle drop threshold. Since the station building is equipped with large-capacity gas storage tanks, the control center judged that this decline was not a local transient disturbance, but rather represented that the overall gas storage capacity of the pipeline network was in a state of high pressure differential release. Therefore, a high-level compensation gas volume gap was generated to provide a basis for subsequent unit selection and load allocation. The purpose of this step is to make gas replenishment decisions based on pressure change trends rather than on lag alarms for absolute pressure values, thereby enabling earlier identification of sudden gas consumption events and more accurate prediction of compensation amounts based on actual on-site conditions.

[0021] In a preferred embodiment of the present invention, the air compressor equipment includes a variable frequency air compressor and a fixed frequency air compressor; the equipment control commands include frequency adjustment commands and load signal commands; The control center has a pre-stored load allocation ratio. The control center is used to decompose the compensation air volume gap into basic load and transient fluctuation load according to the load allocation ratio, and allocate the basic load to the air compressor with the highest dynamic effective exhaust contribution index in the target air compressor combination to generate a loading signal command. Then, it selects the variable frequency air compressor with the highest dynamic effective exhaust contribution index from the remaining air compressors and allocates the transient fluctuation load to the variable frequency air compressor to generate a frequency adjustment command.

[0022] This embodiment provides a tiered load allocation mechanism for different unit types; specifically, after the aforementioned station has been running continuously, simply determining which units will participate in gas replenishment is still insufficient to resolve the contradiction between response speed and mechanical losses. If the entire compensation gap is handled by the power frequency generator, it will easily cause frequent loading, unloading and contactor operation; if it is handled by the variable frequency generator, the variable frequency generator will be in a state of large speed regulation for a long time, increasing the heat load and motor impact. Therefore, based on the aforementioned gap prediction, this embodiment further breaks down the compensation gas volume gap into basic load and transient fluctuation load. Specifically, the air compressor equipment in the station includes variable frequency air compressors and fixed frequency air compressors; the control center pre-stores the load distribution ratio, which can be set according to engineering conditions such as the stability of the production line's air consumption, the adjustable range of the variable frequency compressor, and the rated exhaust capacity of the fixed frequency compressor; The basic load corresponds to the continuous gas supply demand with a change rate lower than the preset fluctuation threshold, which is suitable for units with a high dynamic effective exhaust contribution index and stable operation; the transient fluctuating load corresponds to the gas replenishment demand with a change rate greater than or equal to the preset fluctuation threshold, which is more suitable for variable frequency units with a high dynamic effective exhaust contribution index and fast speed regulation response. In terms of execution logic, the control center first selects the unit with the highest dynamic effective exhaust contribution index from the target air compressor combination to undertake the basic load, and then selects the variable frequency unit with the highest dynamic effective exhaust contribution index from the remaining units to undertake the transient fluctuation load. The resulting equipment control commands are differentiated: for power frequency units or stable operating units bearing basic loads, a loading signal command is generated to put them into a continuous gas supply state; for variable frequency units bearing transient fluctuating loads, a frequency adjustment command is generated to make them quickly follow pressure fluctuations within the allowable frequency range. If the current compensation requirement Includes stable components and transient fluctuation load If the first air compressor ranks first in contribution, then the first air compressor shall be responsible for the stabilization part. ; If the third air compressor in the remaining units is a variable frequency unit and has the highest ranking, then the third air compressor will bear the transient load fluctuations. Through the above division of labor, the system allocates the slowly changing base load and the rapidly fluctuating transient load to the execution entities with corresponding physical characteristics, respectively. Under abnormal operating conditions, if there are no available inverters among the remaining units, the control center can convert the transient fluctuating load into a conservative gas supply demand for the online power frequency units, and appropriately trigger the loading in advance to mitigate pressure fluctuations. If the inverter is close to the frequency limit or at the temperature protection boundary, the control center can reduce its transient load ratio and let the next stable unit in the next order take over, so as to prevent the single unit from being in the extreme adjustment state for a long time. If the load circuit of the power frequency unit is temporarily unavailable, the corresponding basic load will be taken over by other available units, and the operation and maintenance interface will indicate that the unit has lost its basic scheduling qualification. In the continuous stamping cycle of the aforementioned automotive stamping plant, the basic air consumption of the production line is relatively stable, while each mold purging and fixture reset will cause short-term peak demand. The control center assigns the primary air consumption to the first air compressor, which currently has the highest dynamic effective exhaust contribution index, while simultaneously assigning these peak fluctuations to the third air compressor, which has a faster response, and absorbing instantaneous disturbances through frequency fine-tuning. This avoids both repeated loading of the second air compressor and the long-term solo air supply task of the third air compressor. The purpose of this mechanism is to enable different models to assume more suitable load roles according to their respective mechanical characteristics, thereby achieving synergy in gas supply stability, execution responsiveness, and equipment life protection.

