A hydraulic system with a two-speed control loop and its control method

Abstract

The present invention discloses a hydraulic system with a two-speed control circuit and its control method, which relates to the field of customs quarantine. The system includes: a hydraulic cylinder assembly, which includes a hydraulic cylinder and a displacement sensor; a first hydraulic lock; a fast circuit assembly, and the fast circuit assembly, the first hydraulic lock and the hydraulic cylinder assembly are connected through pipelines to form a fast adjustment subsystem; a slow circuit assembly, and the slow circuit assembly, the first hydraulic lock and the hydraulic cylinder assembly are connected to form a slow adjustment subsystem. By adopting a combination of a hydraulic lock and a dual circuit, the position of the hydraulic cylinder is maintained more reliably, and a stable operating state can also be maintained under extreme working conditions. The present invention provides an efficient, precise, stable and low-cost control solution for hydraulic cylinders, which is widely applicable to hydraulic systems that require fast adjustment and precise positioning.

Description

Technical Field

[0001] The present invention relates to the field of hydraulic systems, and more particularly, to a hydraulic system with a two-speed control circuit and its control method. Background Art

[0002] In many application scenarios of hydraulic cylinders, especially in industrial equipment and construction machinery, it is often necessary to precisely adjust the speed and displacement of the hydraulic cylinder. Existing solutions mainly rely on servo valves or proportional valves.

[0003] The servo valve can achieve precise flow control to adjust the speed and displacement of the hydraulic cylinder. However, during high-speed movement, the servo valve needs to provide sufficient oil supply, resulting in serious system heating and large pressure losses. At the same time, the servo valve has high requirements for oil cleanliness (generally reaching NAS 6 level or above), and is easily contaminated by welding slag, iron filings, etc. during on-site installation, affecting its service life.

[0004] The proportional valve has a lower cost than the servo valve, but its control accuracy is poor and it cannot meet high-precision requirements, especially it is difficult to ensure the positioning accuracy under low-speed fine-tuning conditions.

[0005] It is necessary to propose a hydraulic system and its control method to solve at least some of the above problems. Summary of the Invention

[0006] A series of simplified concepts are introduced in the Summary of the Invention section, which will be further elaborated in the Detailed Description section. The Summary of the Invention section of this application does not mean to attempt to define the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the protection scope of the claimed technical solution.

[0007] In a first aspect, the present application proposes a hydraulic system with a two-speed control circuit, including:

[0008] A hydraulic cylinder assembly, where the hydraulic cylinder assembly includes a hydraulic cylinder and a displacement sensor;

[0009] A first hydraulic lock;

[0010] A fast circuit assembly, where the fast circuit assembly, the first hydraulic lock, and the hydraulic cylinder assembly are connected by pipelines to form a fast adjustment subsystem;

[0011] A slow circuit assembly, where the slow circuit assembly, the first hydraulic lock, and the hydraulic cylinder assembly are connected to form a slow adjustment subsystem.

[0012] In a feasible implementation, the fast circuit assembly includes an electromagnetic directional valve, a first balance valve, and a second hydraulic lock;

[0013] The first opening of the electromagnetic directional valve is connected to the pressure oil inlet P, the second opening of the electromagnetic directional valve is connected to the pressure oil outlet T, the third outlet of the electromagnetic directional valve is connected to the first opening of the first balance valve, the second opening of the first balance valve is connected to port A of the hydraulic cylinder assembly, the second hydraulic lock is connected to port B of the hydraulic cylinder assembly and the fourth opening of the electromagnetic directional valve, the hydraulic cylinder assembly includes port A and port B, port A is used for the input of hydraulic oil, port B is used for the return of hydraulic oil, the electromagnetic directional valve is a four-way valve, the electromagnetic directional valve includes four openings, the first opening of the electromagnetic directional valve is the pressure oil inlet of the electromagnetic directional valve, the second opening of the electromagnetic directional valve is the oil return port of the electromagnetic directional valve, the third opening of the electromagnetic directional valve is used to control the extension of the hydraulic cylinder assembly, and the fourth opening of the electromagnetic directional valve is used to control the retraction of the hydraulic cylinder assembly.

[0014] In a feasible implementation manner, the slow-speed circuit assembly includes a third hydraulic lock, a fourth hydraulic lock, a fifth hydraulic lock, a second balance valve, a first overflow valve, a second overflow valve, a solenoid valve, and a bi-directional servo pump set;

[0015] The first opening of the third hydraulic lock is connected to port B of the hydraulic cylinder assembly, and the second opening of the third hydraulic lock is connected to port B1 of the bi-directional servo pump set through a first pipeline;

[0016] The first opening of the second balance valve is connected to port A of the hydraulic cylinder assembly, and the second opening of the second balance valve is connected to port A1 of the bi-directional servo pump set through a second pipeline;

[0017] The first port of the solenoid valve is connected to the second pipeline, and the second port of the solenoid valve is connected to the pressure oil outlet T through a third pipeline;

[0018] The fourth hydraulic lock and the fifth hydraulic lock connect the first pipeline and the second pipeline, and a make-up oil pipeline is also connected between the fourth hydraulic lock and the fifth hydraulic lock;

[0019] The first overflow valve and the second overflow valve connect the first pipeline and the second pipeline, and the third pipeline is also connected between the first overflow valve and the second overflow valve. The bi-directional servo pump set includes a servo motor and a variable displacement piston pump. The servo motor drives the variable displacement piston pump to rotate forward or backward to achieve the bi-directional flow of hydraulic oil.

[0020] In a second aspect, the present application proposes a control method for the two-speed control loop hydraulic system described in the first aspect, including:

[0021] Obtain the current load information, current stroke information, rated load information of the hydraulic cylinder, environmental information, control mode information, and target stroke information of the above-mentioned two-speed control loop hydraulic system;

[0022] Control the working states of the above-mentioned fast loop component and the above-mentioned slow loop component according to the above-mentioned current load information, the above-mentioned current stroke information, the above-mentioned rated load information of the hydraulic cylinder, the above-mentioned environmental information, the above-mentioned control mode information, and the above-mentioned target stroke information.

[0023] In a feasible implementation manner, the working state of the above-mentioned fast loop component includes the target stroke of the fast loop component and the loading speed of the fast loop component, and the working state of the above-mentioned slow loop component includes the target stroke of the slow loop component and the loading speed of the fast loop component;

[0024] The above-mentioned controlling the working states of the above-mentioned fast loop component and the above-mentioned slow loop component according to the above-mentioned current load information, the above-mentioned current stroke information, the above-mentioned rated load information of the hydraulic cylinder, the above-mentioned environmental information, the above-mentioned control mode information, and the above-mentioned target stroke information includes:

[0025] Determine the target stroke of the above-mentioned fast loop component and the target stroke of the above-mentioned slow loop component according to the above-mentioned current load information, the above-mentioned current stroke information, the above-mentioned rated load information of the hydraulic cylinder, the above-mentioned environmental information, the above-mentioned control mode information, and the above-mentioned target stroke information;

[0026] When the current working condition is for the above-mentioned fast loop component to work, control the loading speed of the above-mentioned fast loop component according to the above-mentioned current load information, the above-mentioned current stroke information, the above-mentioned control mode information, and the target stroke information;

[0027] When the current working condition is for the above-mentioned slow loop component to work, control the loading speed of the above-mentioned slow loop component according to the above-mentioned current load information, the above-mentioned current stroke information, the above-mentioned control mode information, and the target stroke information.

