CN118756779A - Control method of working machine, working machine, control device and storage medium - Google Patents

Abstract

The present application discloses a control method for a working machine, a working machine, a control device and a storage medium, wherein the working machine includes a hydraulic pump, a hydraulic motor and an engine. The control method includes: obtaining the current speed gear of the engine; adjusting the flow of the hydraulic pump according to the current speed gear to perform constant flow control on the hydraulic pump; obtaining the given displacement of the hydraulic motor when the hydraulic pump is under constant flow control; determining the motor current value corresponding to the hydraulic motor according to the preset displacement and the given displacement, wherein the preset displacement is determined based on the current speed gear; and adjusting the current corresponding to the hydraulic motor according to the motor current value to control the working machine. The present application can improve the starting speed of the working machine.

Description

Control method of working machine, working machine, control device and storage medium

Technical Field

The present application relates to the technical field of working machinery, and specifically to a control method for a working machinery, a working machinery, a control device, and a storage medium.

Background Art

When operating machinery (such as excavators) is started in high mountains, the air density, temperature, hydraulic viscosity, and the set horsepower conditions will cause initial starting difficulties. Due to these environmental influences, the engine can burn less oxygen per unit time under the same torque load than on flat ground, resulting in a decrease in the engine's output speed per minute, which causes the operating machinery to start slowly in special environments.

Summary of the invention

The purpose of the embodiments of the present application is to provide a control method for an operating machine, an operating machine, a control device and a storage medium, so as to solve the problem of slow starting speed of the operating machine in the prior art.

In order to achieve the above-mentioned object, the first aspect of the present application provides a control method for an operating machine, the operating machine comprising a hydraulic pump, a hydraulic motor, and an engine, the control method comprising:

Get the current speed gear of the engine;

According to the current speed gear, the flow of the hydraulic pump is adjusted to control the hydraulic pump at a constant flow rate;

Under the condition of constant flow control of the hydraulic pump, obtaining a given displacement of the hydraulic motor;

Determining a motor current value corresponding to the hydraulic motor according to a preset displacement and a given displacement, wherein the preset displacement is determined based on the current speed gear; and

The current corresponding to the hydraulic motor is adjusted according to the motor current value to control the operating machine.

In the embodiment of the present application, adjusting the flow rate of the hydraulic pump according to the current speed gear includes:

According to the current speed gear, determine a first current value and a second current value corresponding to the hydraulic pump, the first current value is associated with the torque of the engine, and the second current value is associated with the actual load rate of the engine;

The smaller current value between the first current value and the second current value is determined as the main pump current value corresponding to the hydraulic pump;

Adjust the flow of the hydraulic pump according to the main pump current value.

In the embodiment of the present application, determining the first current value corresponding to the hydraulic pump according to the current speed gear includes:

Determine the engine speed corresponding to the current speed gear;

determining an engine torque corresponding to an engine speed;

A current value corresponding to the engine torque is determined as a first current value.

In the embodiment of the present application, determining the second current value corresponding to the hydraulic pump according to the current speed gear includes:

The power of the engine corresponding to the current speed gear is calculated through the preset PID control algorithm to obtain the actual load rate of the engine;

The current value corresponding to the actual load factor is determined as the second current value.

In the embodiment of the present application, determining the motor current value corresponding to the hydraulic motor according to the preset displacement and the given displacement includes:

The smaller displacement between the preset displacement and the given displacement is determined as the target displacement corresponding to the hydraulic motor;

The current value corresponding to the target displacement is determined as the motor current value corresponding to the hydraulic motor.

In the embodiment of the present application, the preset displacement is obtained by the following steps:

Acquire a first average vehicle speed of the working machine in a first operating state, and a second average vehicle speed of the working machine in a second operating state;

Determining a first displacement corresponding to the hydraulic motor according to the first average vehicle speed, and determining a second displacement corresponding to the hydraulic motor according to the second average vehicle speed;

Determine the smaller displacement of the first displacement and the second displacement as the preset displacement;

Among them, the first operating state represents that the working machine operates in the first speed range in the current speed gear, and the second operating state represents that the working machine operates in the second speed range in the current speed gear. The minimum speed included in the first speed range is greater than the maximum speed included in the second speed range.

In the embodiment of the present application, obtaining a given displacement of the hydraulic motor includes:

Obtaining an initial position and a target position corresponding to a pedal of the operating machine;

Determine the pedal stroke corresponding to the pedal according to the initial position and the target position;

The given displacement is determined based on the pedal travel.

