Hydraulic transmission mechanism control method, device, system and storage medium

Abstract

The application discloses a hydraulic transmission mechanism control method, device, system and storage medium, relates to the technical field of hydraulic transmission, and comprises the following steps: acquiring real-time instantaneous displacement of a hydraulic pump in a hydraulic transmission mechanism and real-time pipeline oil pressure of a hydraulic pipeline; the real-time instantaneous displacement is determined according to real-time input oil pressure of the hydraulic transmission mechanism and historical pipeline oil pressure of the hydraulic pipeline; the real-time oil leakage amount of the hydraulic pipeline is determined according to the real-time instantaneous displacement and the real-time pipeline oil pressure; the speed adjustment value of a motor in the hydraulic transmission mechanism is determined according to the real-time oil leakage amount; and the real-time speed of the motor is adjusted according to the speed adjustment value, so as to adjust the real-time pipeline oil pressure. The application directly adjusts the real-time pipeline oil pressure according to the oil leakage amount, the adjustment amount of the pipeline oil pressure is not influenced by the gain parameter of a PI control loop before the hydraulic pump in the hydraulic transmission mechanism, the technical problem of low control precision of an existing hydraulic transmission mechanism is solved, and the control precision of the hydraulic transmission control mechanism is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hydraulic transmission, and particularly relates to a hydraulic transmission mechanism control method, device, system and storage medium. BACKGROUND

[0002] In hydraulic equipment such as vertical injection molding machines and machine tool hydraulic stations, a hydraulic transmission system is usually used to provide power for various actions required in the process. The size of the fluctuation of the pipeline oil pressure of the hydraulic pipeline in the hydraulic transmission system is a core index of the hydraulic transmission system.

[0003] In the hydraulic transmission system, the hydraulic transmission mechanism is controlled by a PI (Proportional Integral) control mode to realize the adjustment of the fluctuation size of the pipeline oil pressure. However, when the hydraulic pipeline of the hydraulic transmission mechanism is short, too strong loop gain parameters of the PI control will cause pipeline oil pressure oscillation, resulting in low control precision. SUMMARY

[0004] The main purpose of the present application is to provide a hydraulic transmission mechanism control method, device, system and storage medium, which aims to solve the technical problem of low control precision of the existing hydraulic transmission mechanism.

[0005] To achieve the above purpose, the present application adopts the following technical solutions:

[0006] In a first aspect, the present application provides a hydraulic transmission mechanism control method, which comprises:

[0007] acquiring a real-time instantaneous displacement of a hydraulic pump in the hydraulic transmission mechanism and a real-time pipeline oil pressure of a hydraulic pipeline; the real-time instantaneous displacement is determined according to a real-time input oil pressure of the hydraulic transmission mechanism and a historical pipeline oil pressure of the hydraulic pipeline;

[0008] determining a real-time oil leakage amount of the hydraulic pipeline according to the real-time instantaneous displacement and the real-time pipeline oil pressure;

[0009] determining a speed adjustment value of a motor in the hydraulic transmission mechanism according to the real-time oil leakage amount;

[0010] adjusting a real-time speed of the motor according to the speed adjustment value to adjust the real-time pipeline oil pressure.

[0011] Optionally, the step of determining the real-time oil leakage amount of the hydraulic pipeline according to the real-time instantaneous displacement and the real-time pipeline oil pressure comprises:

[0012] acquiring a relationship function between the oil leakage amount and the instantaneous displacement and the pipeline oil pressure;

[0013] determining the real-time oil leakage amount according to the relationship function, the real-time instantaneous displacement and the real-time pipeline oil pressure.

[0014] Optionally, after the step of obtaining the relationship function between the oil leakage amount and the instantaneous displacement and the pipeline oil pressure, the method further comprises:

[0015] Discretizing the relationship function to obtain a discretized control equation;

[0016] According to the relationship function, the real-time instantaneous displacement and the real-time pipeline oil pressure, determining the real-time oil leakage amount comprises:

[0017] According to the control equation, the real-time instantaneous displacement and the real-time pipeline oil pressure, determining the real-time oil leakage amount.

