Coordinated scheduling method for bulk and general cargo port berth and yard facing unloading operation

Abstract

The application discloses a kind of bulk cargo wharf and yard collaborative scheduling method for unloading operation, belong to bulk cargo port scheduling technical field.Currently, the linkage of unloading, belt conveying and yard material taking operation in bulk cargo port unloading operation is poor, and problems such as multi-type congestion are prone to occur, and there are scheduling lag, low operation efficiency defects.The first difference and the second difference are calculated by collecting unloading flow, conveying flow, real-time material level and other operation data, a variety of operation conditions are divided in combination with the two types of difference, real-time material level and yard remaining capacity, and scheduling operations such as overall congestion relief, local congestion relief, yard side relief, material supply compensation and composite state classification collaboration are executed in a targeted manner, and the equipment parameters are stable in abnormal working condition.The application can realize the dynamic collaborative scheduling of port berth and yard equipment, effectively avoid operation congestion and material supply abnormal problems, and is suitable for intelligent scheduling scenarios of various bulk cargo port unloading operations.

Description

Technical Field

[0001] This invention relates to the field of bulk cargo port scheduling technology. More specifically, this invention relates to a method for coordinated scheduling of bulk cargo port berths and storage yards for unloading operations. Background Technology

[0002] Bulk cargo port unloading operations consist of a continuous operational chain comprised of unloaders, main conveyors, stackers, and yard capacity systems. Flow matching and status coordination among these devices are crucial for ensuring stable unloading operations. Existing bulk cargo port unloading scheduling methods often employ fixed-parameter operation and segmented independent control, managing only the operating status of individual devices without establishing a coordinated monitoring and joint judgment mechanism for unloading flow, conveying flow, yard stockpiling flow, material level, and remaining yard capacity. This results in several inherent technical deficiencies in the existing scheduling system.

[0003] Existing technologies cannot comprehensively assess multi-level flow differences, buffer levels, and remaining yard capacity within the operational chain, nor can they distinguish the specific types of operational anomalies. Current scheduling methods struggle to differentiate between various congestion conditions, such as overall system congestion, localized congestion between the unloader and conveyor belt, and localized congestion between the conveyor belt and the yard side. They also cannot distinguish whether the congestion is caused by equipment flow mismatch or a full yard, leading to ineffective and untargeted control measures. Furthermore, existing technologies lack adaptive control logic for single conditions like insufficient unloading material supply or complex conditions involving insufficient supply combined with tight yard storage. They cannot differentiate control based on the remaining yard capacity, easily resulting in operational idling due to insufficient supply or operational disorder under complex conditions.

[0004] Meanwhile, traditional scheduling modes, employing fixed thresholds and speed parameters, cannot dynamically adapt control standards based on real-time material levels and remaining yard capacity, making them ill-suited for the dynamic fluctuations in unloading operations. Existing technologies lack refined and tiered handling logic when facing scenarios such as near-full yards, abnormally high material levels, and dynamic imbalances in flow rates, failing to effectively balance equipment congestion relief, material supply compensation, and full-yard protection. These specific problems with existing technologies result in poor stability of the port unloading operation chain, low equipment matching accuracy, and delayed handling of abnormal conditions, limiting overall unloading efficiency and failing to meet the continuous, stable, and high-precision collaborative scheduling requirements of bulk cargo ports. Summary of the Invention

[0005] Another objective of this invention is to provide a collaborative scheduling method for bulk cargo port berths and storage yards for unloading operations. Existing port unloading equipment has fixed operating parameters and lacks a comprehensive evaluation method based on multi-dimensional flow, material level, and storage capacity data. It is difficult to accurately distinguish between overall congestion, two types of local congestion, insufficient material supply, and compound anomalies. It is impossible to select corresponding handling measures according to the actual situation on site. Abnormal operating conditions can only maintain the original operating state, and it is difficult to deal with the problem of link flow imbalance in a timely manner, making it difficult to guarantee the stability of operation.

[0006] Traditional scheduling methods cannot accurately collect flow data at each stage of unloading, conveying, and stockpiling. There is a lack of standardized ways to obtain the remaining capacity of the stockpile and the level of the buffer hopper. The channels for collecting core operating parameters are not clear enough, which cannot provide real and effective data support for condition judgment and scheduling control, directly affecting the accuracy of scheduling judgment results.

[0007] The existing dispatching system did not set up differentiated handling plans for various congestion, overcapacity, and insufficient supply scenarios. Under abnormal operating conditions, the equipment adjustment mode was singular and fixed, and it could not flexibly adjust the operation strategy according to the remaining storage capacity of the yard. This easily led to situations where the handling method did not match the actual operating conditions, and the congestion relief and storage capacity protection effects did not meet the operational requirements.

[0008] When faced with a combination of insufficient material supply and tight storage capacity, there is no hierarchical handling logic, and it is impossible to classify the control level based on the remaining capacity of the storage yard. After the operation is restored, there is also a lack of supporting follow-up control methods, which can easily cause repeated fluctuations in the operation status and make it difficult to smoothly eliminate the abnormal problems of the combined operation.

[0009] Conventional scheduling uses fixed judgment thresholds, which cannot adjust the evaluation criteria in real time based on the level of buffer material and the remaining capacity of the stockpile. The threshold parameters are poorly adapted to dynamically changing operating conditions, the operating condition judgment criteria are rigid, which can easily lead to judgment bias and reduce the rationality of scheduling decisions.

[0010] In the past, the method of setting the speed adjustment range of equipment was simple and crude. It did not take into account the actual state of flow difference, material level and silo capacity to calculate the adjustment amount, nor did it use mature control algorithms to calculate operating parameters. The speed adjustment range and the degree of imbalance on site were not well matched, which easily led to over-adjustment or under-adjustment, and it was impossible to smoothly correct the flow deviation.

[0011] The operation control does not cover the material stacking process at the yard entrance, making it impossible to identify congestion caused by insufficient operation capacity of the stacking equipment. There is a lack of corresponding flow difference judgment basis, making it difficult to detect abnormalities in the stacking process in the first place. The stacking jam problem will continue to have an adverse impact on the entire material conveying operation process.

[0012] When insufficient stockpiling capacity causes congestion, the lack of tiered handling based on the storage capacity of the stockpiles and the availability of idle stockpiles in the yard, the absence of standardized stockpile replacement and flow coordination management models, and the limited means of handling stockpiles when they are full, make it impossible to make full use of the storage space in the yard and easily trigger full-warehouse shutdown control.

[0013] During the stacker crane's cross-stacking and silo relocation operation, the safe operating flow rate was not determined by combining the hopper's storage capacity with the equipment's relocation time. During the silo relocation, the material conveying control order was chaotic, which easily led to material accumulation or shortage. After the silo relocation was completed, it was difficult to smoothly restore the original operating state.