[0023] In a preferred embodiment of the present invention, the control center pre-stores the slope convergence range; the control center is also used to monitor the convergence state of the pressure drop slope in real time after issuing equipment control commands; the control center is used to maintain the load distribution state of the target air compressor combination when the pressure drop slope converges to the slope convergence range. The control center is also used to trigger a negative feedback mechanism when the pressure drop slope does not converge to the slope convergence range. The negative feedback mechanism includes: reducing the dynamic effective exhaust contribution index of each air compressor in the target air compressor combination, and transferring the load to the next air compressor in the next order of the equipment state matrix in the next calculation cycle.

[0024] This embodiment provides a negative feedback mechanism for closed-loop correction; specifically, under the aforementioned hierarchical load allocation mechanism, the system is already able to allocate basic load and transient fluctuation load to different equipment according to the current state of the unit, but there is still a potential fault in the industrial field: Although a certain unit has completed the loading or frequency increase action under the control command, its actual air replenishment effect has not reached the expected level due to the intake valve sluggishness, increased internal leakage, abnormal cooling or coupling slippage. If the system only relies on the status of the command issuance without verifying whether the pressure drop has truly converged, it will cause misscheduling. Specifically, the control center pre-stores the slope convergence range and continuously monitors the changes in the slope of the pipeline pressure drop after the equipment control command is issued; here, convergence does not mean that the pipeline pressure must immediately rise to a certain fixed value, but rather that the pressure drop trend is significantly weakened until it enters an acceptable stable range. If the slope converges to this range, it means that the load distribution in this round is basically consistent with the actual air supply effect on site. The control center can maintain the load distribution state of the target air compressor combination and avoid unnecessary readjustment. If the slope does not converge, it means that at least the following possibilities exist: the actual exhaust capacity of the selected unit is lower than its current assessment result, the downstream gas consumption impact exceeds the prediction of this round, and a certain unit is under control but the gas supply delay is obvious. To this end, this embodiment introduces a negative feedback mechanism, that is, in the next calculation cycle, the dynamic effective exhaust contribution index of the relevant units in the current target air compressor combination is reduced, so that its ranking in the equipment state matrix is ​​moved to the back, and the load is transferred to the next priority unit. This can be illustrated with a logical example: If the initial order is first air compressor, third air compressor, second air compressor, and fourth air compressor, and the pressure drop continues after the first and third air compressors are called in this round, then in the next cycle, the order of the first or third air compressor can be reduced to after the second air compressor, so that the second air compressor can take over part of the load. In this way, the system does not unconditionally continue to call the same unit that is theoretically effective but has limited actual output, but corrects its judgment based on the closed-loop results. In the anomaly handling mechanism, if the pressure drop slope does not converge, but at the same time a significant new gas consumption event is detected downstream, such as the entire stamping line being reset simultaneously, the control center can first determine that the external load is changing rapidly, rather than immediately treating all the units in operation as failure objects. At this time, a weight reduction strategy with a preset low-order step size can be adopted. Specifically, the reduction method is to multiply the current dynamic effective exhaust contribution index of the target air compressor by a preset attenuation coefficient less than 1, or subtract a preset fixed value step size; to avoid intervention deviation of healthy units caused by external transient disturbances; if communication delay causes the execution confirmation signal to not be returned in time, the control center can set a short waiting window and evaluate the slope convergence status after confirming that the equipment has completed the action. If there is still no convergence trend after multiple negative feedbacks, it should be upgraded to an abnormal operating condition and, if necessary, switch to a higher level of safe gas supply mode. During the second production shift of the aforementioned factory, after the third air compressor received the frequency increase command, its frequency converter feedback showed that it had reached the target frequency, but the pipeline pressure continued to drop rapidly. Based on the changes in exhaust temperature and power, the control center deduced that the third air compressor may have a hidden internal leak or an obstructed intake passage. Therefore, in the next cycle, the contribution ranking of the third air compressor was downgraded, some of the fluctuating load was transferred to the second or fourth air compressor, and the third air compressor was kept in a lower priority position for continued observation. The purpose of this mechanism is to form a closed-loop control link of instruction issuance, result verification, and sorting correction, so as to realize dynamic correction of deviations in the actual gas supply capacity of the unit and avoid the long-term solidification of high-priority errors.