[0018] Optionally, the step of obtaining the relationship function between the oil leakage amount and the instantaneous displacement and the pipeline oil pressure comprises:

[0019] Obtaining a transfer function between the input oil pressure and the pipeline oil pressure;

[0020] Transforming the transfer function with the oil leakage amount as input and the instantaneous displacement and the pipeline oil pressure as output to obtain the relationship function.

[0021] Optionally, the step of obtaining the transfer function between the input oil pressure and the pipeline oil pressure comprises:

[0022] Obtaining an oil pressure change curve of the hydraulic transmission mechanism under an input pressure function test;

[0023] Data fitting the oil pressure change curve to obtain an oil pressure change function;

[0024] Obtaining the transfer function according to the input pressure function and the oil pressure change function.

[0025] Optionally, the step of data fitting the oil pressure change curve to obtain the oil pressure change function comprises:

[0026] Discretizing the oil pressure change curve to obtain a plurality of discrete pressure data;

[0027] Data fitting the plurality of discrete pressure data to obtain the oil pressure change function.

[0028] Optionally, the input pressure function is a pressure step function comprising a plurality of input pressures.

[0029] In a second aspect, the application further provides a hydraulic transmission mechanism control device, the device comprising: a memory, a processor, and a hydraulic transmission mechanism control program stored on the memory and executable on the processor, configured to implement the steps of any of the above hydraulic transmission mechanism control methods through the hydraulic transmission mechanism control program.

[0030] In a second aspect, the application further provides a hydraulic transmission mechanism control system, the system comprising:

[0031] The hydraulic transmission mechanism comprises a connected motor, a hydraulic pump and a hydraulic pipeline.

[0032] The hydraulic transmission mechanism control device as described above;

[0033] The hydraulic transmission mechanism control device is connected with the motor.

[0034] In a fourth aspect, the present application further provides a computer readable storage medium, and the computer readable storage medium stores a computer program, and the computer program is executed by a processor to implement the steps of the hydraulic transmission mechanism control method according to any one of the above.

[0035] The present application provides a hydraulic transmission mechanism control method, device, system and storage medium, obtaining real-time instantaneous displacement of a hydraulic pump in a hydraulic transmission mechanism and real-time pipeline oil pressure of a hydraulic pipeline; the real-time instantaneous displacement is determined according to real-time input oil pressure of the hydraulic transmission mechanism and historical pipeline oil pressure of the hydraulic pipeline; real-time oil leakage of the hydraulic pipeline is determined according to the real-time instantaneous displacement and the real-time pipeline oil pressure; a speed adjustment value of a motor in the hydraulic transmission mechanism is determined according to the real-time oil leakage; and real-time speed of the motor is adjusted according to the speed adjustment value to adjust the real-time pipeline oil pressure.

[0036] Therefore, according to the real-time instantaneous displacement of the hydraulic pump and the real-time pipeline oil pressure of the hydraulic pipeline, the present application determines the real-time oil leakage of the hydraulic pipeline, determines the speed adjustment value of the motor through the real-time oil leakage, and adjusts the speed of the motor through the speed adjustment value to adjust the real-time pipeline oil pressure, so as to directly adjust the real-time pipeline oil pressure according to the oil leakage of the hydraulic pipeline, avoid the pipeline oil pressure from fluctuating too much, and avoid the adjustment amount of the pipeline oil pressure from being affected by the gain parameter of the PI control loop before the hydraulic pump in the hydraulic transmission mechanism, so as to have high control precision. BRIEF DESCRIPTION OF DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of the drawings shown.

[0038] Figure 1 The hydraulic transmission mechanism control device of the hardware running environment related to the embodiment of the present application is shown in the structural diagram.

[0039] Figure 2 The flowchart of the hydraulic transmission mechanism control method provided by the embodiment of the present application is shown in the flowchart.