[0014] To achieve these objectives and other advantages according to the present invention, a method for coordinated scheduling of bulk cargo port berths and yards for unloading operations is provided, comprising the following steps: The instantaneous unloading flow rate of the ship unloader, the instantaneous conveying flow rate of the main conveyor belt, the instantaneous stacking flow rate of each stacker, the remaining capacity of each stockpile in the yard, and the real-time material level are obtained and transmitted to the controller. The controller sums the instantaneous stockpiling flow rates of each stacker to obtain the instantaneous total stockpiling flow rate of the stockyard; it calculates the difference between the instantaneous unloading flow rate and the instantaneous conveying flow rate, and records it as the first difference; it calculates the difference between the instantaneous conveying flow rate and the instantaneous total stockpiling flow rate of the stockyard, and records it as the second difference; and based on the first difference, the second difference, and the real-time material level, it makes the following judgments: When the first difference is greater than the first preset positive threshold, the second difference is greater than the second preset positive threshold, and the real-time material level is higher than the preset high material level threshold for a duration exceeding the preset time threshold, the remaining capacity is further detected: if the remaining capacity is not lower than the preset low capacity threshold, the controller determines that there is overall congestion and performs overall congestion relief operation; if the remaining capacity is lower than the preset low capacity threshold, the controller determines that the system congestion is caused by the yard being close to full capacity and performs yard full capacity processing. When the first difference is greater than the first preset positive threshold, the second difference is not greater than the second preset positive threshold, and the real-time material level is higher than the preset high material level threshold and the duration exceeds the preset time threshold, it is judged as a local congestion between the ship unloader and the main conveyor belt, and a local congestion relief operation is performed. When the first difference is not greater than the first preset positive threshold and not less than the first preset negative threshold, and the second difference is greater than the second preset positive threshold and the duration exceeds the preset time threshold, it is determined that there is a local congestion between the main conveyor belt and the stockyard, and a stockyard-side decongestion operation is performed. When the first difference is less than the first preset negative threshold, the second difference is not greater than the second preset positive threshold, the remaining capacity is not lower than the preset low capacity threshold, and the duration exceeds the preset time threshold, the controller determines that the unloader is not supplying enough material and the system is not congested as a whole, and performs a material supply compensation operation. When the first difference is less than the first preset negative threshold and the second difference is greater than the second preset positive threshold and the duration exceeds the preset time threshold, it is judged to be a complex state of insufficient material supply from the ship unloader accompanied by tight storage capacity in the yard, and a complex state hierarchical collaborative operation is executed; In the case where it does not fall into any of the above states, the controller maintains the current operating parameters of each device unchanged and continues to monitor. The controller dynamically adjusts the first preset positive threshold based on the real-time material level: the higher the real-time material level, the lower the first preset positive threshold; the lower the real-time material level, the higher the first preset positive threshold. The controller also dynamically adjusts the second preset positive threshold based on the remaining capacity: the higher the remaining capacity, the higher the second preset positive threshold; the lower the remaining capacity, the lower the second preset positive threshold.

[0015] Preferably, the instantaneous unloading flow rate of the ship unloader is obtained by a first flow sensor installed on the ship unloader; the instantaneous conveying flow rate of the main conveyor belt is obtained by a second flow sensor installed on the main conveyor belt connecting the berth and the stockyard; the instantaneous stacking flow rate of each stacker is obtained by a third flow sensor installed on each stacker in the stockyard; the remaining capacity of each stockpile in the stockyard is obtained by using an inventory detection unit installed in the stockyard; and the real-time material level is obtained by using a buffer hopper installed between the ship unloader and the main conveyor belt, with a material level sensor installed in the buffer hopper.

[0016] Preferably, the overall congestion relief operation specifically involves: sending a speed reduction command to the ship unloader to reduce the instantaneous unloading flow, and simultaneously sending a reinforcement command to the yard dispatch system to increase the number of standby stackers; the yard full handling operation specifically involves: sending a speed reduction command to the ship unloader, or sending a speed reduction command to the main conveyor belt, or sending a speed reduction command to both simultaneously, issuing an early warning message that the yard is approaching full capacity, without adding standby stackers; the material supply compensation operation specifically involves: sending a speed increase command to the ship unloader to increase the instantaneous unloading flow; The specific operation for relieving local congestion is as follows: send a speed reduction command to the ship unloader to reduce the instantaneous unloading flow rate; the specific operation for relieving congestion on the stockyard side is as follows: first, detect the remaining capacity. If the remaining capacity is not lower than the preset low capacity threshold, the controller sends an acceleration command to at least one stacker to increase the instantaneous stacking flow rate; if the remaining capacity is lower than the preset low capacity threshold, the controller determines that the stockyard is close to full and sends a speed reduction command to the ship unloader, or to the main conveyor belt, or to both simultaneously, to reduce the instantaneous conveying flow rate, and at the same time issues a warning message that the stockyard is close to full.

[0017] Preferably, the composite state hierarchical cooperative operation specifically includes: First, the remaining capacity is checked. If the remaining capacity is not lower than the preset low capacity threshold, it is determined that the yard still has the capacity to accept, and the controller sends an acceleration command to the stacker. If the remaining capacity is lower than the preset low capacity threshold, it is determined that the yard is close to saturation, and the controller sends a deceleration command or a pause command to the unloader, while sending a deceleration command to the main conveyor belt and issuing a yard full alarm. After completing the above operations, if the second difference has recovered to no greater than the second preset positive threshold, and the first difference is still less than the first preset negative threshold, and the remaining capacity is not lower than the preset low capacity threshold, then the controller performs a material supply compensation operation; if the remaining capacity is still lower than the preset low capacity threshold, then the controller maintains the current deceleration or pause state and continues to monitor until the remaining capacity recovers to no less than the preset low capacity threshold before performing the material supply compensation operation.

[0018] Preferably, the magnitude of the deceleration or acceleration command is a continuously adjustable value, calculated in real time by the controller based on the first difference, real-time material level, and remaining capacity using a proportional-integral-derivative control algorithm or a model predictive control algorithm. Specifically, the magnitude of the deceleration command satisfies the following: the larger the absolute value of the first difference, the larger the deceleration magnitude; and the higher the real-time material level or the lower the remaining capacity, the larger the deceleration magnitude. The magnitude of the acceleration command satisfies the following: the larger the absolute value of the first difference, the larger the acceleration magnitude.