[0025] In a preferred embodiment of the present invention, the control center has an extreme drop threshold pre-stored; a bypass hard-wired circuit is also provided between the execution control module and the air compressor equipment; the control center is used to generate equipment control commands by using a preset equipment state matrix and target air compressor combination when the absolute value of the pressure drop slope is less than or equal to the extreme drop threshold. The control center is also used to activate the hard-wired cascaded full-open mode based on the bypass hard-wired circuit when the absolute value of the pressure drop slope is greater than the extreme drop threshold, forcing all online air compressors to run at full load.

[0026] This embodiment provides a redundant safety protection mechanism under extreme operating conditions; specifically, the aforementioned implementation methods are all based on the premise that there is time to perform state assessment and load optimization, and are applicable to most normal fluctuation scenarios. However, extreme events may still occur in industrial settings, such as main pipeline rupture, critical branch flange detachment, accidental opening of large-diameter drain valves, or downstream accident interlocking causing multiple high-flow actuators to simultaneously bleed out uncontrollably. At this time, the pipeline pressure will drop sharply at a rate far exceeding normal fluctuations. If we still insist on sorting, evaluating and optimizing the allocation according to the usual method, we will miss the opportunity to maintain pressure due to the natural delay in the calculation and execution cycle. Specifically, the control center pre-stores an extreme drop threshold, which is used to distinguish between normal supply and demand imbalance and accident-level pressure loss trend. When the absolute value of the pressure drop slope is within the threshold, the system continues to use the equipment state matrix and target air compressor combination to generate equipment control commands. At this time, the optimization objectives still include efficiency, fatigue and temperature rise balance. When the absolute value of the pressure drop slope exceeds the threshold, the control center immediately determines that it has entered an extreme pressure loss state and switches to the bypass hard-wired circuit to trigger the hard-wired cascaded full-open mode. The so-called bypass hard-wired circuit is a direct electrical forced channel relative to the conventional communication control link. Its advantages are that the logical path is short, the resistance to software failure is strong, and it can directly issue a full-load operation command to all online air compressors in case of an accident. From an industrial perspective, during an accident-level pressure loss phase, the primary goal of the system is no longer which unit has the lowest energy consumption and the least mechanical fatigue loss, but rather to integrate all available compression capacity into the main pipeline with the highest priority. At this point, allowing all online air compressors to operate at full load can delay the rate at which the pipeline pressure drops to the preset dangerous lower limit, buying time for downstream emergency shutdowns, isolation of faulty branches, or manual intervention. This mode is equivalent to degrading optimized control to safety control; it is a functional degradation with clear boundaries, rather than uncontrolled operation. In the fault-tolerant control mechanism, if the control center detects an extremely rapid pressure drop, but at the same time the pressure sensor self-diagnoses abnormally, the system can adopt a dual-condition confirmation method of sensor abnormality and low-pressure switch triggering of the main pipeline to avoid unnecessary full load of the entire station due to false alarm of a single sensor. If some units are in maintenance isolation or thermal protection lockout, the hard-wired cascade full-on mode only applies to online units that are allowed to be put into operation, and does not forcibly remove the hardware protection of the equipment itself. If the pressure drop slope returns to within the threshold after the extreme pressure loss is relieved, the system should not immediately and frequently switch back to the optimization mode. Instead, a recovery confirmation phase should be set up, and the system should gradually exit the cascaded full-open state after the pressure trend stabilizes. After the aforementioned automobile factory's weekend maintenance switchover, a flange on a certain main branch line was not fully tightened. After the gas supply was restored, a release exceeding the preset flow threshold occurred, and the pipeline pressure decreased at a rate greater than the preset limit drop threshold within the preset time window. The control center recognized that the drop speed was significantly higher than the normal characteristics of mold changing or purging air usage. Therefore, it immediately bypassed the conventional sequencing logic and forced the four online units of the first, second, third and fourth air compressors to run at full load by using a bypass hard-wired circuit. At the same time, it issued an extreme pressure loss alarm to the upper-level monitoring to ensure that the main pipeline network maintained the minimum acceptable pressure before the fault was isolated. The purpose of this mechanism is to establish clear safety boundaries for optimized control, prioritizing pressure maintenance safety in catastrophic pressure loss scenarios, thereby achieving the certainty and system safety margin required in industrial settings.

[0027] In a preferred embodiment of the present invention, the control center further includes a historical database and pre-stores attenuation thresholds. The control center is used to continuously store the dynamic effective exhaust contribution index of each air compressor into the historical database to generate historical attenuation curves. The control center is also used to predict equipment status based on the historical attenuation curves, extract the attenuation rate of the historical attenuation curves within a preset observation window, and determine abnormal attenuation and generate equipment maintenance warning instructions when the absolute value of the attenuation rate of the historical attenuation curve is greater than the attenuation threshold. When the absolute value of the attenuation rate of the historical attenuation curve is less than or equal to the attenuation threshold, it is determined to be normal attenuation and the current operating state is maintained.