[0040] Figure 3 A control block diagram of an exemplary existing hydraulic transmission mechanism;

[0041] Figure 4 A transfer function block diagram of the hydraulic transmission mechanism shown in Figure 3

[0042] Figure 5 A control block diagram of a hydraulic transmission mechanism control method provided by an embodiment of the present application.

[0043] The implementation, functional features and advantages of the present application will be further described with reference to the accompanying drawings in conjunction with the embodiments. DETAILED DESCRIPTION

[0044] In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0045] It should be understood that the specific embodiments described herein are merely used to explain the present application, and are not used to limit the present application.

[0046] In the present application, the term "comprising", "containing" or any other variant thereof is intended to cover the non-exclusive inclusion, so that the device or system including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or includes elements inherent to such device or system. Without more limitations, the elements defined by the statement "comprising" do not exclude the presence of other identical elements in the device or system including the element.

[0047] In hydraulic equipment such as vertical injection molding machines and machine tool hydraulic stations, a hydraulic transmission system is usually used to provide power for various actions required by the process and to meet the related indicators such as pressure, speed and temperature required by each part of the hydraulic equipment. The hydraulic equipment is mainly composed of various hydraulic elements and hydraulic auxiliary elements. The oil pump and the motor are the power source of the hydraulic equipment, and various valves control the oil pressure and flow to meet the various requirements of the hydraulic equipment process.

[0048] ​In vertical injection molding machines, the oil line between the cylinder and the oil pump is typically short (less than 1m). Under pressure-maintaining conditions, due to the short length of the oil line and the limited oil volume within it, even small changes in oil volume can cause pressure fluctuations. Therefore, the pressure indicator for short oil lines is more sensitive to flow fluctuations within the line. Furthermore, the gear pump, which serves as the power unit, has regular internal leakage, which can also cause flow variations within the oil line and result in pressure fluctuations. The magnitude of pressure fluctuation is a core indicator for evaluating the performance of hydraulic equipment and is also one of the core indicators of electro-hydraulic drives. Therefore, achieving high-precision pressure maintenance for hydraulic equipment with short oil lines has become a challenge under current control solutions.

[0049] In related technologies, PI (Proportional Integral) control is used to control hydraulic transmission mechanisms to adjust the fluctuation of pipeline oil pressure. However, when the hydraulic pipeline of the hydraulic transmission mechanism is short, excessively strong PI control loop gain parameters can cause pipeline oil pressure fluctuations, resulting in low control accuracy.

[0050] In view of the technical problem of low control accuracy of existing hydraulic transmission mechanisms, this application provides a hydraulic transmission mechanism control method. The overall idea is as follows:

[0051] The method includes: obtaining the real-time instantaneous displacement of a hydraulic pump in a hydraulic transmission mechanism and the real-time pipeline oil pressure of a hydraulic pipeline; determining the real-time instantaneous displacement according to the real-time input oil pressure of the hydraulic transmission mechanism and the historical pipeline oil pressure of the hydraulic pipeline; determining the real-time oil leakage of the hydraulic pipeline according to the real-time instantaneous displacement and the real-time pipeline oil pressure; determining the speed adjustment value of a motor in the hydraulic transmission mechanism according to the real-time oil leakage; and adjusting the real-time speed of the motor according to the speed adjustment value to adjust the real-time pipeline oil pressure.

[0052] The present application provides a hydraulic transmission mechanism control method, which determines the real-time oil leakage amount of the hydraulic pipeline according to the real-time instantaneous displacement of the hydraulic pump and the real-time pipeline oil pressure of the hydraulic pipeline, determines the speed adjustment value of the motor according to the real-time oil leakage amount, and then adjusts the speed of the motor according to the speed adjustment value to adjust the real-time pipeline oil pressure, thereby directly adjusting the real-time pipeline oil pressure according to the oil leakage amount of the hydraulic pipeline, avoiding excessive fluctuations in the pipeline oil pressure. When adjusting the pipeline oil pressure, the adjustment amount of the pipeline oil pressure is not affected by the gain parameter of the PI control loop before the hydraulic pump in the hydraulic transmission mechanism, and the control accuracy is relatively high.