A second aspect of the present application provides a control device for an operating machine, wherein the operating machine includes a hydraulic pump, a hydraulic motor and an engine, and the control device includes:

a first solenoid valve configured to adjust the displacement of the hydraulic motor;

a second solenoid valve configured to adjust a flow rate of the hydraulic pump;

The controller is configured to implement the control method of the above-mentioned working machine.

A third aspect of the present application provides a working machine, comprising:

engine;

Hydraulic pumps;

Hydraulic motors; and

A control device for the above-mentioned working machine.

A fourth aspect of the present application provides a machine-readable storage medium having instructions stored thereon, the instructions being used to enable a machine to execute the above-mentioned control method for a working machine.

Through the above technical solution, the hydraulic pump is first controlled to have a constant flow rate. When the hydraulic pump maintains a constant flow rate output, the smaller value between the given displacement and the preset displacement of the hydraulic motor is determined as the target displacement; the second target current value of the hydraulic motor is further determined according to the target displacement. Using the second target current value as a reference, the current corresponding to the hydraulic motor can be adjusted so that it can stably work near the second target current value, thereby maintaining the displacement of the hydraulic motor at the target displacement, which can be the smallest displacement that is acceptable while ensuring the normal operation of the operating machinery. When the output flow rate of the hydraulic pump is constant, the smaller the displacement of the hydraulic motor, the higher the speed, thereby increasing the starting speed of the operating machinery.

Other features and advantages of the embodiments of the present application will be described in detail in the subsequent specific implementation section.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present application, but do not constitute a limitation on the embodiments of the present application. In the accompanying drawings:

FIG1 schematically shows a flow chart of a control method for a working machine according to an embodiment of the present application;

FIG2 schematically shows a structural block diagram of a control device for a working machine according to an embodiment of the present application;

3a and 3b schematically show a graph showing a relationship between a hydraulic pump current and a travel motor speed according to an embodiment of the present application.

DETAILED DESCRIPTION

In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. It should be understood that the specific implementation methods described herein are only used to illustrate and explain the embodiments of the present application, and are not used to limit the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

In the embodiments of the present application, the hydraulic motor, the hydraulic travel motor and the travel motor can be used interchangeably.

Fig. 1 schematically shows a flow chart of a control method for a working machine according to an embodiment of the present application. As shown in Fig. 1, an embodiment of the present application provides a control method for a working machine, the working machine may include a hydraulic pump, a hydraulic motor and an engine, and the method may include the following steps.

Step 101: Obtain the current speed gear of the engine.

Specifically, in the embodiment of the present application, the engine may be provided with a plurality of speed gears, and each speed gear may correspond to a preset engine speed. For example, when the driver sets the engine to the current gear by operating the shift mechanism, the gear information may be read to obtain the current speed gear. In the embodiment of the present application, an example of a working machine may be an excavator. The walking system of the excavator may be a hydraulic closed walking system or a walking walking system.

Step 102: According to the current speed gear, the flow of the hydraulic pump is adjusted to perform constant flow control on the hydraulic pump.

In one embodiment of the present application, a PID control algorithm, for example, can be used to perform constant flow control on the hydraulic pump. For example, a flow set value can be determined according to actual needs, and the flow set value can be input into the PID control algorithm (controller), and the current of the hydraulic pump can be adjusted according to the flow set value to adjust the output flow of the hydraulic pump. In one example, the current of the hydraulic pump may include the input current of the hydraulic pump. In this case, the magnitude of the input current of the hydraulic pump can be adjusted to adjust the output flow of the hydraulic pump. In another example, the output flow of the hydraulic pump can be adjusted by adjusting the opening of the solenoid valve (such as an electromagnetic proportional valve) of the hydraulic pump. In this example, the current of the hydraulic pump can include the input current of the solenoid valve, and the opening of the solenoid valve can be adjusted by adjusting the input current of the solenoid valve, thereby adjusting the output flow of the hydraulic pump.

In a preferred embodiment of the present application, adjusting the flow rate of the hydraulic pump according to the current speed gear may include:

According to the current speed gear, determine the first current value and the second current value corresponding to the hydraulic pump; the first current value is associated with the torque of the engine, and the second current value is associated with the actual load rate of the engine;

The smaller current value between the first current value and the second current value is determined as the main pump current value corresponding to the hydraulic pump;

Adjust the flow of the hydraulic pump according to the main pump current value.