[0028] In a feasible implementation manner, the above-mentioned determining the target stroke of the above-mentioned fast loop component and the target stroke of the above-mentioned slow loop component according to the above-mentioned current load information, the above-mentioned current stroke information, the above-mentioned rated load information of the hydraulic cylinder, the above-mentioned environmental information, the above-mentioned control mode information, and the above-mentioned target stroke information includes:

[0029] Construct a feature vector according to the above-mentioned current load information, the above-mentioned current stroke information, the above-mentioned rated load information of the hydraulic cylinder, the above-mentioned environmental information, and the above-mentioned target stroke information;

[0030] Define a state space according to the above-mentioned feature vector;

[0031] Establish a reinforcement learning action according to the fast adjustment ratio and the slow adjustment ratio;

[0032] Determine the reward function according to the above control mode, where the above reward function includes a positioning accuracy term, a time efficiency term, and an energy consumption term;

[0033] Establish a reinforcement learning model based on the above state space, the above reinforcement learning actions, and the above reward function to obtain the initial ratio of fast adjustment and slow adjustment;

[0034] Determine the adjustment ratio of fast adjustment and slow adjustment according to the above current load information, the above current travel information, the above target travel information, and the fuzzy rule base;

[0035] Determine the target travel of the above fast loop component and the target travel of the above slow loop component according to the above initial ratio of fast adjustment and slow adjustment and the adjustment ratio of fast adjustment and slow adjustment.

[0036] In a feasible implementation manner, the above controlling the loading speed of the above fast loop component according to the above current load information, the above current travel information, the above control mode information, and the target travel information includes:

[0037] Determine the dynamic coefficient according to the above current load information, the above current travel information, the above control mode information, and the target travel information;

[0038] Construct an adaptive PID control model according to the above dynamic coefficient;

[0039] Control the loading speed of the above fast loop component based on the above adaptive PID control model.

[0040] In a feasible implementation manner, the above controlling the loading speed of the above slow loop component according to the above current load information, the above current travel information, the above control mode information, and the target travel information includes:

[0041] Control and determine the objective function according to the above current load information, the above current travel information, the above control mode information, and the target travel information, where the above objective function includes a position error term, a speed smoothness term, an acceleration smoothness term, and a load adaptability term;

[0042] Determine the weight coefficient of the above objective function according to the above control mode information;

[0043] Control the loading speed of the above slow loop component according to the above objective function and the quadratic programming method.

[0044] In a feasible implementation manner, it further includes:

[0045] When the current working condition is that the above-mentioned fast loop component is working and the above-mentioned environmental information exceeds the preset environmental threshold for the first duration, reduce the loading speed of the above-mentioned fast loop component and generate a first warning message;

[0046] After reducing the loading speed of the above-mentioned fast loop component for the second duration, when the above-mentioned environmental information still exceeds the preset environmental threshold, switch to the slow loop component loading mode and generate a second warning message.

[0047] In a feasible implementation manner, it further includes:

[0048] After running for the third duration in the above-mentioned slow loop component loading mode, when the above-mentioned environmental information still exceeds the preset environmental threshold, suspend the loading and generate a third warning message, where the above-mentioned first duration, the above-mentioned second duration, and the above-mentioned third duration are determined according to the abnormal degree of the environmental information. The above-mentioned first duration is used to judge the temporary loading speed adjustment time of the fast loop component, the above-mentioned second duration is used for the switching time when the abnormality has not recovered, and the above-mentioned third duration is used for the suspension loading time when the slow loop component still cannot return to normal.

[0049] In summary, in this implementation, through the combined use of the fast loop component and the slow loop component, the hydraulic cylinder is provided with a large flow of oil by the fast loop component during the fast forward and reverse stages, and a small flow of oil by the slow loop component during the precise forward and reverse stages, thereby reducing energy consumption. The design of the slow loop component ensures that the hydraulic cylinder can still maintain a high control accuracy during low-speed working feed, realizing fine adjustment and position holding. Compared with the heating problem caused by the continuous high-load operation of the servo valve, in this embodiment, the fast and slow loops work in stages, avoiding excessive heat generation in the system due to continuous high-flow oil supply. Since it no longer completely relies on the servo valve, the strict requirements for the cleanliness of the oil are reduced. The pipelines and oil tanks of the hydraulic system do not have to adopt expensive stainless steel materials, reducing the equipment cost and maintenance difficulty. By adopting the combination of hydraulic locks and double loops, the position holding of the hydraulic cylinder is more reliable, and it can also maintain a stable operating state under extreme working conditions. In summary, this embodiment provides an efficient, precise, stable and low-cost hydraulic cylinder control solution, which is widely applicable to hydraulic systems that require rapid adjustment and precise positioning.

[0050] Other advantages, objectives and features of this application will be partially reflected by the following description, and partially will also be understood by those skilled in the art through the research and practice of this application. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the following detailed description of the preferred embodiments. The drawings are only for the purpose of illustrating the preferred embodiments and are not considered to be a limitation of this specification. Also, throughout the drawings, the same reference numerals are used to denote the same components. In the drawings:

[0052] Figure 1 FIG. is a structural schematic diagram of a hydraulic system for a two-speed control loop provided by an embodiment of the present application;

[0053] Figure 2 FIG.

[0052] is a schematic diagram of the principle of a hydraulic system for a two-speed control loop provided by an embodiment of the present application;

[0054] Figure 3 FIG. Figure 1 is a schematic flowchart of a control method for a hydraulic system of a two-speed control loop provided by an embodiment of the present application;

[0055] Figure 1 and Figure 2 The corresponding relationship between the reference numerals and the names of the drawings in FIGS. and

[0052] is as follows:

[0056] 10 Hydraulic cylinder assembly, 20 First hydraulic lock, 30 Quick circuit assembly, 40 Slow circuit assembly;

[0057] 301 Electromagnetic directional valve, 302 First balance valve, 303 Second hydraulic lock;

[0058] 401 Third hydraulic lock, 402 Fourth hydraulic lock, 403 Fifth hydraulic lock, 404 Second balance valve, 405 First relief valve, 406 Second relief valve, 407 Solenoid valve, 408 Bidirectional servo pump group, 409 First pipeline, 410 Second pipeline, 411 Third pipeline, 412 Make-up oil pipeline. Detailed Embodiments

[0059] In the description and claims of this application and the above-mentioned drawings, terms such as "first", "second", "third", "fourth", etc. (if any) are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments described here can be implemented in an order different from that shown or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices. Next, the technical solutions in the embodiments of this application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all of the embodiments.