[0053] The following is a detailed description of the hydraulic transmission mechanism control method, device, system and storage medium used in the technical implementation of this application:

[0054] This embodiment provides a hydraulic transmission mechanism control system, which may include:

[0055] A hydraulic transmission mechanism, which includes a connected motor, a hydraulic pump, and hydraulic pipelines;

[0056] Hydraulic transmission mechanism control equipment;

[0057] The hydraulic transmission mechanism control device is connected to the motor.

[0058] In a hydraulic transmission mechanism control system, the instantaneous displacement of the hydraulic pump can be controlled by controlling the speed of the motor, thereby controlling the oil pressure in the hydraulic pipeline. The hydraulic transmission mechanism control device may include a controller and / or a driver, which may be an electro-hydraulic driver.

[0059] Among them, reference Figure 1 , Figure 1 This is a structural diagram of the hydraulic transmission mechanism control device in the hardware operating environment involved in the embodiment of the present application.

[0060] like Figure 1 As shown, the device may include: a processor 1001, such as a CPU, a user interface 1003, a memory 1005, and a communication bus 1002. The communication bus 1002 is used to realize the connection and communication between these components. The user interface 1003 may include a motor, and optionally the user interface 1003 may also be a display screen (Display), an input unit such as a keyboard (Keyboard), etc. The memory 1005 may be a high-speed RAM memory, or a stable memory (non-volatile memory), such as a disk memory. The memory 1005 may also be a storage device independent of the aforementioned processor 1001.

[0061] It is understood that the device may further include a network interface 1004, which may optionally include a standard wired interface or a wireless interface (such as a WI-FI interface). Optionally, the device may further include an RF (Radio Frequency) circuit, a sensor, an audio circuit, a WiFi module, and the like.

[0062] Those skilled in the art will understand that Figure 1 The device structure shown in the figure does not constitute a limitation of the device, and may include more or fewer components than shown in the figure, or combine certain components, or arrange the components differently.

[0063] The hydraulic transmission mechanism control method and storage medium of the present application are described in detail below with reference to the accompanying drawings and specific implementation plans.

[0064] Based on the above hardware structure but not limited to the above hardware structure, refer to Figures 2 to 5 , Figure 2A flowchart of a hydraulic transmission mechanism control method provided by an embodiment of the present application is shown in the figure, Figure 3 A control block diagram of an exemplary existing hydraulic transmission mechanism is shown in the figure, Figure 4 A control block diagram of an exemplary existing hydraulic transmission mechanism is shown in the figure, Figure 3 A transfer function block diagram of the hydraulic transmission mechanism is shown in the figure, Figure 5 A control block diagram of a hydraulic transmission mechanism control method provided by an embodiment of the present application is shown in the figure.

[0065] The embodiment provides a hydraulic transmission mechanism control method, which can include the following steps as shown in the figure, Figure 2 The method can include the following steps as shown in the figure,

[0066] Step S100: Real-time instantaneous displacement of a hydraulic pump in a hydraulic transmission mechanism and real-time pipeline oil pressure of a hydraulic pipeline are obtained.

[0067] The real-time instantaneous displacement is determined according to real-time input oil pressure of the hydraulic transmission mechanism and historical pipeline oil pressure of the hydraulic pipeline.

[0068] Step S200: Real-time oil leakage of the hydraulic pipeline is determined according to the real-time instantaneous displacement and the real-time pipeline oil pressure.

[0069] Step S300: A speed adjustment value of a motor in the hydraulic transmission mechanism is determined according to the real-time oil leakage.

[0070] Step S400: Real-time speed of the motor is adjusted according to the speed adjustment value, so as to adjust the real-time pipeline oil pressure.