[0019] Preferably, multiple stackers are installed at the end of the main conveyor belt and at the entrance of the stockyard. Each stacker is equipped with a third flow sensor to acquire the instantaneous stacking flow rate of a single stacker. The controller also calculates the difference between the instantaneous conveyor flow rate and the sum of the instantaneous stacking flows of all stackers, which is recorded as the third difference, and monitors the operating status of each stacker. When the third difference is greater than a third preset positive threshold and the duration exceeds a preset time threshold, the controller determines that the congestion is caused by insufficient stacking capacity. If the current instantaneous stacking flow rate of at least one operating stacker does not reach its rated capacity, an acceleration command is sent to at least one stacker that has not reached its rated capacity. If the current instantaneous stacking flow rate of all operating stackers has reached its rated capacity, a standby stacker is started.

[0020] Preferably, after determining that the congestion is caused by insufficient stacking capacity, the controller first obtains the remaining capacity of all currently operating stack positions; If the remaining capacity is not lower than the preset low capacity threshold, then the operation of sending an acceleration command to the stacker or starting the standby stacker will be executed. If the remaining capacity is lower than the preset low capacity threshold, the controller further checks whether there are other vacant stacks in the yard with a remaining capacity not lower than the preset low capacity threshold. If there are vacant stacks, the controller sends a transfer command to the yard scheduling system, controls one of the stackers to move to the vacant stack, and reduces the instantaneous conveying flow of the main conveyor belt to zero during the transfer. After the stacker is in place at the vacant stack, the instantaneous conveying flow of the main conveyor belt is restored to the value before the reduction. If there are no vacant stacks, the controller determines that the yard is full and does not perform the transfer operation. Instead, it performs yard full handling, that is, it sends a speed reduction command to the unloader, or a speed reduction command to the main conveyor belt, or simultaneously sends a speed reduction command to both the unloader and the main conveyor belt, and issues a warning message that the yard is close to full.

[0021] Preferably, the specific method for the position transfer operation is as follows: The controller obtains the real-time material level of the buffer hopper and calculates the current remaining available volume of the buffer hopper; at the same time, it obtains the estimated movement time required for the stacker to move from the current stack position to the target empty stack position. The controller calculates a safe flow rate value for the unloader based on the remaining available volume and the estimated travel time. This safe flow rate value is equal to the quotient obtained by multiplying the remaining available volume by the material bulk density and then dividing by the estimated travel time. The material bulk density is preset according to the current type of cargo being unloaded. During the transfer operation, the controller sends a speed reduction command to the unloader, reducing the instantaneous unloading flow rate of the unloader to no more than the safe flow rate value of the unloader; at the same time, the controller sends a stop command to the main conveyor belt, reducing the instantaneous conveying flow rate of the main conveyor belt to zero; at the same time, it monitors the real-time material level of the buffer hopper, and stops the unloader immediately when the material level reaches the preset maximum material level. After the stacker is in place in an empty stacking position and the stacker arm is aligned, the controller first starts the main conveyor belt. After the main conveyor belt runs stably, the instantaneous unloading flow of the unloader is gradually restored to the value before the transfer operation. Then the first difference and the second difference are recalculated, and the status is judged based on the real-time material level and remaining capacity.

[0022] The present invention has at least the following beneficial effects: This invention collects multiple real-time operational data for numerical calculations, and combines the calculation results with material level and storage capacity to classify various operating conditions, enabling accurate identification of various abnormal operating states. It can match corresponding scheduling and handling actions according to preset rules, stably maintain equipment operating parameters when there are no abnormal conditions, effectively distinguish the causes of abnormalities, and specifically improve flow imbalances, thereby enhancing the smoothness of the entire unloading process.

[0023] This invention utilizes corresponding sensors and detection units to collect flow rate, material level, and stockpile capacity data at each stage, clearly defining the standardized acquisition path for key parameters. It can reliably acquire operational information closely aligned with the actual site conditions, providing a solid data foundation for condition assessment, numerical calculations, and the issuance of scheduling commands, ensuring that scheduling decisions align with real-world operational scenarios.

[0024] This invention sets up specific handling measures for different abnormal operating conditions, and flexibly switches the control mode based on the remaining capacity of the storage yard. It can reasonably adjust the operating status of unloading, conveying, and stacking equipment according to the type of congestion and storage capacity, and orderly complete the work of congestion relief, full storage warning and material replenishment, so that the handling method is adapted to the on-site operating conditions and the duration of abnormal problems is shortened.

[0025] This invention adopts a tiered handling model for complex operational anomalies, selecting different control measures based on the storage yard capacity, and simultaneously carrying out material supply compensation operations once the operating conditions improve. This can gradually resolve multiple overlapping operational problems, reduce frequent fluctuations in operational status, smoothly restore the normal material supply and storage rhythm, and reduce the negative impact of complex faults on unloading efficiency.

[0026] This invention dynamically adjusts the judgment threshold based on real-time material level and remaining capacity in the stockpile, ensuring that the evaluation criteria change synchronously with on-site operating conditions. This effectively reduces the probability of operational condition judgment deviations, allows the judgment rules to adapt to real-time changes in material conveying and storage, and further improves the accuracy of identifying various operational states.

[0027] This invention employs a professional control algorithm combined with multiple field parameters to calculate the speed adjustment range, ensuring that the adjustment magnitude is adapted to the degree of flow imbalance and the current material level and storage capacity. This achieves continuous and stable adjustment of equipment speed, avoiding operational fluctuations caused by unreasonable adjustments, gradually correcting flow differences between various devices, and bringing the material conveying ratio back to a reasonable range.

[0028] This invention adds a material stacking flow monitoring and difference judgment step, which can promptly detect congestion problems caused by insufficient material stacking capacity. It can quickly issue control commands in response to material stacking anomalies, mobilize equipment operating capacity to fill the material stacking gap, eliminate the obstruction caused by material stacking blockage, and ensure that materials are smoothly delivered to the stockpile for storage.

[0029] This invention combines single-staple storage capacity with the utilization of idle storage space within the yard to address stockpiling congestion in a tiered manner, and rationally implements stacking location switching and flow control. It fully utilizes existing storage space in the yard, reduces unnecessary full-store shutdowns, and solves stockpiling congestion problems while maximizing the actual carrying capacity of the yard.

[0030] This invention combines the available hopper volume with the estimated equipment relocation time to calculate safe operating flow, standardizing the material conveying control process throughout the entire warehouse relocation process. It effectively avoids problems such as material accumulation and material shortages during warehouse relocation, ensuring the safe conduct of equipment relocation operations. After the equipment is in place, the original operating parameters can be smoothly restored, maintaining the continuous operation of the workflow.

[0031] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Detailed Implementation

[0032] The present invention will be further described in detail below with reference to embodiments, so that those skilled in the art can implement it based on the description.