[0028] This embodiment provides a state tracking mechanism for predictive maintenance. Specifically, after the aforementioned station has been running continuously for a period of time, scheduling can be carried out solely based on the dynamic effective exhaust contribution index at the current moment, which can solve the real-time gas supply problem, but is still insufficient to reveal the long-term trend of continuous performance degradation of a certain unit. In industrial settings, faults such as rotor wear, oil circuit contamination, cooler blockage, and increased bearing friction often do not occur suddenly, but rather manifest as a slow decay over a long period. If the system can save the contribution index used in each scheduling operation for a long time, the evolution of the mechanical state can be observed in reverse from the control data. Specifically, the control center includes a historical database, which continuously stores the dynamic effective exhaust contribution index of each unit under different shifts and different load periods, and forms the corresponding historical decay curves; these curves are not limited to graphical displays, but are essentially state trajectories arranged in chronological order. If a unit maintains a stable contribution level under similar production loads for a long period of time, it indicates that its effective exhaust capacity is relatively stable; if the contribution level of the unit continues to decline without significant changes in process load, it may mean that the volumetric efficiency, heat dissipation capacity or mechanical reliability is declining. The control center predicts equipment status based on this; when the decay rate of the historical decay curve exceeds the pre-stored decay threshold, the system determines it as abnormal decay and generates an equipment maintenance warning command; in order to accurately capture the real degradation trend and filter the data noise caused by daily operating condition fluctuations, the control center does not use adjacent extreme values ​​in a short period of time for simple difference calculation, but adopts sliding time window logic for structured prediction. Specifically, the system sets a preset observation window, performs least squares fitting on the data points of the historical decay curve within the window, and extracts the falling slope of the fitted line as the current decay rate. Only when the absolute value of the decay rate is greater than the decay threshold, and this monotonically decreasing trend continues steadily in multiple consecutive sliding windows, does the control center determine that irreversible real performance degradation has occurred, and then generate equipment maintenance warning instructions. The early warning here is not a single-dimensional threshold exceeding alarm, but rather a combination of the unit's long-term trend and comparison with other units in the station to identify degradation patterns that do not conform to normal aging patterns. Taking a simplified engineering scenario as an example: if the first, second, and third air compressors all decrease at the first decay rate within the same month, while the fourth air compressor decreases at the second decay rate, which is greater than the first decay rate, under the same production cycle, then the system will mark the fourth air compressor as an abnormal decay object; maintenance personnel can then prioritize checking the cooler, intake valve, oil separator system, or rotor wear of the fourth air compressor. In the fault-tolerant control mechanism, if a unit has just completed a major overhaul, oil change, or cooling system cleaning, its contribution index curve may show a phased rebound. The control center can write the maintenance time point into the historical database as a reference for interpreting subsequent trends. If the factory's production load changes significantly within a certain statistical period, such as the addition of a high-gas-consuming workstation or a long-term shutdown, the system should refer to the load background of the same period when generating attenuation judgments to avoid misjudging the overall fluctuations caused by changes in operating conditions as single-machine failures. If there are gaps in historical data, the control center can first extend the observation period and make abnormal attenuation judgments after the data continuity is restored. During the three consecutive weeks of production at the aforementioned automobile factory, although the second air compressor was able to participate in daily air replenishment, its dynamic effective exhaust contribution index continued to decline under similar shifts and similar pipeline pressure conditions, and the rate of decline was significantly faster than that of the first and third air compressors. The control center generates maintenance warnings, prompting maintenance personnel to prioritize checking for scaling on the second air compressor cooler and sluggish intake valve operation when the line is shut down on weekends. In actual maintenance, potential faults can be detected in advance, thus preventing the second air compressor from suddenly failing during subsequent full-load production. The purpose of this mechanism is to further transform the state variables generated during real-time linkage control into long-term data that can be used for maintenance decisions, thereby achieving integrated connection between gas supply control and equipment early warning and reducing the risk of sudden shutdowns.