[0071] In the embodiment, the execution subject can be the hydraulic transmission mechanism control device.

[0072] Taking hydraulic transmission mechanism control of a vertical injection molding machine as an example, the hydraulic pipeline between the hydraulic pump and the oil cylinder in the hydraulic transmission mechanism is relatively short (usually less than 1 m), and the gear pump as a power unit in the hydraulic transmission mechanism has regular internal leakage, which can cause flow change in the hydraulic pipeline, cause pipeline oil pressure fluctuation, and affect the effect of the injection molding machine. In particular, in the pressure maintaining stage of the vertical injection molding machine, the pipeline oil pressure has a greater impact on the pressure maintaining effect. Therefore, the pipeline oil pressure of the hydraulic pipeline is not only affected by the instantaneous displacement of the hydraulic pump, but also affected by the oil leakage of the hydraulic pipeline. Therefore, by determining the real-time oil leakage to adjust the speed of the motor, the pipeline oil pressure can be accurately adjusted, and the pipeline oil pressure fluctuation caused by oil leakage can be avoided.

[0073] As shown in the figure, Figure 3 The hydraulic transmission mechanism control process can include a traditional pressure ring, a speed ring and a current ring PI control loop, the control instructions of the speed ring and the current ring can quickly change with the set input oil pressure instructions, and the response time of the speed ring and the current ring is much faster than that of the oil pressure ring, so the speed ring and the current ring can be equivalent to 1, and the instantaneous displacement q of the hydraulic pumpt Oil pressure P of the hydraulic pipeline fdb The closed pipeline transfer function between can be equivalent to the inertia link, so we can get the following Figure 4 The transfer function block diagram of the hydraulic transmission mechanism is shown in the figure, where K pl is the leakage coefficient of the hydraulic pipeline, v p is the theoretical hydraulic oil volume in the hydraulic pipeline, β e is the elastic modulus of the hydraulic oil. The theoretical hydraulic oil volume and hydraulic oil elastic modulus can be determined according to actual use requirements.

[0074] Since the real-time pipeline oil pressure is related to the real-time instantaneous displacement, the real-time hydraulic oil volume of the hydraulic pipeline, the leakage coefficient of the hydraulic pipeline and the elastic modulus of the hydraulic oil, in the case of uneven gear pump meshing, different input oil pressure P set Under control, the leakage coefficient K of the hydraulic pipeline pl Rapid changes, resulting in the instantaneous displacement q of the hydraulic pump t Oil pressure P of the hydraulic pipeline fdb The transfer function between them changes, making the hydraulic pipeline oil pressure P fdb Fluctuation. Therefore, the leakage coefficient can be determined based on the real-time instantaneous displacement of the hydraulic pump and the real-time pipeline oil pressure of the hydraulic pipeline, combined with the theoretical hydraulic oil volume and elastic modulus of the hydraulic pipeline. After determining the oil leakage amount of the hydraulic pipeline, Figure 4 Based on the closed pipeline transfer function, the oil leakage is introduced, such as Figure 5 As shown, the actual oil volume input to the hydraulic pipeline is obtained as the real-time instantaneous displacement minus the oil leakage volume, and the pipeline oil pressure of the hydraulic pipeline is controlled to adjust the pipeline oil pressure according to the oil leakage volume.

[0075] Among them, the real-time input oil pressure can be determined according to actual use requirements; during the pressure maintaining stage, the real-time input oil pressure usually remains unchanged. The real-time pipeline oil pressure can be the pipeline oil pressure at the current moment, and the historical pipeline oil pressure can be the pipeline oil pressure at the previous moment. The historical pipeline oil pressure of the hydraulic pipeline is used as feedback, combined with the real-time input oil pressure at the current moment through the pressure loop, speed loop, and current loop, and the instantaneous displacement at the current moment can be determined. Specifically, the historical pipeline oil pressure of the hydraulic pipeline is used as feedback, combined with the real-time input oil pressure at the current moment through the pressure loop, speed loop, and current loop to adjust the speed of the motor in the hydraulic transmission mechanism, and then according to the current speed of the motor and the displacement of the hydraulic pump, the real-time instantaneous displacement of the hydraulic pump can be determined, that is, the instantaneous displacement at the current moment is determined. The pipeline oil pressure can be obtained by detection of a pressure gauge set in the hydraulic pipeline.