In the embodiment of the present application, determining the first current value corresponding to the hydraulic pump according to the current speed gear includes:

Determine the engine speed corresponding to the current speed gear;

determining an engine torque corresponding to an engine speed;

A current value corresponding to the engine torque is determined as a first current value.

Specifically, the correspondence or function expression between the speed gear and the engine speed can be pre-set. After obtaining the current speed gear, the engine speed corresponding to the current speed gear can be obtained according to the correspondence or function expression. The relationship or function expression between the engine speed and the engine torque can also be pre-set. The engine torque corresponding to the engine speed can be obtained according to the relationship or function expression. The correspondence or function expression between the engine torque and the hydraulic pump current can also be pre-set. The first current value of the hydraulic pump corresponding to the engine torque can be obtained according to the correspondence or function expression.

In the embodiment of the present application, determining the second current value corresponding to the hydraulic pump according to the current speed gear includes:

The power of the engine corresponding to the current speed gear is calculated through the preset PID control algorithm to obtain the actual load rate of the engine;

The current value corresponding to the actual load factor is determined as the second current value.

Specifically, since the engine power is certain, the engine power is equal to the engine speed multiplied by the engine torque. Each speed gear corresponds to an engine power, and the power of the hydraulic pump can be matched by the engine power. The actual load rate of the hydraulic pump can be obtained by inputting the power of the hydraulic pump into the preset PID control algorithm. The corresponding relationship or function expression between the actual load rate of the hydraulic pump and the second current value of the hydraulic pump can be predetermined. After the actual load rate of the hydraulic pump is determined by the above technical solution, the second current value corresponding to the current actual load rate can be obtained according to the corresponding relationship or function expression. After determining the second current value, the smaller of the first current value and the second current value can be determined as the main pump current value corresponding to the hydraulic pump. The flow rate of the hydraulic pump (i.e., the output flow rate of the hydraulic pump) is adjusted according to the main pump current value corresponding to the hydraulic pump, thereby realizing constant flow control of the output flow rate of the hydraulic pump.

The main pump current value is determined in the above manner, thereby determining the target flow corresponding to the main pump current value, and performing constant flow control on the hydraulic pump to stabilize the output flow of the hydraulic pump at the target flow. In this way, the hydraulic pump can be in normal operation with a stable output flow, which can be more conducive to adjusting the displacement of the hydraulic motor to increase the starting speed of the operating machinery.

Step 103: Under the condition of constant flow control of the hydraulic pump, obtain the given displacement of the hydraulic motor.

In an embodiment of the present application, obtaining a given displacement of a hydraulic motor includes: obtaining an initial position and a corresponding target position corresponding to a pedal of the working machine; determining a pedal stroke corresponding to the pedal based on the initial position and the target position; and determining a given displacement based on the pedal stroke.

When the driver steps on the accelerator pedal of the working machine, the position of the accelerator pedal after being stepped on (or the position change relative to the initial position (or accelerator pedal stroke)) can correspond to the set displacement (given displacement) of the hydraulic motor. By reading the position or stroke of the accelerator pedal, the given displacement of the hydraulic motor can be obtained. Those skilled in the art can understand that although the accelerator pedal is used as an example, it is also applicable to other forms of accelerators or acceleration devices.

Step 104: determining a motor current value corresponding to the hydraulic motor according to a preset displacement and a given displacement, wherein the preset displacement is determined based on the current speed gear; and

Step 105: Adjust the current corresponding to the hydraulic motor according to the motor current value to control the working machine.

In the embodiment of the present application, the preset displacement can be a fixed quantity, and the given displacement can be a variable. Each speed gear can correspond to a preset displacement, and the corresponding preset displacement can be determined according to the current speed gear. When the hydraulic pump outputs a constant flow to the hydraulic motor and the given displacement is lower than the preset displacement, it can be known that the speed corresponding to the given displacement will be higher than the speed corresponding to the preset displacement according to the flow equal to the product of the speed and the displacement. Similarly, when the given displacement is higher than the preset displacement, the speed corresponding to the given displacement will be lower than the speed corresponding to the preset displacement. The corresponding relationship or function expression between the displacement and the current can be pre-set, and the smaller of the given displacement and the preset displacement is determined as the target displacement, and the target current value corresponding to the target displacement can be determined according to the target displacement. It should be noted that the target current value is the current value input to the hydraulic motor under ideal conditions. By controlling the current actual current value of the hydraulic motor to be as close to the target current value as possible (or stable at the target current value), it can be ensured that the speed corresponding to the actual displacement of the hydraulic motor is the highest speed that the hydraulic motor can reach when the current constant flow is input to the hydraulic motor, thereby realizing the accelerated start of the operating machinery.