[0060] Please refer to Figure 1 and Figure 2 , Figure 1 which is a structural schematic diagram of a hydraulic system for a two-speed control loop provided by an embodiment of this application; Figure 2 which is a schematic diagram of the principle of a hydraulic system for a two-speed control loop provided by an embodiment of this application. The system may specifically include:

[0061] A hydraulic cylinder assembly 10, and the above-mentioned hydraulic cylinder assembly 10 includes a hydraulic cylinder 101 and a displacement sensor 102;

[0062] A first hydraulic lock 20;

[0063] A fast circuit assembly 30. The above-mentioned fast circuit assembly 30, the above-mentioned first hydraulic lock 20, and the above-mentioned hydraulic cylinder assembly 10 are connected by pipelines to form a fast adjustment subsystem;

[0064] A slow circuit assembly 40. The above-mentioned slow circuit assembly 40, the above-mentioned first hydraulic lock 20, and the above-mentioned hydraulic cylinder assembly 10 are connected to form a slow adjustment subsystem.

[0065] Exemplarily, this embodiment provides a hydraulic cylinder assembly, including a hydraulic cylinder assembly 10, a first hydraulic lock 20, a fast circuit assembly 30, and a slow circuit assembly 40.

[0066] The hydraulic cylinder assembly 10 includes a hydraulic cylinder 101 and a displacement sensor 102. The hydraulic cylinder 101 is used to perform reciprocating linear motion to achieve the pushing and pulling functions. The displacement sensor 102 is used to detect the actual position and displacement of the hydraulic cylinder to provide a feedback signal for the control system to adjust.

[0067] The first hydraulic lock 20 is used to lock the position of the hydraulic cylinder when necessary to prevent the load from sliding down or shifting in position. The hydraulic lock has a self-locking function and can maintain the position of the hydraulic cylinder when the machine stops or the power is cut off.

[0068] The quick circuit assembly 30 is connected to the hydraulic cylinder assembly 10 and the first hydraulic lock 20 through pipelines to form a quick adjustment subsystem. This circuit is mainly used for the quick advance and retreat of the hydraulic cylinder. When the hydraulic cylinder needs to quickly approach or retract, the quick circuit assembly drives the hydraulic cylinder with a larger oil supply volume to shorten the non-working stroke time and improve the operation efficiency.

[0069] The slow circuit assembly 40 is also connected to the hydraulic cylinder assembly 10 and the first hydraulic lock 20 through pipelines to form a slow adjustment subsystem. It is used for the precise fine-tuning of the hydraulic cylinder. When the hydraulic cylinder needs to perform precise positioning or load control at a lower speed, the slow circuit assembly adjusts through precise oil supply with a small flow rate to achieve smooth and precise movement.

[0070] In summary, in this embodiment, through the combined use of the quick circuit assembly and the slow circuit assembly, the hydraulic cylinder is provided with a large flow rate of oil by the quick circuit assembly during the quick advance and retreat stages, and a small flow rate of oil by the slow circuit assembly during the precise advance and retreat stages, thereby reducing energy consumption. The design of the slow circuit assembly ensures that the hydraulic cylinder can still maintain a high control accuracy during the low-speed working feed, realizing fine adjustment and position holding. Compared with the heating problem caused by the continuous high-load operation of the servo valve, in this embodiment, the quick and slow circuits work in stages, avoiding excessive heat generation in the system due to continuous high-flow oil supply. Since it no longer completely relies on the servo valve, the strict requirements for the cleanliness of the oil are reduced. The pipelines and oil tank of the hydraulic system do not need to use expensive stainless steel materials, reducing the equipment cost and maintenance difficulty. By adopting the combination of the hydraulic lock and the dual circuit, the position holding of the hydraulic cylinder is more reliable, and it can also maintain a stable operating state under extreme working conditions. In summary, this embodiment provides an efficient, precise, stable and low-cost hydraulic cylinder control solution, which is widely applicable to hydraulic systems that require quick adjustment and precise positioning.

[0071] In a feasible implementation manner, the above-mentioned quick circuit assembly includes an electromagnetic directional valve, a first balance valve and a second hydraulic lock;

[0072] The first opening of the electromagnetic directional control valve is connected to the pressure oil inlet P, the second opening of the electromagnetic directional control valve is connected to the pressure oil outlet T, the third outlet of the electromagnetic directional control valve is connected to the first opening of the first balance valve, the second opening of the first balance valve is connected to port A of the hydraulic cylinder assembly, the second hydraulic lock is connected to port B of the hydraulic cylinder assembly and the fourth opening of the electromagnetic directional control valve, the hydraulic cylinder assembly includes port A and port B, port A is used for the input of hydraulic oil, port B is used for the return of hydraulic oil, the electromagnetic directional control valve is a four-way valve, the electromagnetic directional control valve includes four openings, the first opening of the electromagnetic directional control valve is the pressure oil inlet of the electromagnetic directional control valve, the second opening of the electromagnetic directional control valve is the oil return port of the electromagnetic directional control valve, the third opening of the electromagnetic directional control valve is used to control the extension of the hydraulic cylinder assembly, and the fourth opening of the electromagnetic directional control valve is used to control the retraction of the hydraulic cylinder assembly.

[0073] Exemplarily, the quick circuit assembly 30 is connected to the hydraulic cylinder assembly 10 and the first hydraulic lock 20 through pipelines to form a quick adjustment subsystem. This circuit is mainly used for the quick forward and backward movement of the hydraulic cylinder. When the hydraulic cylinder needs to quickly approach or withdraw, the quick circuit assembly drives the hydraulic cylinder with a larger oil supply to shorten the non-working stroke time and improve the operation efficiency.

[0074] The quick circuit assembly 30 includes an electromagnetic directional control valve 301, a first balance valve 302 and a second hydraulic lock 303.

[0075] The first opening of the electromagnetic directional control valve 301 is connected to the pressure oil inlet P, the second opening is connected to the pressure oil outlet T, the third opening is connected to the first opening of the first balance valve 302, and the fourth opening is connected to the second hydraulic lock 303.

[0076] The second opening of the first balance valve 302 is connected to port A of the hydraulic cylinder assembly 10, which is used to control the movement direction and speed of the hydraulic cylinder piston rod and ensure the stable operation of the hydraulic cylinder at the same time.

[0077] The second hydraulic lock 303 is connected to port B of the hydraulic cylinder assembly 10 and is used to lock the position of the hydraulic cylinder when necessary to prevent accidental movement.

[0078] Through the cooperation of the electromagnetic directional control valve 301, the first balance valve 302 and the second hydraulic lock 303, the quick circuit assembly 30 realizes the quick movement of the hydraulic cylinder and ensures the safety and reliability of the operation process at the same time.

[0079] In a feasible implementation manner, the slow circuit assembly includes a third hydraulic lock, a fourth hydraulic lock, a fifth hydraulic lock, a second balance valve, a first overflow valve, a second overflow valve, an electromagnetic valve and a two-way servo pump group;

[0080] The first opening of the third hydraulic lock is connected to port B of the hydraulic cylinder assembly, and the second opening of the third hydraulic lock is connected to port B1 of the bidirectional servo pump group through a first pipeline;

[0081] The first opening of the second balance valve is connected to port A of the hydraulic cylinder assembly, and the second opening of the second balance valve is connected to port A1 of the bidirectional servo pump group through a second pipeline;

[0082] The first port of the solenoid valve is connected to the second pipeline, and the second port of the solenoid valve is connected to the pressure oil outlet T through a third pipeline;

[0083] The fourth hydraulic lock and the fifth hydraulic lock connect the first pipeline and the second pipeline, and a make-up oil pipeline is also connected between the fourth hydraulic lock and the fifth hydraulic lock;

[0084] The first overflow valve and the second overflow valve connect the first pipeline and the second pipeline, and the third pipeline is also connected between the first overflow valve and the second overflow valve. The bidirectional servo pump group includes a servo motor and a variable piston pump, and the servo motor drives the variable piston pump to rotate forward or backward to realize the bidirectional flow of hydraulic oil.