[0076] In specific implementation, during the control process of the hydraulic transmission mechanism, the initial input oil pressure can be determined according to actual use requirements. After determining the initial instantaneous displacement of the hydraulic pump based on the initial input oil pressure, the initial pipeline oil pressure is obtained by combining the transfer function between the instantaneous displacement and the pipeline oil pressure and the initial instantaneous displacement. The initial pipeline oil pressure is converted to the motor speed, and the motor operation is controlled, thereby controlling the pipeline oil pressure of the hydraulic pipeline to reach the initial pipeline oil pressure, so that the hydraulic transmission mechanism starts to work. Thereafter, the real-time pipeline oil pressure is detected, and combined with the real-time instantaneous displacement, the real-time oil leakage is obtained. The real-time oil leakage is converted to the corresponding motor speed to obtain a speed adjustment value, which is superimposed on the set speed, thereby adjusting the real-time speed of the motor according to the oil leakage to adjust the real-time pipeline oil pressure. Among them, the set speed can be obtained by converting the real-time input oil pressure to the motor speed.

[0077] As an implementation method, step S200 may include:

[0078] Step S210: Obtain the relationship function between the oil leakage amount, the instantaneous displacement and the pipeline oil pressure.

[0079] Step S220: Determine the real-time oil leakage amount according to the relationship function, the real-time instantaneous displacement and the real-time pipeline oil pressure.

[0080] In this embodiment, Figure 5 As shown, on the basis of the closed-circuit transfer function between instantaneous displacement and pipeline oil pressure, the oil leakage amount can be added as an input to obtain a relationship function between the oil leakage amount and the instantaneous displacement and pipeline oil pressure. After obtaining the real-time instantaneous displacement and the real-time pipeline oil pressure, the real-time oil leakage amount can be obtained by combining the relationship function.

[0081] In this embodiment, step S210 may include:

[0082] Step S211: Obtain the transfer function between the input oil pressure and the pipeline oil pressure.

[0083] Step S212: Taking the oil leakage amount as input and the instantaneous displacement and pipeline oil pressure as output, the transfer function is transformed to obtain a relationship function.

[0084] In this embodiment, the relationship function can be obtained by analyzing the mathematical model of the hydraulic transmission mechanism, obtaining the transfer function between the input oil pressure and the pipeline oil pressure, taking the oil leakage amount as input and the instantaneous displacement and pipeline oil pressure as output, and transforming the transfer function.

[0085] When implementing it specifically, Figure 5 As shown in the figure, the instantaneous displacement of the hydraulic pump can be obtained by combining the input oil pressure and the historical pipeline oil pressure through the pressure loop, speed loop, and current loop, and the closed pipeline transfer function f(s) of the hydraulic pipeline is:

[0086] f(s)=f(K pl ,v e ,β e );

[0087] Therefore, based on the closed pipeline transfer function, pipeline oil pressure and instantaneous displacement, the transfer function between the input oil pressure and pipeline oil pressure can be obtained. Then, the oil leakage is used as input, the instantaneous displacement and pipeline oil pressure are used as output, and the transfer function is transformed to obtain the relationship function G(s):

[0088]

[0089] Among them, O loss The amount of oil leakage.

[0090] In this embodiment, step S211 may include: obtaining the oil pressure change curve of the hydraulic transmission mechanism under the input pressure function test; performing data fitting on the oil pressure change curve to obtain the oil pressure change function; and obtaining the transfer function based on the input pressure function and the oil pressure change function.