[0033] This invention provides a method for coordinated scheduling of bulk cargo port berths and storage yards for unloading operations, comprising the following steps: The instantaneous unloading flow rate of the ship unloader, the instantaneous conveying flow rate of the main conveyor belt, the instantaneous stacking flow rate of each stacker, the remaining capacity of each stockpile in the yard, and the real-time material level are obtained and transmitted to the controller. The controller sums the instantaneous stockpiling flow rates of each stacker to obtain the instantaneous total stockpiling flow rate of the stockyard; it calculates the difference between the instantaneous unloading flow rate and the instantaneous conveying flow rate, and records it as the first difference; it calculates the difference between the instantaneous conveying flow rate and the instantaneous total stockpiling flow rate of the stockyard, and records it as the second difference; and based on the first difference, the second difference, and the real-time material level, it makes the following judgments: When the first difference is greater than the first preset positive threshold, the second difference is greater than the second preset positive threshold, and the real-time material level is higher than the preset high material level threshold for a duration exceeding the preset time threshold, the remaining capacity is further detected: if the remaining capacity is not lower than the preset low capacity threshold, the controller determines that there is overall congestion and performs overall congestion relief operation; if the remaining capacity is lower than the preset low capacity threshold, the controller determines that the system congestion is caused by the yard being close to full capacity and performs yard full capacity processing. When the first difference is greater than the first preset positive threshold, the second difference is not greater than the second preset positive threshold, and the real-time material level is higher than the preset high material level threshold and the duration exceeds the preset time threshold, it is judged as a local congestion between the ship unloader and the main conveyor belt, and a local congestion relief operation is performed. When the first difference is not greater than the first preset positive threshold and not less than the first preset negative threshold, and the second difference is greater than the second preset positive threshold and the duration exceeds the preset time threshold, it is determined that there is a local congestion between the main conveyor belt and the stockyard, and a stockyard-side decongestion operation is performed. When the first difference is less than the first preset negative threshold, the second difference is not greater than the second preset positive threshold, the remaining capacity is not lower than the preset low capacity threshold, and the duration exceeds the preset time threshold, the controller determines that the unloader is not supplying enough material and the system is not congested as a whole, and performs a material supply compensation operation. When the first difference is less than the first preset negative threshold and the second difference is greater than the second preset positive threshold and the duration exceeds the preset time threshold, it is judged to be a composite state of insufficient material supply from the unloader accompanied by tight storage capacity in the yard, and a composite state hierarchical collaborative operation is executed; In the case where it does not fall into any of the above states, the controller maintains the current operating parameters of each device unchanged and continues to monitor. The controller dynamically adjusts the first preset positive threshold based on the real-time material level: the higher the real-time material level, the lower the first preset positive threshold; the lower the real-time material level, the higher the first preset positive threshold. The controller also dynamically adjusts the second preset positive threshold based on the remaining capacity: the larger the remaining capacity, the larger the second preset positive threshold; the smaller the remaining capacity, the smaller the second preset positive threshold. Specifically, the adjustment gradient is as follows: for every 0.3m increase in real-time material level, the first preset positive threshold decreases by 12t / h; for every 0.3m decrease in real-time material level, the first preset positive threshold increases by 12t / h. The remaining capacity of the stockpile decreases by 300m³ / h. 3 The second preset positive threshold is reduced by 8 t / h; for every 300 m³ increase in the remaining capacity of the storage yard... 3 The second preset positive threshold is increased by 8 t / h. The adjustment range is limited to: the first preset positive threshold is 40-120 t / h, and the second preset positive threshold is 20-80 t / h, to avoid the threshold deviating excessively from the reasonable range.

[0034] In the above technical solution, flow sensors with a range of 0~3000t / h can be selected to collect various instantaneous flow rates, and these sensors can be installed on the unloader body, the main conveyor belt frame, and the stacker's operating end. Volume detection modules can be used to obtain the remaining capacity of the cargo pile and deployed in various cargo pile areas of the yard. Level detection devices with an accuracy of 0.1m can be used to collect real-time material levels and are fixed inside the buffer hopper cavity. All collected data is uniformly transmitted to a Siemens S7-400 or equivalent industrial programmable logic controller (PLC) for storage and processing. The controller's response time is less than 100ms, meeting real-time scheduling requirements. Set the first preset positive threshold to 80t / h, the first preset negative threshold to -60t / h, the second preset positive threshold to 50t / h, the preset high material level threshold to 2.2m, the preset low capacity threshold to 1200m³, and the preset time threshold to 3-10 seconds. The larger the volume of the buffer hopper, the longer the preset time threshold; the better the material flowability, the shorter the preset time threshold. The preset maximum material level threshold is 90% of the total height of the buffer hopper.

[0035] The above-mentioned operating condition judgment conditions may logically overlap. To avoid command conflicts, the controller judges and executes according to the following priority order: the first priority is "a combined state of insufficient unloader supply and tight yard receiving capacity"; the second priority is "overall congestion"; the third priority is "partial congestion between the unloader and the main conveyor belt" and "partial congestion between the main conveyor belt and the yard" (these two conditions are mutually exclusive and will not be met simultaneously); the fourth priority is "insufficient unloader supply and no overall system congestion"; the lowest priority is "no abnormal operating conditions," maintaining the existing parameters unchanged. Matching is performed level by level in the above order to ensure that only one disposal operation is executed each time.

[0036] For different types of cargo, different equipment models, and different port sizes, the thresholds can be calibrated as follows: the first preset positive threshold is 5%-8% of the rated flow of the ship unloader, the second preset positive threshold is 3%-5% of the rated flow of the main conveyor belt, the third preset positive threshold is 2%-4% of the rated flow of the main conveyor belt, the preset high material level threshold is 70%-80% of the total height of the buffer hopper, and the preset low capacity threshold is 10%-15% of the total capacity of a single stack.

[0037] The equipment continuously collects on-site operational data. The controller sums the instantaneous stacking flow of each stacker to obtain the instantaneous total stacking flow of the stockyard. It then calculates the first difference (unloading flow minus conveying flow) and the second difference (conveying flow minus total stockyard flow) sequentially. These two differences, along with real-time material levels and remaining stockpile capacity, are used to perform condition comparisons. Based on the comparison results, it distinguishes between overall congestion, partial congestion between the unloader and the main conveyor belt, partial congestion between the main conveyor belt and the stockyard, insufficient material supply, and abnormal combined operation states. If no matching condition is found, the equipment's original operating parameters remain unchanged. The parameters are based on the average daily operating flow of conventional bulk cargo at the port, and the threshold values ​​are calibrated according to the stockyard space size. After parameter settings are completed, continuous monitoring and debugging are conducted to adapt to the actual on-site operational rhythm.

[0038] By adopting this technical solution, the present invention can comprehensively collect various dynamic parameters of the operation link, accurately distinguish the operation anomalies caused by different factors, match the corresponding scheduling and control measures according to the actual working conditions, smoothly maintain the operation order of the entire process of unloading, conveying and warehousing, and effectively avoid material flow imbalance and operation blockage.