[0085] Exemplarily, the slow-speed circuit assembly 40 is also connected to the hydraulic cylinder assembly 10 and the first hydraulic lock 20 through pipelines to form a slow-speed adjustment subsystem. It is used for the precise fine-tuning of the hydraulic cylinder. When the hydraulic cylinder needs to perform precise positioning or load control at a lower speed, the slow-speed circuit assembly adjusts by precisely supplying oil with a small flow rate to achieve smooth and precise movement.

[0086] The slow-speed circuit assembly 40 includes a third hydraulic lock 401, a fourth hydraulic lock 402, a fifth hydraulic lock 403, a second balance valve 404, a first overflow valve 405, a second overflow valve 406, a solenoid valve 407, and a bidirectional servo pump group 408.

[0087] The first opening of the third hydraulic lock 401 is connected to port B of the hydraulic cylinder assembly 10, and the second opening is connected to port B1 of the bidirectional servo pump group 408 through a first pipeline 409.

[0088] The first opening of the second balance valve 404 is connected to port A of the hydraulic cylinder assembly 10, and the second opening is connected to port A1 of the bidirectional servo pump group 408 through a second pipeline 410.

[0089] The first port of the solenoid valve 407 is connected to the second pipeline 410, and the second port is connected to the pressure oil outlet T through a third pipeline 411, and is used to release the pressure oil when necessary.

[0090] The fourth hydraulic lock 402 and the fifth hydraulic lock 403 connect the first pipeline 409 and the second pipeline 410, which are used to achieve hydraulic locking when the hydraulic cylinder stops and prevent the load from sliding down.

[0091] The oil replenishing pipeline 412 is connected between the fourth hydraulic lock 402 and the fifth hydraulic lock 403 to ensure that the system maintains sufficient oil volume during closed-loop operation and prevent oil shortage.

[0092] The first relief valve 405 and the second relief valve 406 connect the first pipeline 409 and the second pipeline 410, which are used to control the system pressure and avoid damaging the equipment due to excessive pressure. At the same time, they are also connected to the pressure oil outlet T through the third pipeline 411 to ensure the smooth return of the overflow oil.

[0093] Through the coordinated action of these components, the slow-speed circuit assembly 40 can achieve precise fine-tuning of the hydraulic cylinder, which is particularly suitable for scenarios that require high-precision positioning. Through the combined action of the fast-speed circuit assembly and the slow-speed circuit assembly, this hydraulic cylinder assembly can achieve the combination of fast approach and precise approach.

[0094] Specifically, as Figure 2 shown, this application adopts a control method combining a fast-speed circuit and a slow-speed fine-tuning circuit. The left side of the hydraulic schematic diagram is the fast-speed circuit, and the right side is the slow-speed fine-tuning circuit. The fast-speed circuit is directly controlled by the electromagnetic directional valve 301, and the slow-speed fine-tuning circuit is controlled by the micro bidirectional servo pump group 408. An internal displacement sensor 102 is installed on the hydraulic cylinder 101 to detect the position and operating speed of the hydraulic cylinder piston. The fast-speed circuit subsystem and the slow-speed circuit subsystem are not used simultaneously. When working fast, the third hydraulic lock 401 and the second balance valve 404 isolate the slow-speed circuit oil path. When working slowly, the second hydraulic lock 303 and the first balance valve 302 isolate the fast-speed circuit oil path, so as to ensure that the fast-speed circuit and the slow-speed circuit do not interfere with each other during operation.

[0095] In the fast operating condition: When the hydraulic cylinder 101 extends rapidly, the pressure oil enters the first opening of the electromagnetic directional valve 301 from the P port. The electromagnet YV2 is energized, and the spool of the electromagnetic directional valve 301 moves to the right. The first opening is communicated with the third opening, and the fourth opening is communicated with the second opening. The oil fluid enters the first balance valve 302 through the third opening of the electromagnetic directional valve 301, then enters the first hydraulic lock 20 installed on the hydraulic cylinder, and then enters the piston chamber of the hydraulic cylinder. The oil fluid in the piston rod chamber returns to the oil return port T through the second hydraulic lock 201 and the fourth opening of the electromagnetic directional valve 301. When the hydraulic cylinder retracts rapidly, the pressure oil enters the first opening of the electromagnetic directional valve 301 from the P port. The electromagnet YV1 is energized, and the spool of the electromagnetic directional valve moves to the left. The first opening is communicated with the fourth opening, and the third opening is communicated with the second opening. The oil fluid enters the piston rod chamber of the hydraulic cylinder through the fourth opening of the electromagnetic directional valve 4, then enters the second hydraulic lock 201. The oil fluid in the piston chamber returns to the oil return port T through the first hydraulic lock 20, the first balance valve 302, and the third opening of the electromagnetic directional valve.

[0096] In the slow fine-tuning operating condition: When the hydraulic cylinder extends slowly, the servo motor of the bidirectional servo pump group 408 rotates forward. The pressure oil enters the second balance valve 404 from the A1 port, passes through the first hydraulic lock 20 on the hydraulic cylinder, and enters the piston chamber of the hydraulic cylinder 101. The hydraulic oil in the piston rod chamber passes through the third hydraulic lock 401 and flows back to the B1 port of the bidirectional servo pump group 408. Due to the volume difference between the two chambers of the hydraulic cylinder, the oil fluid flowing back from the piston rod chamber is not enough to compensate for the required amount in the piston chamber. The oil fluid of the oil replenishing circuit P1 enters the B1 port of the bidirectional servo pump group through the fourth hydraulic lock 402. When the hydraulic cylinder retracts slowly, the servo motor of the bidirectional servo pump group 408 rotates in reverse. The pressure oil enters the piston rod chamber of the hydraulic cylinder 101 through the third hydraulic lock 401 from the B1 port. The hydraulic oil in the piston rod chamber passes through the second balance valve 404 and flows back to the A1 port of the bidirectional servo pump group 408. Due to the volume difference between the two chambers of the hydraulic cylinder, part of the oil fluid in the piston chamber enters the A1 port of the bidirectional servo pump, and part of the oil fluid passes through the electromagnetic valve 407 and is discharged back to the oil return port T.

[0097] In the second aspect of the present application, a control method is further proposed for the hydraulic system of the two-speed control loop in the first aspect, as Figure 3 shown, including:

[0098] S110. Obtain the current load information, current stroke information, rated load information of the hydraulic cylinder, environmental information, control mode information, and target stroke information of the above two-speed control loop hydraulic system;

[0099] Exemplarily, the system obtains the following information: current load information, current stroke information, rated load information of the hydraulic cylinder, environmental information, control mode information, and target stroke information for subsequent control decisions.