Through the above technical solution, the output flow of the hydraulic pump is adjusted according to the current speed gear of the engine, thereby realizing constant flow control of the output flow of the hydraulic pump. Under the condition that the constant flow control of the hydraulic pump is satisfied, the given displacement of the hydraulic motor is obtained, and the smaller of the given displacement and the preset displacement is determined as the target displacement. The target current value corresponding to the target displacement is used as the ideal current value input to the hydraulic motor. In the case where the flow rate transmitted to the hydraulic motor by the hydraulic pump is a constant flow rate, according to the relationship that the flow rate is equal to the product of the speed and the displacement, that is, the speed and the displacement are inversely proportional, the actual displacement of the hydraulic motor is adjusted by adjusting the actual current of the hydraulic motor to be as close to the target current value as possible (or stabilized at the target current value), so as to adjust the speed of the hydraulic motor to the highest speed that the hydraulic motor can reach under the above conditions, thereby improving the starting speed of the operating machinery.

In an embodiment of the present application, determining the motor current value corresponding to the hydraulic motor based on the preset displacement and the given displacement includes: determining the smaller displacement between the preset displacement and the given displacement as the target displacement corresponding to the hydraulic motor; and determining the current value corresponding to the target displacement as the motor current value corresponding to the hydraulic motor.

In an embodiment of the present application, the preset displacement can be obtained by the following steps: obtaining a first average vehicle speed when the working machine is in a first operating state, and a second average vehicle speed when the working machine is in a second operating state; determining a first displacement corresponding to the hydraulic motor according to the first average vehicle speed, and determining a second displacement corresponding to the hydraulic motor according to the second average vehicle speed; determining the smaller displacement between the first displacement and the second displacement as the preset displacement; wherein the first operating state represents that the working machine is operating in a first speed range in the current speed gear, and the second operating state represents that the working machine is operating in a second speed range in the current speed gear, and the minimum speed included in the first speed range is greater than the maximum speed included in the second speed range.

In the embodiment of the present application, the first operating state may be a high-speed walking state of the operating machine, and the second operating state may be a low-speed walking state of the operating machine. Each speed gear of the operating machine corresponds to a high-speed walking state and a low-speed walking state. During the walking process of the operating machine, the speed state can be switched by selecting a corresponding walking state button or a lever. The high-speed walking state and the low-speed walking state refer to the operating machine walking within a specific speed range, and the state of the operating machine at this time is the high-speed walking state or the low-speed walking state. If the operating machine is not walking in the high-speed walking state or the low-speed walking state, the operating machine is walking in a normal state. Preferably, the speed range of the high-speed walking state may be [15.2-15.9] km/h, and the speed range of the low-speed walking state may be [7.2-7.9] km/h. After respectively determining the average speeds in the high-speed walking state and the low-speed walking state, the displacement corresponding to the current speed average value may be determined by the predetermined relationship or function expression between the speed and the displacement.

Through the above technical solution, the output flow of the hydraulic pump is adjusted according to the current speed gear of the engine, thereby realizing constant flow control of the output flow of the hydraulic pump. When the hydraulic pump maintains a constant flow output, the smaller of the given displacement of the hydraulic motor and the preset optimal displacement is determined as the target displacement. The target current value corresponding to the target displacement is used as the ideal current value input to the hydraulic motor, so as to control the actual current value input to the hydraulic motor to maintain at the target current value. For example, the given displacement corresponding to when the accelerator pedal is operated is compared with the preset displacement determined by the above method, and the smaller one is taken as the target displacement, so as to determine the maximum speed that the hydraulic motor can reach, so as to improve the starting speed of the working machinery.

FIG2 schematically shows a block diagram of a control device for a working machine according to an embodiment of the present application. As shown in FIG2 , an embodiment of the present application provides a control device, which can be applied to a working machine, which can include a hydraulic pump, a hydraulic motor and an engine, and the control device can include:

A first solenoid valve 220 configured to adjust the displacement of the hydraulic motor;

A second solenoid valve 230 , configured to adjust the flow rate of the hydraulic pump;

The controller 210 is configured to implement the above-mentioned control method for the working machine.