[0039] In another technical solution, the instantaneous unloading flow rate of the ship unloader is obtained by a first flow sensor installed on the ship unloader; the instantaneous conveying flow rate of the main conveyor belt is obtained by a second flow sensor installed on the main conveyor belt connecting the berth and the stockyard; the instantaneous stacking flow rate of each stacker is obtained by a third flow sensor installed on each stacker in the stockyard; the remaining capacity of each stockpile in the stockyard is obtained by an inventory detection unit installed in the stockyard, which uses a laser scanning ranging system or a millimeter-wave radar array to calculate the volume and remaining capacity of the stockpile in real time through three-dimensional modeling, with a measurement accuracy better than ±5%; the real-time material level is obtained by a buffer hopper set between the ship unloader and the main conveyor belt, with a material level sensor installed in the buffer hopper.

[0040] In the above technical solution, general-purpose belt flow sensors can be used to collect flow rates at each stage. The first flow sensor is installed at the material discharge port of the unloader, the second flow sensor is mounted on the side wall of the main conveyor belt connecting the berth to the stockyard, and the third flow sensors are arranged at the stacking operation ends of each stacker. Intelligent stockyard inventory detection components can be used to count the stockpiled inventory, arranged around the stockpiles. Capacitive level sensors can be used to monitor the material height in the hoppers, embedded inside the buffer hopper cavity. All sensors detect the material conveying volume and stacking height at the corresponding locations in real time, outputting instantaneous flow rate, remaining capacity, and real-time level values ​​respectively. All detection data are aggregated and transmitted to the back-end controller for integrated processing.

[0041] All flow sensors and level sensors are calibrated on-site once a week. Flow sensors are calibrated by physical weighing, and level sensors are calibrated by steel ruler measurement. When dust is severe, level sensors are purged and cleaned every 3 days to avoid dust accumulation that could lead to measurement errors.

[0042] By adopting this technical solution, the present invention clarifies the channels for obtaining various operational parameters, stably outputs accurate and effective on-site detection data, provides complete data support for subsequent numerical calculations and operational condition judgment, and ensures that scheduling decisions are consistent with the actual on-site operational conditions.

[0043] In another technical solution, the overall congestion relief operation is as follows: a speed reduction command is sent to the ship unloader to reduce the instantaneous unloading flow, and a reinforcement command is sent to the yard scheduling system to increase the number of standby stackers; the yard full handling operation is as follows: a speed reduction command is sent to the ship unloader, or a speed reduction command is sent to the main conveyor belt, or both, and an early warning message is issued that the yard is close to full, without adding standby stackers; the material supply compensation operation is as follows: a speed increase command is sent to the ship unloader to increase the instantaneous unloading flow. The specific operation for relieving local congestion is as follows: send a speed reduction command to the ship unloader to reduce the instantaneous unloading flow rate; the specific operation for relieving congestion on the stockyard side is as follows: first, detect the remaining capacity. If the remaining capacity is not lower than the preset low capacity threshold, the controller sends an acceleration command to at least one stacker to increase the instantaneous stacking flow rate; if the remaining capacity is lower than the preset low capacity threshold, the controller determines that the stockyard is close to full and sends a speed reduction command to the ship unloader, or to the main conveyor belt, or to both simultaneously, to reduce the instantaneous conveying flow rate, and at the same time issues a warning message that the stockyard is close to full.

[0044] In the above technical solutions, a general-purpose motor speed control module can be used to adjust the equipment speed, and it can be installed inside the power control cabinet of the unloader and the main conveyor belt; an audible and visual warning component can be used to issue site warning signals, and at the same time issue audible and visual warnings to on-site operators and the central dispatch room, and it can be placed in the yard dispatch operation room and key locations on the work site; a conventional model of the same specification can be used as a backup stacker and parked in the reserved work area of ​​the yard. After the controller identifies the corresponding working conditions, it issues corresponding control commands: during the overall congestion stage, the unloading flow rate is reduced and the number of backup stackers is increased; when the yard capacity is close to the limit, the speed of the unloader or the main conveyor belt is reduced and a warning is triggered, without increasing the number of backup stackers; during the stage of insufficient material supply, the unloading discharge flow rate is increased; during the local congestion between the unloader and the main conveyor belt, only the speed of the unloader is reduced; when there is local congestion between the main conveyor belt and the yard, if the remaining capacity is sufficient, the speed of the stacker is increased, and if the remaining capacity is insufficient, the speed is reduced and a warning is issued.

[0045] By adopting this technical solution, the present invention can flexibly adjust the equipment operating load based on the type of congestion and the current storage capacity, address various operational anomalies in a targeted manner, shorten the duration of abnormal operating conditions, and ensure the steady progress of material conveying operations.

[0046] In another technical solution, the composite state hierarchical cooperative operation is specifically as follows: First, the remaining capacity is checked. If the remaining capacity is not lower than the preset low capacity threshold, it is determined that the yard still has the capacity to accept, and the controller sends an acceleration command to the stacker. If the remaining capacity is lower than the preset low capacity threshold, it is determined that the yard is close to saturation, and the controller sends a deceleration command or a pause command to the unloader, while sending a deceleration command to the main conveyor belt and issuing a yard full alarm. After completing the above operations, if the second difference has recovered to no greater than the second preset positive threshold, and the first difference is still less than the first preset negative threshold, and the remaining capacity is not lower than the preset low capacity threshold, then the controller performs a material supply compensation operation; if the remaining capacity is still lower than the preset low capacity threshold, then the controller maintains the current deceleration or pause state and continues to monitor until the remaining capacity recovers to no less than the preset low capacity threshold before performing the material supply compensation operation.

[0047] In the above technical solution, an industrial logic control module can be selected to divide the operation control levels and integrated into the core controller cabinet; conventional signal lines can be used to complete the transmission of control commands, and are neatly laid out along the support frame of the work site. The operation process first checks the remaining capacity of the stockpile to determine the material receiving capacity: if the remaining capacity is not lower than the low capacity threshold, an acceleration command is sent to the stacker; if the remaining capacity is lower than the low capacity threshold, a deceleration or pause command is sent to the unloader and main conveyor belt, and a site alarm is simultaneously activated. After the second difference returns to a reasonable range (not greater than the second preset positive threshold), the storage capacity is checked again: if the storage capacity has recovered and the first difference is still less than the first preset negative threshold, material supply compensation is directly carried out (increasing the speed of the unloader); if the storage capacity is still insufficient, continuous monitoring is performed, waiting for the storage capacity to recover before executing material supply compensation.

[0048] By adopting this technical solution, the present invention can handle multiple overlapping operational faults in a layered manner, smoothly adjust the operating conditions of the equipment, reduce frequent fluctuations in operating parameters, gradually restore the normal material flow rhythm, and weaken the impact of compound anomalies on the overall operation process.