[0100] The current load information includes, but is not limited to, the actual load of the hydraulic cylinder at the current moment, which is used to determine whether it is necessary to adjust the loading speed or switch to the slow-speed circuit. The current stroke information, that is, the current position of the hydraulic cylinder, is used to judge the deviation between the current operating state and the target position. The rated load information of the hydraulic cylinder provides the maximum load capacity of the hydraulic cylinder. The environmental information includes, but is not limited to, oil temperature, ambient temperature, system pressure, etc., which is used to judge whether there are abnormal working conditions. The control mode information is the control mode selected manually, usually including accuracy priority, efficiency priority, and energy-saving priority. The system makes different control decisions according to the mode. The target stroke information is the final position that the hydraulic cylinder needs to reach, ensuring that the control target is clear.

[0101] S120. Control the working states of the fast circuit component and the slow circuit component according to the above-mentioned current load information, the above-mentioned current stroke information, the above-mentioned rated load information of the hydraulic cylinder, the above-mentioned environmental information, the above-mentioned control mode information, and the above-mentioned target stroke information.

[0102] Exemplarily, based on the above-mentioned information collected, the system controls the working states of the fast circuit component and the slow circuit component through an intelligent algorithm.

[0103] The system calculates the target stroke of the fast circuit according to the current load, stroke information, and target stroke. In the working state of the fast circuit, the system preferentially maintains a higher loading speed according to the control mode (such as efficiency priority). If it is detected that the load increases or the ambient temperature is abnormal, the system will reduce the loading speed to ensure the safety of the equipment.

[0104] When approaching the target position, the system switches to the slow circuit and sets the target stroke of the slow circuit according to the accuracy requirement. In the slow circuit, the system reduces the loading speed to ensure precise positioning of the hydraulic cylinder near the target position. If it is detected that the position error exceeds the threshold, the system makes fine adjustments by further adjusting the speed of the slow circuit.

[0105] In summary, through the high-speed operation of the fast circuit component, the execution time of the large stroke of the hydraulic cylinder is shortened. The system dynamically adjusts the switching point and loading speed of the fast and slow circuits according to different control modes and working condition requirements, realizes automatic optimization by using an intelligent algorithm, reduces manual intervention, and improves the intelligent level of control.

[0106] In a feasible implementation manner, the working state of the fast circuit component includes the target stroke of the fast circuit component and the loading speed of the fast circuit component, and the working state of the slow circuit component includes the target stroke of the slow circuit component and the loading speed of the fast circuit component;

[0107] Controlling the working states of the fast loop component and the slow loop component according to the current load information, the current stroke information, the rated load information of the hydraulic cylinder, the environmental information, the control mode information, and the target stroke information includes:

[0108] Determining the target stroke of the fast loop component and the target stroke of the slow loop component according to the current load information, the current stroke information, the rated load information of the hydraulic cylinder, the environmental information, the control mode information, and the target stroke information;

[0109] When the current working condition is that the fast loop component is working, controlling the loading speed of the fast loop component according to the current load information, the current stroke information, the control mode information, and the target stroke information;

[0110] When the current working condition is that the slow loop component is working, controlling the loading speed of the slow loop component according to the current load information, the current stroke information, the control mode information, and the target stroke information.

[0111] Exemplarily, the working states of the fast loop component include "the target stroke of the fast loop component" and "the loading speed of the fast loop component". The target stroke refers to the stroke distance that needs to be covered in the fast stage and is used for quickly approaching the target position over a large range or a long distance. The loading speed of the fast loop component refers to the operating speed adopted by the fast loop component during this target stroke.

[0112] The working states of the slow loop component include "the target stroke of the slow loop component" and "the loading speed of the slow loop component". The target stroke refers to the precise feeding or fine-tuning stroke that needs to be covered in the slow stage and is used for precise positioning or small-range adjustment. The loading speed of the slow loop component refers to the operating speed of the slow loop component during the execution of fine control.

[0113] The system makes a comprehensive judgment based on the current load information, the current stroke information, the rated load information of the hydraulic cylinder, the environmental information, the control mode information, and the target stroke information, and divides which section of the stroke is executed by the fast loop component and which section is executed by the slow loop component. For example: If the load is small and the remaining stroke is long, more is allocated to the fast loop; if the load is large or high-precision adjustment is required, the slow loop stroke is appropriately extended. According to the difference between the current position and the target stroke, it is judged whether to switch to the slow speed. Ensure that the stroke is allocated within the rated load range to avoid overload. When factors such as temperature and oil condition are not conducive to high-speed operation, appropriately shorten the fast stroke and extend the slow stroke.

[0114] The control mode information can be selected as precision - priority, efficiency - priority, or energy - saving - priority mode. Different modes will use different allocation strategies (for example, in efficiency - priority mode, it tends to have longer rapid strokes). Finally, according to the overall task requirements, the total stroke is divided into two parts: "rapid stroke + slow stroke". By synthesizing the above - mentioned information, the target stroke of the rapid - loop component and the target stroke of the slow - loop component are determined.

[0115] When the system is in the working condition of the rapid - loop component, the loading speed needs to be adjusted according to the following factors. For example: if the load suddenly increases, the loading speed can be reduced to avoid impact; if the load is small, a higher operating speed can be maintained. When approaching the starting point or the target position of the slow - loop, the system can decelerate in advance for a smooth transition. In efficiency - priority mode, a higher loading speed is encouraged to shorten the overall execution time; in precision - priority mode, deceleration is advanced when approaching the switching point to avoid overshooting the position; in energy - saving - priority mode, the speed is actively reduced under high - load or high - temperature working conditions to reduce energy consumption. Through real - time monitoring and feedback, the rapid - loop component completes most of the long - distance movements with high efficiency and switches to the slow - loop in due time before the end of the stroke.

[0116] When the system is in the working condition of the slow - loop component, high precision and system stability are mainly concerned. Therefore, the loading speed needs to be adjusted according to the following requirements. For example: if the load is close to the rated level, the speed is reduced to ensure positioning accuracy and system safety. If it is already close to the end of the target stroke, the speed is further reduced to achieve micron - level or higher precision. In precision - priority mode, the loading speed is maintained at a low level to minimize the position error; in efficiency - priority mode, the speed is slightly increased on the premise of ensuring precision to improve the cycle time; in energy - saving - priority mode, the speed is actively reduced under continuous high - load or high - ambient - temperature conditions. The slow - loop is usually the last part of the stroke, and the system performs fine - tuning in segments according to the pre - divided slow - target stroke. With the help of the slow - loop component, the hydraulic cylinder can achieve precise positioning or flexible adjustment within a small range in the final stroke stage.