[0091] In this embodiment, the input pressure function can be set according to actual use requirements. Preferably, the input pressure function is a pressure step function that includes multiple input pressures. Data fitting is implemented by selecting a data fitting algorithm based on actual use requirements. The oil pressure variation curve can be a variation curve of the pipeline oil pressure in the hydraulic pipeline under different input pressures. Correspondingly, the oil pressure variation function can be a variation function of the pipeline oil pressure in the hydraulic pipeline under different input pressures. Therefore, after obtaining the input pressure function and oil pressure variation function of the hydraulic transmission mechanism, Laplace transforms are simultaneously performed on the input pressure function and the oil pressure variation function to obtain the transfer function between the input oil pressure and the pipeline oil pressure.

[0092] In a specific implementation, the hydraulic transmission mechanism can be tested with multiple input pressure step settings based on the pressure step function to obtain the oil pressure change curve of the hydraulic oil pipe, and the oil pressure change curve can be data fitted to obtain the oil pressure change function; the transfer function can be obtained based on the input pressure function and the oil pressure change function.

[0093] Specifically, the step of "performing data fitting on the oil pressure variation curve to obtain the oil pressure variation function" may include: discretizing the oil pressure variation curve to obtain a plurality of discrete pressure data; and performing data fitting on the plurality of discrete pressure data to obtain the oil pressure variation function.

[0094] In this embodiment, the data fitting process of the oil pressure variation curve can be implemented using MATLAB (mathematical modeling and simulation software). After obtaining the oil pressure variation curve, the oil pressure variation curve can be discretized and then imported into MATLAB for data fitting to obtain the oil pressure variation function. The data discretization algorithm can be selected according to actual use requirements.

[0095] As an implementation manner, after step S210, the method may further include: discretizing the relationship function to obtain a discretized control equation.

[0096] Step S220 may include determining the real-time oil leakage amount according to the control equation, the real-time instantaneous displacement and the real-time pipeline oil pressure.

[0097] In this embodiment, the relationship function is discretized to obtain a control equation that can be implemented in a digital controller. The control equation can be a difference equation. The discretization process can be implemented by selecting a discretization algorithm based on actual usage requirements.

[0098] It should be noted that, by comparing the hydraulic transmission mechanism control method of this embodiment with the traditional PI control method, field measured data show that the hydraulic transmission mechanism control method of this embodiment can reduce oil pressure fluctuations by at least 50%, effectively improving the process accuracy of the hydraulic transmission mechanism.

[0099] Therefore, this embodiment provides a hydraulic transmission mechanism control method, which constructs a transfer function of the hydraulic transmission mechanism, converts the relationship function between the oil leakage amount and the pipeline oil pressure and the instantaneous displacement, determines the real-time oil leakage amount of the hydraulic pipeline according to the real-time instantaneous displacement of the hydraulic pump, the real-time pipeline oil pressure of the hydraulic pipeline and the relationship function, and adjusts the speed of the motor to adjust the real-time pipeline oil pressure, thereby directly adjusting the real-time pipeline oil pressure according to the oil leakage amount of the hydraulic pipeline to avoid excessive fluctuations in the pipeline oil pressure. When adjusting the pipeline oil pressure, the adjustment amount of the pipeline oil pressure is not affected by the gain parameters of the PI control loop before the hydraulic pump in the hydraulic transmission mechanism, and the control accuracy is relatively high.

[0100] In addition, an embodiment of the present application further proposes a computer storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the steps of the hydraulic transmission mechanism control method as described above are implemented. Therefore, no further description will be given here. In addition, the description of the beneficial effects of adopting the same method will not be repeated. For technical details not disclosed in the computer-readable storage medium embodiment involved in this application, please refer to the description of the method embodiment of this application. As an example, program instructions can be deployed to be executed on one computing device, or on multiple computing devices located at one location, or on multiple computing devices distributed at multiple locations and interconnected by a communication network.