[0049] In another technical solution, the magnitude of the deceleration or acceleration command is a continuously adjustable value, calculated in real time by the controller based on the first difference, real-time material level, and remaining capacity using a proportional-integral-derivative control algorithm or a model predictive control algorithm. Specifically, the magnitude of the deceleration command satisfies the following: the larger the absolute value of the first difference, the greater the deceleration magnitude; and the higher the real-time material level or the lower the remaining capacity, the greater the deceleration magnitude. Similarly, the magnitude of the acceleration command satisfies the following: the larger the absolute value of the first difference, the greater the acceleration magnitude.

[0050] In the above technical solution, a calculation unit equipped with a proportional-integral-derivative (PID) calculation program or a model prediction calculation program can be selected to calculate the adjustment value. The calculation unit is embedded inside the controller cavity. The speed adjustment range is set to 0~20%. The larger the absolute value of the difference, the greater the corresponding adjustment range. When the material level is high or the silo capacity is low, the speed reduction range increases accordingly. Under the condition of insufficient material supply, the increase in the difference simultaneously increases the speed increase range. The PID algorithm relies on the three parameters of deviation, cumulative deviation, and deviation change rate to calculate the adjustment value and correct the equipment operating parameters in real time. The model prediction control algorithm uses a prediction step size of 10-30 seconds and a control cycle of 5 seconds. It predicts the subsequent operation trend in advance based on the flow rate, material level, and silo capacity data, presets multiple adjustment schemes, and selects the optimal speed adjustment value that matches the current working condition. The controller retrieves three types of parameters: the first difference, the real-time material level, and the remaining capacity. Based on the selected algorithm, it calculates the specific speed adjustment value, determines the final adjustment level according to the matching rules, and sends a continuously adjustable control command to the corresponding equipment. The computing component is made of vibration-resistant metal substrate. The adjustment range is defined by combining the daily flow deviation, and the speed adjustment value under multiple parameter combinations is calculated to ensure that the adjustment range is adapted to the actual degree of imbalance.

[0051] By adopting this technical solution, the present invention enables stable and continuous adjustment of equipment operating speed, avoids operational fluctuations caused by unreasonable speed adjustment, gradually reduces the flow difference between each operational stage, and promotes the material conveying ratio to return to a reasonable operating range.

[0052] In another technical solution, multiple stackers are installed at the end of the main conveyor belt and at the entrance of the stockyard. Each stacker is equipped with a third flow sensor to obtain the instantaneous stacking flow rate of a single stacker. The controller also calculates the difference between the instantaneous conveyor flow rate and the sum of the instantaneous stacking flows of all stackers, which is recorded as the third difference, and monitors the operating status of each stacker. When the third difference is greater than a third preset positive threshold and the duration exceeds a preset time threshold, the controller determines that the congestion is caused by insufficient stacking capacity. If the current instantaneous stacking flow rate of at least one operating stacker does not reach its rated capacity, an acceleration command is sent to at least one stacker that has not reached its rated capacity. If the current instantaneous stacking flow rate of all operating stackers has reached its rated capacity, a standby stacker is started.

[0053] In the above technical solution, a general-purpose flow detection device can be used to collect the instantaneous flow rate of the stockpiled material. The detection device is fixedly installed at the working end of the stockpile crane at the entrance of the stockpile yard. A third preset positive threshold of 45 t / h is set, and its calibration method is as follows: take 2%-4% of the rated flow rate of the main conveyor belt, and use the rated operating flow rate of the equipment at the factory as the reference for judging the stockpiling capacity. The sensor collects the stockpiling operation flow rate data in real time, and the controller calculates the third difference (the instantaneous conveying flow rate of the main conveyor belt minus the sum of the instantaneous stockpiling flow rates of all stockpilers). When the third difference is greater than the third preset positive threshold and the duration exceeds the preset time threshold, it is judged to be a congestion caused by insufficient stockpiling capacity. After confirming the abnormality, an acceleration command is issued according to the equipment operating status, or a backup stockpiling equipment is started for operation.

[0054] By adopting this technical solution, the present invention extends the scope of control to the stockpile process, promptly detects blockages and faults in the stockpile process, makes up for gaps in operational capacity, and ensures that materials are smoothly transported to the stockpile to complete the stockpile operation.

[0055] In another technical solution, after the controller determines that the congestion is caused by insufficient stacking capacity, it first obtains the remaining capacity of all currently operating stack positions. If the remaining capacity is not lower than the preset low capacity threshold, then the operation of sending an acceleration command to the stacker or starting the standby stacker will be executed. If the remaining capacity is lower than the preset low capacity threshold, the controller further checks whether there are other vacant stacks in the yard with a remaining capacity not lower than the preset low capacity threshold. If there are vacant stacks, the controller sends a transfer command to the yard scheduling system, controls one of the stackers to move to the vacant stack, and reduces the instantaneous conveying flow of the main conveyor belt to zero during the transfer. After the stacker is in place at the vacant stack, the instantaneous conveying flow of the main conveyor belt is restored to the value before the reduction. If there are no vacant stacks, the controller determines that the yard is full and does not perform the transfer operation. Instead, it performs yard full handling, that is, it sends a speed reduction command to the unloader, or a speed reduction command to the main conveyor belt, or simultaneously sends a speed reduction command to both the unloader and the main conveyor belt, and issues a warning message that the yard is close to full.

[0056] In the above technical solutions, a space positioning and detection device can be used to locate vacant stacking positions, which can be installed on a support frame at the top of the yard; a flow control component can be used to manage the running speed of the main conveyor belt, which can be installed inside the power control box of the conveyor belt. Upon detecting congestion, the remaining capacity of all current stacking positions is checked first: if the remaining capacity is not lower than the preset low capacity threshold, the stacking operation status is directly adjusted (an acceleration command is sent to the stacker or a backup stacker is started); if the remaining capacity of the current stacking position is lower than the low capacity threshold, other vacant stacking positions in the yard with remaining capacities not lower than the low capacity threshold are searched: if vacant stacking positions exist, a transfer operation is performed; if no vacant areas exist, the yard full storage disposal process is initiated (a deceleration command is sent to the unloader or main conveyor belt and an early warning is issued).

[0057] By adopting this technical solution, the present invention fully utilizes the existing storage space of the yard, flexibly switches the working stacks to reduce space idleness and waste, reduces the frequency of full-load shutdowns, and fully leverages the material storage capacity of the yard.