[0117] In a feasible implementation manner, determining the target stroke of the rapid - loop component and the target stroke of the slow - loop component according to the above - mentioned current load information, the above - mentioned current stroke information, the above - mentioned rated load information of the hydraulic cylinder, the above - mentioned environmental information, the above - mentioned control mode information, and the above - mentioned target stroke information includes:

[0118] Constructing a feature vector according to the above - mentioned current load information, the above - mentioned current stroke information, the above - mentioned rated load information of the hydraulic cylinder, the above - mentioned environmental information, and the above - mentioned target stroke information;

[0119] Defining a state space according to the above - mentioned feature vector;

[0120] Establishing a reinforcement - learning action according to the rapid - adjustment ratio and the slow - adjustment ratio;

[0121] Determine the reward function according to the above control mode, where the above reward function includes a positioning accuracy term, a time efficiency term, and an energy consumption term;

[0122] Establish a reinforcement learning model based on the above state space, the above reinforcement learning actions, and the above reward function to obtain the initial ratio of fast adjustment and slow adjustment;

[0123] Determine the adjustment ratios of fast adjustment and slow adjustment according to the above current load information, the above current travel information, the above target travel information, and the fuzzy rule base;

[0124] Determine the target travel of the above fast loop component and the target travel of the above slow loop component according to the above initial ratio of fast adjustment and slow adjustment and the adjustment ratios of fast adjustment and slow adjustment.

[0125] Exemplarily, this embodiment provides a method for determining the target travels of the fast loop component and the slow loop component of a hydraulic system based on reinforcement learning and fuzzy control. By comprehensively considering the current load information, the current travel information, the rated load information of the hydraulic cylinder, the environmental information, the control mode information, and the target travel information, the target travels of the fast loop and the slow loop are intelligently determined to achieve precise control of the hydraulic system.

[0126] Construct a feature vector according to the current load information, the current travel information, the rated load information of the hydraulic cylinder, the environmental information, and the target travel information , and use the feature vector to represent the current state of the hydraulic system:

[0127]

[0128] is the current load information, is the current travel position, is the target travel position information, is the rated load information of the hydraulic cylinder, includes environmental temperature information.

[0129] Divide the state space of the hydraulic system according to the feature vector : :

[0130]

[0131] The state space is used to characterize the specific state of the hydraulic system under different operating conditions.

[0132] Based on the adjustment ratios of the fast loop and the slow loop, establish the action space of reinforcement learning :

[0133]

[0134] For rapid ratio adjustment, For slow ratio adjustment, The sum of the rapid and slow adjustment ratios is 1 to ensure reasonable task allocation.

[0135] Define different reward functions according to the control mode (precision priority, efficiency priority, or energy conservation priority). . The reward function consists of the following three parts:

[0136] 1. Positioning accuracy term

[0137]

[0138] is the precision penalty coefficient.

[0139] 2. Time efficiency term

[0140]

[0141] is the time penalty coefficient, is the time to reach the target travel.

[0142] 3. Energy consumption term

[0143]

[0144] is the energy consumption penalty coefficient, is the current load information, is the current speed information.

[0145] According to the control mode, different weighted combinations are used to form the final reward function:

[0146]

[0147] For example:

[0148] Precision priority mode:

[0149] Efficiency priority mode:

[0150] Energy conservation priority mode:

[0151] Based on the state space , the action space and the reward function , a reinforcement learning model is established using a reinforcement learning algorithm (such as deep reinforcement learning DDPG or Q-Learning).

[0152] The reinforcement learning objective is to maximize the cumulative reward function :

[0153]

[0154] is the policy function, is the discount factor, is the total number of time steps

[0155] By training the reinforcement learning model, the initial ratio of fast adjustment and slow adjustment is obtained :

[0156]

[0157] Among them, is the cumulative reward function, which measures the expected total reward obtained by the agent over the entire time period under the policy . represents the mathematical expectation of the reward under the policy . is the policy function, which represents the rule for the agent to select actions in the state space . is the discount factor, with a range of , which is used to balance the importance of current rewards and future rewards. A lower value focuses more on short-term rewards, while a higher value pays more attention to long-term returns. is the immediate reward obtained at the th moment, which represents the gain obtained after performing a specific action in a certain state. is the total number of time steps, which represents the maximum number of time steps in the reinforcement learning process.

[0158] To further optimize the initial ratio, based on the actual working condition changes, a fuzzy rule base is used for adjustment. The fuzzy inputs are the current load change rate and the current stroke error. The current load change rate , where is the current load, is the load at the previous moment, is the rated load. The current stroke error , and the fuzzy outputs are the fast adjustment amount and the slow adjustment amount .

[0159] The fuzzy rules can include but are not limited to:

[0160] 1. If increases and decreases, the fast adjustment ratio is decreased and the slow adjustment ratio is increased.

[0161] 2. If decreases and increases, the fast adjustment ratio is increased and the slow adjustment ratio is decreased.

[0162] Calculate the final adjustment ratio according to the fuzzy rule base:

[0163]

[0164] Finally, determine the target strokes of the fast loop component and the slow loop component according to the ratios of fast and slow adjustments:

[0165]

[0166] wherein, is the target stroke of the fast loop component, is the target stroke of the slow loop component.

[0167] This embodiment provides a method for controlling the target stroke of a hydraulic system based on reinforcement learning and fuzzy control. The hydraulic system can adaptively adjust the loading speed under different working conditions and control modes to achieve comprehensive optimization of precision, efficiency, and energy conservation.

[0168] In a feasible embodiment, controlling the loading speed of the fast loop component according to the current load information, the current stroke information, the control mode information, and the target stroke information includes:

[0169] Determine a dynamic coefficient according to the current load information, the current stroke information, the control mode information, and the target stroke information;

[0170] Construct an adaptive PID control model according to the dynamic coefficient;

[0171] Control the loading speed of the fast loop component based on the adaptive PID control model.

[0172] Exemplarily, in the control of the loading speed of the fast loop component, the dynamic coefficient is used to adjust the proportional, integral, and derivative parameters of the PID controller to adapt to different working conditions and control modes.

[0173] Determine the dynamic coefficient according to the current load information, the current stroke information, the control mode information, and the target stroke information. The current load information reflects the real-time load of the hydraulic cylinder and affects the control strength of the loading speed. The current stroke information Indicates the current position of the hydraulic cylinder and is used to judge the distance from the target stroke. Control mode information Includes precision priority, efficiency priority, or energy conservation priority, which affects the weight distribution of the dynamic coefficient. Target stroke information Is the target position of the hydraulic cylinder and provides the basis for adjusting the acceleration.

[0174] The calculation formula of the dynamic coefficient includes:

[0175] 1. Proportional coefficient :

[0176] Adjust the proportional coefficient according to the comprehensive judgment of load and position error:

[0177]

[0178] Among them, Is the initial proportional coefficient, Is the position error adjustment coefficient, Is the load adjustment coefficient, Is the rated load of the hydraulic cylinder.

[0179] 2. Integral coefficient :

[0180] When the position error is small, accelerate the response speed of the integral term to reduce the steady-state error:

[0181]

[0182] Among them, Is the initial integral coefficient, Is the position error adjustment coefficient, Is the load adjustment coefficient.

[0183] 3. Differential coefficient :

[0184] When the load changes violently, increase the weight of the differential term to suppress oscillation:

[0185]

[0186] Among them, Is the initial differential coefficient, Is the load change adjustment coefficient

[0187] To ensure the stability and safety of the system, the loading speed also needs to meet the following limiting conditions:

[0188] 1. Maximum speed limit

[0189]

[0190] 2. Minimum speed limit

[0191]

[0192] 3. Acceleration smoothness

[0193]

[0194] is the maximum acceleration allowed by the system.