[0029] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A multi-channel air compressor linkage control system with balanced exhaust volume and load, used to control air compressor equipment and pipeline equipment composed of multiple air compressors, characterized in that, include: The status acquisition module is communicatively connected to the air compressor equipment and the pipeline network equipment, respectively, and is used to collect the operating status data of each air compressor and the pipeline pressure data of the pipeline network equipment. The operating status data includes instantaneous active power and exhaust temperature; An execution control module is communicatively connected to the air compressor equipment and is used to control the operating status of the air compressor equipment; The control center is communicatively connected to the status acquisition module and the execution control module, respectively. It has pre-stored the rated parameters of the air compressor and is used to process the operating status data and the pipeline pressure data to generate equipment control commands. The equipment control commands are then sent to the execution control module for load balancing management of the exhaust volume. The control center is used to: calculate the real-time exhaust volume of each air compressor based on the operating status data and the rated parameters of the air compressor; The dynamic effective exhaust contribution index of each air compressor is evaluated based on the operating status data; the compensation air volume gap is predicted based on the pipeline pressure data. Based on the dynamic effective exhaust contribution index of each air compressor, an equipment state matrix is ​​constructed, and target air compressor combinations are selected in the equipment state matrix in descending order of the dynamic effective exhaust contribution index until the total real-time exhaust volume of the target air compressor combinations is greater than or equal to the compensation air volume gap. Based on the target air compressor combinations, the equipment control command is generated.

2. The multi-channel air compressor linkage control system with balanced exhaust volume and load according to claim 1, characterized in that, The operating status data also includes the cumulative number of loading cycles; the control center is used to calculate the power-time change rate based on the instantaneous active power and the temperature increment rate based on the exhaust temperature; the control center has preset weights corresponding to the power-time change rate, the temperature increment rate and the cumulative number of loading cycles respectively.

3. The multi-channel air compressor linkage control system with balanced exhaust volume and load according to claim 1, characterized in that, The control center has pre-stored the total volume data of the pipeline network; The control center is used to calculate the pressure drop slope based on the pipeline pressure data; The control center is also used to calculate the compensation gas volume gap by combining the pressure drop slope and the total volume data of the pipeline network.

4. The multi-channel air compressor linkage control system with balanced exhaust volume and load according to claim 3, characterized in that, The air compressor equipment includes a variable frequency air compressor and a fixed frequency air compressor; the equipment control commands include frequency adjustment commands and load signal commands; the control center pre-stores load distribution ratios; The control center is used to decompose the compensation air volume gap into a basic load and a transient fluctuation load according to the load allocation ratio, and to allocate the basic load to the air compressor with the highest dynamic effective exhaust contribution index in the target air compressor combination to generate the loading signal command. Then, it selects the variable frequency air compressor with the highest dynamic effective exhaust contribution index from the remaining air compressors and allocates the transient fluctuation load to the variable frequency air compressor to generate the frequency adjustment command.

5. The multi-channel air compressor linkage control system with balanced exhaust volume and load according to claim 4, characterized in that, The control center has a pre-stored slope convergence range; the control center is also used to monitor the convergence status of the pressure drop slope in real time after issuing the equipment control command; The control center is used to maintain the load distribution state of the target air compressor assembly when the pressure drop slope converges to the slope convergence range; The control center is also used to trigger a negative feedback mechanism when the pressure drop slope does not converge to the slope convergence range; the negative feedback mechanism includes: reducing the dynamic effective exhaust contribution index of each air compressor in the target air compressor combination, and transferring the load to the next air compressor in the next order of the equipment state matrix in the next calculation cycle.

6. The multi-channel air compressor linkage control system with balanced exhaust volume and load according to claim 3, characterized in that, The control center has a pre-stored extreme drop threshold; a bypass hard-wired circuit is also provided between the execution control module and the air compressor equipment; The control center is used to generate the equipment control command by combining the equipment state matrix and the target air compressor when the absolute value of the pressure drop slope is less than or equal to the extreme drop threshold. The control center is also used to enable the hard-wired cascaded full-open mode based on the bypass hard-wired circuit when the absolute value of the pressure drop slope is greater than the extreme drop threshold, forcing all online air compressors to run at full load.

7. The multi-channel air compressor linkage control system with balanced exhaust volume and load according to claim 2, characterized in that, The control center also includes a historical database and pre-stores attenuation thresholds; The control center is used to continuously store the dynamic effective exhaust contribution index of each air compressor into the historical database to generate historical decay curves. The control center is also used to predict the equipment status based on the historical attenuation curve, extract the attenuation rate of the historical attenuation curve within a preset observation window, and determine abnormal attenuation and generate equipment maintenance warning instructions when the absolute value of the attenuation rate of the historical attenuation curve is greater than the attenuation threshold; and determine normal attenuation and maintain the current operating state when the absolute value of the attenuation rate of the historical attenuation curve is less than or equal to the attenuation threshold.

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