[0058] In another technical solution, the specific method of position transfer is as follows: The controller obtains the real-time material level of the buffer hopper and calculates the current remaining available volume of the buffer hopper; at the same time, it obtains the estimated movement time required for the stacker to move from the current stack position to the target empty stack position. The controller calculates a safe flow rate for the unloader based on the remaining available volume and the estimated travel time. This safe flow rate is equal to the quotient obtained by multiplying the remaining available volume by the material bulk density and then dividing by the estimated travel time. The material bulk density is preset according to the current type of cargo being unloaded; for example, 0.8-0.9 t / m³ for coal. 3 Iron ore yield is 2.2-2.6 t / m³. 3 Grain yield is 0.7-0.8 t / m³. 3 ; During the transfer operation, the controller sends a speed reduction command to the unloader, reducing the instantaneous unloading flow rate of the unloader to no more than the safe flow rate value of the unloader; at the same time, the controller sends a stop command to the main conveyor belt, reducing the instantaneous conveying flow rate of the main conveyor belt to zero; at the same time, it monitors the real-time material level of the buffer hopper, and stops the unloader immediately when the material level reaches the preset maximum material level. After the stacker is in place in an empty stacking position and the stacker arm is aligned, the controller first starts the main conveyor belt. After the main conveyor belt runs stably, the instantaneous unloading flow of the unloader is gradually restored to the value before the transfer operation. Then the first difference and the second difference are recalculated, and the status is judged based on the real-time material level and remaining capacity.

[0059] In the above technical solution, a time-based statistics module can be selected to calculate the equipment movement time, and it can be installed in the electrical control part of the stacker's traveling mechanism; a volumetric calculation component can be selected to calculate the available storage space of the hopper, and it can be installed on the inner side wall of the buffer hopper. By dividing the remaining available volume of the buffer hopper (total volume minus occupied volume) by the estimated movement time of the stacker from the current stack position to the target empty stack position, the safe flow rate of the unloader is calculated. During the transfer phase, the unloading flow rate is controlled within the calculated range, and the material conveying operation of the main conveyor belt is suspended (the instantaneous conveying flow rate is reduced to zero). After the stacker arrives at the target stack position, all operating parameters before the transfer operation are restored (the unloading flow rate and conveying flow rate are restored to their original values), and routine working condition judgment and scheduling work is restarted.

[0060] By adopting this technical solution, the present invention standardizes and controls the material conveying status throughout the entire warehouse transfer process, avoids material accumulation or material shortage during the transfer, ensures the safe operation of equipment transfer, and maintains the continuous and uninterrupted operation of the overall unloading process.

[0061] When a single stacker is detected to be malfunctioning, the controller automatically deducts the instantaneous stacking flow of that stacker from the total instantaneous stacking flow of the stockyard and recalculates the second and third differences. If the total stacking flow of the remaining operating stackers cannot meet the conveying demand and there are available standby stackers, the standby stacker is automatically started. If there are no available standby stackers, a speed reduction command is automatically sent to the unloader to reduce the instantaneous unloading flow to 90% of the remaining total stacking flow, thus preventing material accumulation without manual intervention.

[0062] In this invention, the controller also monitors fault signals from the ship unloader, main conveyor belt, and each stacker in real time. When a fault is detected in the ship unloader or main conveyor belt, the controller skips all condition judgment steps based on flow difference, no longer calculates the first, second, and third differences, and no longer makes any judgments on congestion or insufficient material supply. Instead, it directly issues a shutdown command or maintenance alarm command to prioritize the safety of equipment and personnel.

[0063] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and embodiments shown and described herein.

Claims

1. A method for coordinated scheduling of bulk cargo port berths and storage yards for unloading operations, characterized in that, Includes the following steps: The instantaneous unloading flow rate of the ship unloader, the instantaneous conveying flow rate of the main conveyor belt, the instantaneous stacking flow rate of each stacker, the remaining capacity of each stockpile in the yard, and the real-time material level are obtained and transmitted to the controller. The controller sums up the instantaneous stacking flow rates of each stacker to obtain the total instantaneous stacking flow rate of the stockyard; Calculate the difference between the instantaneous unloading flow rate and the instantaneous conveying flow rate, and record it as the first difference; calculate the difference between the instantaneous conveying flow rate and the instantaneous total stockpile flow rate in the stockyard, and record it as the second difference; and make the following judgments based on the first difference, the second difference, and the real-time material level: When the first difference is greater than the first preset positive threshold, the second difference is greater than the second preset positive threshold, and the real-time material level is higher than the preset high material level threshold for a duration exceeding the preset time threshold, the remaining capacity is further detected: if the remaining capacity is not lower than the preset low capacity threshold, the controller determines that there is overall congestion and performs overall congestion relief operation; if the remaining capacity is lower than the preset low capacity threshold, the controller determines that the system congestion is caused by the yard being close to full capacity and performs yard full capacity processing. When the first difference is greater than the first preset positive threshold, the second difference is not greater than the second preset positive threshold, and the real-time material level is higher than the preset high material level threshold and the duration exceeds the preset time threshold, it is judged as a local congestion between the ship unloader and the main conveyor belt, and a local congestion relief operation is performed. When the first difference is not greater than the first preset positive threshold and not less than the first preset negative threshold, and the second difference is greater than the second preset positive threshold and the duration exceeds the preset time threshold, it is determined that there is a local congestion between the main conveyor belt and the stockyard, and a stockyard-side decongestion operation is performed. When the first difference is less than the first preset negative threshold, the second difference is not greater than the second preset positive threshold, the remaining capacity is not lower than the preset low capacity threshold, and the duration exceeds the preset time threshold, the controller determines that the unloader is not supplying enough material and the system is not congested as a whole, and performs a material supply compensation operation. When the first difference is less than the first preset negative threshold and the second difference is greater than the second preset positive threshold and the duration exceeds the preset time threshold, it is judged to be a composite state of insufficient material supply from the unloader accompanied by tight storage capacity in the yard, and a composite state hierarchical collaborative operation is executed; In the case where it does not fall into any of the above states, the controller maintains the current operating parameters of each device unchanged and continues to monitor. The controller dynamically adjusts the first preset positive threshold based on the real-time material level: the higher the real-time material level, the lower the first preset positive threshold; the lower the real-time material level, the higher the first preset positive threshold. The controller also dynamically adjusts the second preset positive threshold based on the remaining capacity: the higher the remaining capacity, the higher the second preset positive threshold; the lower the remaining capacity, the lower the second preset positive threshold.

2. The method for coordinated scheduling of bulk cargo port berths and storage yards for unloading operations as described in claim 1, characterized in that, The instantaneous unloading flow rate of the ship unloader is obtained through a first flow sensor installed on the ship unloader; the instantaneous conveying flow rate of the main conveyor belt is obtained through a second flow sensor installed on the main conveyor belt connecting the berth and the stockyard; the instantaneous stacking flow rate of each stacker is obtained through a third flow sensor installed on each stacker in the stockyard; the remaining capacity of each stockpile in the stockyard is obtained through an inventory detection unit installed in the stockyard; and the real-time material level is obtained through a buffer hopper installed between the ship unloader and the main conveyor belt, with a material level sensor installed in the buffer hopper.