[0195] According to different control modes, the parameters of the adaptive PID control model will be adjusted. Specifically, see Table 1 below:

[0196] Table 1

[0197]

[0198] In the accuracy - priority mode, the position error is minimized first, emphasizing the roles of the proportional and integral terms. In the efficiency - priority mode, the response speed is increased, and the derivative term is appropriately increased to reduce overshoot. In the energy - saving - priority mode, unnecessary acceleration changes are reduced, and the regulation mainly relies on the derivative term. Through this method, the hydraulic system can control the fast - loop components to achieve precise loading - speed control under different working conditions, meeting different requirements for accuracy, efficiency, and energy saving.

[0199] In a feasible implementation, controlling the loading speed of the slow - speed loop component according to the above - mentioned current load information, the above - mentioned current stroke information, the above - mentioned control - mode information, and the target - stroke information includes:

[0200] Determining an objective function according to the above - mentioned current load information, the above - mentioned current stroke information, the above - mentioned control - mode information, and the target - stroke information, where the objective function includes a position - error term, a speed - smoothness term, an acceleration - smoothness term, and a load - adaptability term;

[0201] Determining the weight coefficients of the objective function according to the above - mentioned control - mode information;

[0202] Controlling the loading speed of the slow - speed loop component according to the objective function and the quadratic - programming method.

[0203] Exemplarily, the objective function includes four types of sub - objective terms: a position - error term, a speed - smoothness term, an acceleration - smoothness term, and a load - adaptability term, and its mathematical form is as follows:

[0204]

[0205] Among them, is the weight coefficient of the objective function, dynamically set according to the control mode; is the position - error term; is the velocity stability term; is the acceleration smoothness term; is the load adaptability item.

[0206] Position error term for:

[0207]

[0208] in, is the target location information, It is the current location information.

[0209] The position error term is used to penalize the error between the current stroke and the target stroke. The fourth power form intensifies the penalty for large errors and smoothes the response to small errors, which is helpful for precision control.

[0210] Speed ​​stability for:

[0211]

[0212] in, is the current speed information, It is the speed information of the next moment.

[0213] The speed smoothness term controls the smoothness of speed changes and suppresses mutations. The exponential form is used to quickly amplify the impact of speed mutations, which helps to achieve smooth acceleration during efficiency control.

[0214] Acceleration smoothness term for:

[0215]

[0216] in, is the current acceleration information, is the acceleration information at the next moment, is the linear adjustment coefficient, is the secondary adjustment coefficient.

[0217] The acceleration smoothness term is used to limit the fluctuation of loading acceleration, and the linear term Ensure sensitive response to small changes, quadratic term Suppress drastic jumps and enhance system stability.

[0218] Load adaptability item for:

[0219]

[0220] in, is the current load information, is the load information for the next moment, is the rated load information, is the load change adjustment coefficient, is the current speed information.

[0221] The load adaptability term is used to suppress high-speed operation under high-load or load mutation conditions, dynamically adapt to load changes, reduce energy consumption, and improve energy-saving and equipment protection capabilities.

[0222] To optimize the loading speed , the constructed objective function is used as the cost function to construct the following quadratic programming problem:

[0223]

[0224] where, is the loading speed for the next moment, is the objective function.

[0225] The constraint conditions are:

[0226] Speed constraint:

[0227]

[0228] where, is the minimum loading speed allowed by the system, is the maximum loading speed allowed by the system.

[0229] Acceleration constraint:

[0230]

[0231] is the maximum allowable loading acceleration, is the control period.

[0232] Stroke limit (to prevent overrun):

[0233]

[0234] Using a standard quadratic programming (QuadraticProgramming, QP) solver, the optimal loading speed that satisfies the constraint conditions can be obtained . The solved will be used as the loading speed command for the next control period and applied to the slow-speed loop component. At the same time, the system can collect feedback in real time (such as position, speed, load, etc.) and reconstruct the objective function to form a closed-loop control strategy.

[0235] In a feasible implementation, it further includes:

[0236] When the current working condition is that the above-mentioned fast loop component is working and the above-mentioned environmental information exceeds the preset environmental threshold for the first duration, reduce the loading speed of the above-mentioned fast loop component and generate a first warning message;

[0237] After reducing the loading speed of the above-mentioned fast loop component for the second duration, when the above-mentioned environmental information still exceeds the preset environmental threshold, switch to the slow loop component loading mode and generate a second warning message.

[0238] In a feasible implementation manner, it further includes:

[0239] After running for the third duration in the above-mentioned slow loop component loading mode, when the above-mentioned environmental information still exceeds the preset environmental threshold, pause the loading and generate a third warning message, where the above-mentioned first duration, the above-mentioned second duration, and the above-mentioned third duration are determined according to the abnormal degree of the environmental information. The above-mentioned first duration is used to judge the temporary loading speed adjustment time of the fast loop component, the above-mentioned second duration is used for the switching time when the abnormality has not recovered, and the above-mentioned third duration is used for the pause loading time when the slow loop component still cannot return to normal.

[0240] Exemplarily, the first stage: When the current working condition is the fast loop component working mode and it is detected that the environmental information exceeds the preset environmental threshold and continues to exceed the first duration, the system performs the operation of reducing the loading speed of the fast loop component. Specifically:

[0241] According to the preset loading speed adjustment coefficient , reduce the loading speed of the fast loop component.

[0242]

[0243] Among them, is the original loading speed of the fast loop component; is the adjusted loading speed of the fast loop component; is the speed reduction coefficient.

[0244] While reducing the loading speed, the system generates a first warning message to notify the operator that the current environmental information is abnormal and prompts to check the equipment operation status. The first warning message can be: The environmental information exceeds the preset threshold, the loading speed of the fast loop component has been reduced, please check the equipment status.

[0245] Second stage: After the fast loop component reduces the loading speed, if the environmental information still exceeds the preset threshold and has continued for more than the second duration, the system performs the following operations: 1. Switch to the slow loop component loading mode. The system stops the operation of the fast loop component and switches to the slow loop component loading mode to reduce the overall load and operating temperature of the hydraulic system. 2. Generate a second warning message. The system generates a second warning message to remind the operator that the system has now switched to the slow loading mode. The second warning message can be: The environmental information remains abnormal, and the system has switched to the slow loop component loading mode to protect the equipment.

[0246] Third stage: After operating in the slow loop component loading mode, if the environmental information still exceeds the preset threshold and has continued for more than the third duration, the system performs the following operations: 1. The system pauses the loading action of the hydraulic cylinder to prevent the equipment from being further damaged due to environmental deterioration.

[0247]

[0248] 2. While the loading is paused, the system generates a third warning message to prompt the operator that the environment is extremely abnormal and immediate inspection and maintenance measures need to be taken. The third warning message can be: The environmental information remains abnormal, and the system has paused the loading. Please immediately check the equipment and perform maintenance.