In the embodiment of the present application, an example of the first solenoid valve 220 may include an electromagnetic proportional valve.

In an embodiment of the present application, the controller 210 may be configured to control the output flow of the hydraulic pump. In one example, the controller 210 may adjust the speed of the hydraulic pump by adjusting the current of the hydraulic pump, thereby controlling the output flow of the hydraulic pump. In another example, the controller 210 may adjust the opening of the solenoid valve by adjusting the current of a flow regulating element (e.g., a solenoid valve) provided in the hydraulic pump, thereby controlling the output flow of the hydraulic pump. In this example, the control device may further include a second solenoid valve 230, configured to adjust the flow of the hydraulic pump. Examples of the second solenoid valve 230 may include an electromagnetic proportional valve.

Specifically, in the embodiment of the present application, the controller 210 may be configured as follows:

Get the current speed gear of the engine;

According to the current speed gear, the flow of the hydraulic pump is adjusted to control the hydraulic pump at a constant flow rate;

Under the condition of constant flow control of the hydraulic pump, obtaining a given displacement of the hydraulic motor;

Determining a motor current value corresponding to the hydraulic motor according to a preset displacement and a given displacement, wherein the preset displacement is determined based on the current speed gear; and

The current corresponding to the hydraulic motor is adjusted according to the motor current value to control the operating machine.

An embodiment of the present application also provides a working machine, which may include the above-mentioned engine, hydraulic pump and hydraulic motor, and a control device for the working machine of the above-mentioned embodiment.

FIG3a and FIG3b schematically show a diagram showing a change relationship between the hydraulic pump current and the travel motor speed according to an embodiment of the present application. As shown in FIG3a and FIG3b, in the embodiment of the present application, the ordinate on the left side of FIG3a and FIG3b represents the flow rate of the hydraulic pump, the abscissa represents the pressure of the hydraulic pump, and the ordinate on the right side represents the torque of the travel motor. Assuming that the load rate of the hydraulic pump required by the operating machine at this time is A, the control current of the hydraulic pump at this time can be calculated through the preset relationship of the PID algorithm when the load rate is A. The control current can be represented by I ₂ , and the target current value of the hydraulic pump is represented by I ₁ or I _3. If the target current value is less than the control current I ₂ , that is, I ₁ <I ₂ , the corresponding pressure P ₁ >P ₂ at this time, then the constant power values corresponding to I ₁ and I ₂ are W _h1 >W _h2 . When the travel motor is in the case of constant torque, the higher the power, the higher the corresponding speed. If the target current value is greater than the control current I ₂ , that is, I ₃ >I ₂ , the corresponding pressure P ₂ >P ₃ at this time. When the flow rate is constant, the power corresponding to the target current value (i.e., W _h3 ) is less than the load rate A of the hydraulic pump at this time (i.e., W _h2 ), that is, when the travel motor is at constant torque, the speed corresponding to the power W _h2 and W _h3 is V ₂ >V ₃ . At this time, it is necessary to reduce the load rate A of the hydraulic pump so that I ₂ ≥I ₃ , then the corresponding travel motor speed V ₃ is greater than or equal to V ₂ , and under this target current, the corresponding speed also increases.

In FIG3a, when the displacement of the travel motor remains unchanged, the higher the speed of the travel motor, the higher the corresponding flow rate, which is consistent with the fact that the flow rate is equal to the product of the speed and the displacement, that is, the speed and the displacement are inversely proportional. The flow rate corresponding to speed 1 is q _h1 , the flow rate corresponding to speed 2 is q _h2 , and the flow rate corresponding to speed 3 is q _h3 . Speed 1, speed 2 and speed 3 also correspond to power W _h1 , W _h2 and W _h3 respectively. Since the product of speed and torque is equal to power, the curve representing speed can also represent power. When the power is constant, the greater the pressure, the smaller the flow rate, and the lower the corresponding speed of the travel motor; the smaller the pressure, the greater the flow rate, and the higher the corresponding speed of the travel motor. In FIG3b, currents I ₁ , I ₂ and I ₃ represent the currents of three hydraulic pumps of different sizes, respectively. The smaller the current, the greater the corresponding hydraulic pump pressure.