3. The method for coordinated scheduling of bulk cargo port berths and storage yards for unloading operations as described in claim 2, characterized in that, The overall congestion relief operation is as follows: a speed reduction command is sent to the ship unloader to reduce the instantaneous unloading flow, and a reinforcement command is sent to the yard dispatch system to increase the number of standby stackers; the yard full handling operation is as follows: a speed reduction command is sent to the ship unloader, or a speed reduction command is sent to the main conveyor belt, or both, and an early warning message is issued that the yard is close to full, without adding standby stackers; the material supply compensation operation is as follows: a speed increase command is sent to the ship unloader to increase the instantaneous unloading flow. The specific operation for relieving local congestion is as follows: send a speed reduction command to the ship unloader to reduce the instantaneous unloading flow rate; the specific operation for relieving congestion on the stockyard side is as follows: first, detect the remaining capacity. If the remaining capacity is not lower than the preset low capacity threshold, the controller sends an acceleration command to at least one stacker to increase the instantaneous stacking flow rate; if the remaining capacity is lower than the preset low capacity threshold, the controller determines that the stockyard is close to full and sends a speed reduction command to the ship unloader, or to the main conveyor belt, or to both simultaneously, to reduce the instantaneous conveying flow rate, and at the same time issues a warning message that the stockyard is close to full.

4. The method for coordinated scheduling of bulk cargo port berths and storage yards for unloading operations as described in claim 3, characterized in that, The specific details of the composite state hierarchical cooperative operation are as follows: First, the remaining capacity is checked. If the remaining capacity is not lower than the preset low capacity threshold, it is determined that the yard still has the capacity to accept, and the controller sends an acceleration command to the stacker. If the remaining capacity is lower than the preset low capacity threshold, it is determined that the yard is close to saturation, and the controller sends a deceleration command or a pause command to the unloader, while sending a deceleration command to the main conveyor belt and issuing a yard full alarm. After completing the above operations, if the second difference has recovered to no greater than the second preset positive threshold, and the first difference is still less than the first preset negative threshold, and the remaining capacity is not lower than the preset low capacity threshold, then the controller performs a material supply compensation operation; if the remaining capacity is still lower than the preset low capacity threshold, then the controller maintains the current deceleration or pause state and continues to monitor until the remaining capacity recovers to no less than the preset low capacity threshold before performing the material supply compensation operation.

5. The method for coordinated scheduling of bulk cargo port berths and storage yards for unloading operations as described in claim 1, characterized in that, The magnitude of the deceleration or acceleration command is a continuously adjustable value, calculated in real time by the controller based on the first difference, real-time material level, and remaining capacity using a proportional-integral-derivative control algorithm or a model predictive control algorithm. Specifically, the magnitude of the deceleration command satisfies the following: the larger the absolute value of the first difference, the larger the deceleration magnitude; and the higher the real-time material level or the lower the remaining capacity, the larger the deceleration magnitude. The magnitude of the acceleration command satisfies the following: the larger the absolute value of the first difference, the larger the acceleration magnitude.

6. The method for coordinated scheduling of bulk cargo port berths and storage yards for unloading operations as described in claim 1, characterized in that, Multiple stackers are located at the end of the main conveyor belt and at the entrance of the stockyard. Each stacker is equipped with a third flow sensor to obtain the instantaneous stacking flow rate of a single stacker. The controller also calculates the difference between the instantaneous conveyor flow rate and the sum of the instantaneous stacking flows of all stackers, which is recorded as the third difference, and monitors the operating status of each stacker. When the third difference is greater than the third preset positive threshold and the duration exceeds the preset time threshold, the controller determines that the congestion is caused by insufficient stacking capacity. If the current instantaneous stacking flow rate of at least one operating stacker does not reach its rated capacity, an acceleration command is sent to at least one stacker that has not reached its rated capacity. If the current instantaneous stacking flow rate of all operating stackers has reached its rated capacity, a standby stacker is started.

7. The method for coordinated scheduling of bulk cargo port berths and storage yards for unloading operations as described in claim 6, characterized in that, After determining that the congestion is caused by insufficient stacking capacity, the controller first obtains the remaining capacity of all currently operating stack positions; If the remaining capacity is not lower than the preset low capacity threshold, then the operation of sending an acceleration command to the stacker or starting the standby stacker will be executed. If the remaining capacity is lower than the preset low capacity threshold, the controller further checks whether there are other vacant stacks in the yard with a remaining capacity not lower than the preset low capacity threshold. If there are vacant stacks, the controller sends a transfer command to the yard scheduling system, controls one of the stackers to move to the vacant stack, and reduces the instantaneous conveying flow of the main conveyor belt to zero during the transfer. After the stacker is in place at the vacant stack, the instantaneous conveying flow of the main conveyor belt is restored to the value before the reduction. If there are no vacant stacks, the controller determines that the yard is full and does not perform the transfer operation. Instead, it performs yard full handling, that is, it sends a speed reduction command to the unloader, or a speed reduction command to the main conveyor belt, or simultaneously sends a speed reduction command to both the unloader and the main conveyor belt, and issues a warning message that the yard is close to full.

8. The method for coordinated scheduling of bulk cargo port berths and storage yards for unloading operations as described in claim 7, characterized in that, The specific steps for rolling over positions are as follows: The controller obtains the real-time material level of the buffer hopper and calculates the current remaining available volume of the buffer hopper; at the same time, it obtains the estimated movement time required for the stacker to move from the current stack position to the target empty stack position. The controller calculates a safe flow rate value for the unloader based on the remaining available volume and the estimated travel time. This safe flow rate value is equal to the quotient obtained by multiplying the remaining available volume by the material bulk density and then dividing by the estimated travel time. The material bulk density is preset according to the current type of cargo being unloaded. During the transfer operation, the controller sends a speed reduction command to the unloader, reducing the instantaneous unloading flow rate of the unloader to no more than the safe flow rate value of the unloader; at the same time, the controller sends a stop command to the main conveyor belt, reducing the instantaneous conveying flow rate of the main conveyor belt to zero; at the same time, it monitors the real-time material level of the buffer hopper, and stops the unloader immediately when the material level reaches the preset maximum material level. After the stacker is in place in an empty stacking position and the stacker arm is aligned, the controller first starts the main conveyor belt. After the main conveyor belt runs stably, the instantaneous unloading flow of the unloader is gradually restored to the value before the transfer operation. Then the first difference and the second difference are recalculated, and the status is judged based on the real-time material level and remaining capacity.