[0249] In this embodiment, through real-time monitoring of environmental information and adopting a phased adjustment strategy, while ensuring the stable operation of the hydraulic system, when the environment is abnormal, the loading speed is timely reduced or switched to the slow loading mode to avoid equipment overload or overheating. Through phased warning messages to notify the operator, the abnormal condition of the equipment is timely reminded, facilitating a rapid response. After the environmental information returns to normal, the loading speed can be quickly restored, reducing production losses caused by downtime. By reducing the loading speed and switching to the slow mode, energy consumption is effectively reduced, and the service life of the equipment is extended.

[0250] The above embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present application.

Claims

1. A dual-speed control circuit hydraulic system, characterized in that: include: A hydraulic cylinder assembly, the hydraulic cylinder assembly comprising a hydraulic cylinder and a displacement sensor; First hydraulic lock; A fast loop assembly, wherein the fast loop assembly, the first hydraulic lock and the hydraulic cylinder assembly are connected through pipelines to form a fast adjustment subsystem; A slow speed circuit assembly, wherein the slow speed circuit assembly, the first hydraulic lock and the hydraulic cylinder assembly are connected to form a slow speed adjustment subsystem; The fast circuit assembly includes a solenoid reversing valve, a first balancing valve and a second hydraulic lock; The first opening of the electromagnetic reversing valve is connected to the pressure oil inlet P, the second opening of the electromagnetic reversing valve is connected to the pressure oil outlet T, the third outlet of the electromagnetic reversing valve is connected to the first opening of the first balancing valve, the second opening of the first balancing valve is connected to the A port of the hydraulic cylinder assembly, and the second hydraulic lock is connected to the B port of the hydraulic cylinder assembly and the fourth opening of the electromagnetic reversing valve; The slow circuit assembly includes a third hydraulic lock, a fourth hydraulic lock, a fifth hydraulic lock, a second balancing valve, a first overflow valve, a second overflow valve, a solenoid valve and a bidirectional servo pump group; The first opening of the third hydraulic lock is connected to the B port of the hydraulic cylinder assembly, and the second opening of the third hydraulic lock is connected to the B1 port of the bidirectional servo pump assembly through the first pipeline; The first opening of the second balancing valve is connected to the A port of the hydraulic cylinder assembly, and the second opening of the second balancing valve is connected to the A1 port of the bidirectional servo pump assembly through a second pipeline; The first port of the solenoid valve is connected to the second pipeline, and the second port of the solenoid valve is connected to the pressure oil outlet T through a third pipeline; The fourth hydraulic lock and the fifth hydraulic lock are connected to the first pipeline and the second pipeline, and the fourth hydraulic lock and the fifth hydraulic lock are also connected to an oil replenishment pipeline; The first overflow valve and the second overflow valve are connected to the first pipeline and the second pipeline, and the third pipeline is also connected between the first overflow valve and the second overflow valve. The bidirectional servo pump group includes a servo motor and a variable piston pump. The servo motor drives the variable piston pump to rotate forward or reverse to realize bidirectional flow of hydraulic oil.

2. A control method for the dual-speed control circuit hydraulic system according to claim 1, characterized in that: include: Acquiring current load information, current stroke information, hydraulic cylinder rated load information, environmental information, control mode information and target stroke information of the dual-speed control loop hydraulic system; The working states of the fast loop component and the slow loop component are controlled according to the current load information, the current stroke information, the hydraulic cylinder rated load information, the environmental information, the control mode information and the target stroke information.

3. The control method according to claim 2, characterized in that: The working state of the fast loop assembly includes a target stroke of the fast loop assembly and a loading speed of the fast loop assembly, and the working state of the slow loop assembly includes a target stroke of the slow loop assembly and a loading speed of the fast loop assembly; The controlling the working states of the fast loop component and the slow loop component according to the current load information, the current stroke information, the rated load information of the hydraulic cylinder, the environmental information, the control mode information and the target stroke information includes: Determine the target stroke of the fast circuit component and the target stroke of the slow circuit component according to the current load information, the current stroke information, the hydraulic cylinder rated load information, the environmental information, the control mode information and the target stroke information; When the current working condition is that the fast loop assembly is working, controlling the loading speed of the fast loop assembly according to the current load information, the current stroke information, the control mode information and the target stroke information; When the current working condition is that the slow loop component is working, the loading speed of the slow loop component is controlled according to the current load information, the current stroke information, the control mode information and the target stroke information.

4. The control method according to claim 3, characterized in that: The determining the target stroke of the fast circuit component and the target stroke of the slow circuit component according to the current load information, the current stroke information, the rated load information of the hydraulic cylinder, the environmental information, the control mode information and the target stroke information comprises: constructing a feature vector according to the current load information, the current stroke information, the hydraulic cylinder rated load information, the environmental information and the target stroke information; defining a state space according to the feature vector; Establish reinforcement learning actions based on fast adjustment ratio and slow adjustment ratio; Determining a reward function according to the control mode, wherein the reward function includes a positioning accuracy term, a time efficiency term, and an energy consumption term; Establishing a reinforcement learning model according to the state space, the reinforcement learning action and the reward function to obtain initial proportions of fast adjustment and slow adjustment; Determine the adjustment ratio of fast regulation and slow regulation according to the current load information, the current travel information, the target travel information and a fuzzy rule base; The target stroke of the fast loop component and the target stroke of the slow loop component are determined according to the initial ratio of the fast adjustment and the slow adjustment and the adjustment ratio of the fast adjustment and the slow adjustment.

5. The control method according to claim 3, characterized in that: The controlling the loading speed of the fast loop assembly according to the current load information, the current stroke information, the control mode information and the target stroke information comprises: determining a dynamic coefficient according to the current load information, the current stroke information, the control mode information and the target stroke information; Constructing an adaptive PID control model according to the dynamic coefficients; The loading speed of the fast loop component is controlled based on the adaptive PID control model.

6. The control method according to claim 3, characterized in that: The controlling the loading speed of the slow loop component according to the current load information, the current stroke information, the control mode information and the target stroke information comprises: Determining an objective function according to the current load information, the current stroke information, the control mode information and the target stroke information, wherein the objective function includes a position error term, a speed smoothness term, an acceleration smoothness term and a load adaptability term; Determining a weight coefficient of the objective function according to the control mode information; The loading speed of the slow loop component is controlled according to the objective function and the quadratic programming method.

7. The control method according to claim 3, characterized in that: Also includes: When the current working condition is that the fast loop component is working and the environmental information exceeds the preset environmental threshold for a first time period, reducing the loading speed of the fast loop component and generating a first warning information; After reducing the loading speed of the fast loop component for a second period of time, if the environmental information still exceeds the preset environmental threshold, switch to the slow loop component loading mode and generate a second warning information, wherein the first period of time and the second period of time are determined according to the abnormality degree of the environmental information, the first period of time is used to determine the temporary loading speed adjustment time of the fast loop component, and the second period of time is used for the switching time when the abnormality has not been restored.

8. The control method according to claim 7, characterized in that: Also includes: After the slow loop component runs for a third period of time in the loading mode, if the environmental information still exceeds the preset environmental threshold, loading is suspended and a third warning information is generated, wherein the third period of time is determined based on the degree of abnormality of the environmental information, and the third period of time is used to suspend loading when the slow loop component still cannot return to normal.

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