[0101] The preferred embodiments of the present application have been described above with the illustrated embodiments, and are not intended to limit the scope of patent protection for the present application, and any equivalent structures or equivalent processes transformed by the contents of the specification and drawings of the present application, or directly or indirectly applied to other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for controlling a hydraulic transmission mechanism, characterized in that: The method comprises: obtaining a real-time instantaneous displacement of a hydraulic pump in a hydraulic transmission mechanism and a real-time line oil pressure of a hydraulic pipeline; the real-time instantaneous displacement is determined based on the real-time input oil pressure of the hydraulic transmission mechanism and the historical line oil pressure of the hydraulic pipeline, specifically, using the historical line oil pressure as feedback and the real-time input oil pressure as input, obtaining a current speed of a motor in the hydraulic transmission mechanism through a control loop of the hydraulic transmission mechanism, and obtaining the real-time instantaneous displacement based on the current speed and the displacement of the hydraulic pump; Determining the real-time oil leakage of the hydraulic pipeline according to the real-time instantaneous displacement and the real-time pipeline oil pressure; determining a speed adjustment value of the motor according to the real-time oil leakage amount; According to the speed adjustment value, the real-time speed of the motor is adjusted to regulate the real-time pipeline oil pressure.

2. The method according to claim 1, wherein The step of determining the real-time oil leakage amount of the hydraulic pipeline based on the real-time instantaneous displacement and the real-time pipeline oil pressure includes: Obtain the relationship function between oil leakage, instantaneous displacement and pipeline oil pressure; The real-time oil leakage amount is determined according to the relationship function, the real-time instantaneous displacement and the real-time pipeline oil pressure.

3. The method according to claim 2, wherein After the step of obtaining the relationship function between the oil leakage amount, the instantaneous displacement and the pipeline oil pressure, the method further includes: Discretizing the relationship function to obtain a discretized control equation; The step of determining the real-time oil leakage amount based on the relationship function, the real-time instantaneous displacement and the real-time pipeline oil pressure includes: The real-time oil leakage amount is determined according to the control equation, the real-time instantaneous displacement and the real-time pipeline oil pressure.

4. The method according to claim 2, wherein The step of obtaining the relationship function between the oil leakage amount, the instantaneous displacement and the pipeline oil pressure includes: obtaining a transfer function between the input oil pressure and the pipeline oil pressure; The oil leakage amount is used as input, the instantaneous displacement and the pipeline oil pressure are used as output, and the transfer function is transformed to obtain the relationship function.

5. The method according to claim 4, wherein The step of obtaining a transfer function between the input oil pressure and the pipeline oil pressure includes: Obtaining an oil pressure variation curve of the hydraulic transmission mechanism under an input pressure function test; Performing data fitting on the oil pressure variation curve to obtain an oil pressure variation function; The transfer function is obtained according to the input pressure function and the oil pressure change function.

6. The method according to claim 5, wherein The step of performing data fitting on the oil pressure variation curve to obtain the oil pressure variation function includes: Discretizing the oil pressure variation curve to obtain a plurality of discrete pressure data; Data fitting is performed on the plurality of discrete pressure data to obtain the oil pressure variation function.

7. The method according to claim 5, wherein The input pressure function is a pressure step function including a plurality of input pressures.

8. A hydraulic transmission mechanism control device, characterized in that: The device includes: a memory, a processor, and a hydraulic transmission mechanism control program stored in the memory and executable on the processor. The hydraulic transmission mechanism control program is configured to implement the steps of the hydraulic transmission mechanism control method according to any one of claims 1 to 7.

9. A hydraulic transmission mechanism control system, characterized in that: The system comprises: A hydraulic transmission mechanism, comprising a connected motor, a hydraulic pump, and hydraulic pipelines; The hydraulic transmission mechanism control device according to claim 8; The hydraulic transmission mechanism control device is connected to the motor.

10. A computer-readable storage medium, characterized in that The storage medium stores a computer program, which, when executed by a processor, implements the steps of the hydraulic transmission mechanism control method according to any one of claims 1 to 7.

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