An embodiment of the present application also provides a machine-readable storage medium, on which instructions are stored, and the instructions are used to enable a machine to execute the above-mentioned control method for the working machine.

Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

The present application is described with reference to the flowchart and/or block diagram of the method, device (system), and computer program product according to the embodiment of the present application. It should be understood that each process and/or box in the flowchart and/or block diagram, as well as the combination of the process and/or box in the flowchart and/or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for implementing the functions specified in one process or multiple processes in the flowchart and/or one box or multiple boxes in the block diagram.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured product including an instruction device that implements the functions specified in one or more processes in the flowchart and/or one or more boxes in the block diagram.

These computer program instructions may also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, whereby the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more processes in the flowchart and/or one or more boxes in the block diagram.

In a typical configuration, a computing device includes one or more processors (CPU), input/output interfaces, network interfaces, and memory.

The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and/or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims (10)

1. A control method of a working machine including a hydraulic pump, a hydraulic motor, and an engine, characterized by comprising:

acquiring the current speed gear of the engine;

according to the current speed gear, the flow of the hydraulic pump is regulated so as to control the constant flow of the hydraulic pump;

Under the condition of constant flow control of the hydraulic pump, obtaining a given displacement of the hydraulic motor;

Determining a motor current value corresponding to the hydraulic motor according to a preset displacement and the given displacement, wherein the preset displacement is determined based on the current speed gear; and

And adjusting the current corresponding to the hydraulic motor according to the motor current value so as to control the working machine.

2. The control method according to claim 1, characterized in that said adjusting the flow rate of the hydraulic pump according to the current speed level comprises:

determining a first current value and a second current value corresponding to the hydraulic pump according to the current speed gear; the first current value is associated with a torque of the engine, and the second current value is associated with an actual load factor of the engine;

determining the smaller current value of the first current value and the second current value as a main pump current value corresponding to the hydraulic pump;

And adjusting the flow of the hydraulic pump according to the main pump current value.

3. The control method according to claim 2, wherein determining a first current value corresponding to the hydraulic pump according to the current speed level includes:

determining an engine speed corresponding to the current speed gear;

determining an engine torque corresponding to the engine speed;

and determining a current value corresponding to the engine torque as the first current value.

4. The control method according to claim 2, wherein determining a second current value corresponding to the hydraulic pump according to the current speed level includes:

calculating the power of the engine corresponding to the current speed gear through a preset PID control algorithm to obtain the actual load rate corresponding to the engine;

and determining a current value corresponding to the actual load factor as the second current value.

5. The method of claim 1, wherein determining the motor current value for the hydraulic motor based on the preset displacement and the given displacement comprises:

determining the smaller displacement of the preset displacement and the given displacement as a target displacement corresponding to the hydraulic motor;

and determining a current value corresponding to the target displacement as a motor current value corresponding to the hydraulic motor.

6. The control method according to claim 1, characterized in that the preset displacement is obtained by:

acquiring a first average vehicle speed of the working machine in a first running state and a second average vehicle speed of the working machine in a second running state;

determining a first displacement corresponding to the hydraulic motor according to the first average vehicle speed, and determining a second displacement corresponding to the hydraulic motor according to the second average vehicle speed;

determining the smaller displacement of the first displacement and the second displacement as the preset displacement;

The first running state represents that the working machine runs in a first speed interval in the current speed gear, the second running state represents that the working machine runs in a second speed interval in the current speed gear, and the minimum speed included in the first speed interval is larger than the maximum speed included in the second speed interval.

7. The control method of claim 1, wherein the obtaining a given displacement of the hydraulic motor comprises:

Acquiring an initial position and a target position corresponding to a pedal of the working machine;

determining a pedal stroke corresponding to the pedal according to the initial position and the target position;

The given displacement is determined from the pedal travel.

8. A control device for a working machine, the working machine including a hydraulic pump, a hydraulic motor, and an engine, the control device comprising:

A first solenoid valve configured to adjust a displacement of the hydraulic motor;

A second solenoid valve configured to regulate a flow rate of the hydraulic pump;

A controller configured to execute the control method of the work machine according to any one of claims 1 to 7.

9. A work machine, comprising:

An engine;

A hydraulic pump;

A hydraulic motor; and

The control device for a work machine according to claim 8.

10. A machine-readable storage medium having stored thereon instructions for causing a machine to perform the method of controlling a work machine according to any one of claims 1 to 7.