Method and device for controlling working vehicle and engineering vehicle

Abstract

The embodiment of the present invention provides a method, device and engineering vehicle for controlling a working vehicle, which relates to the field of vehicles. The method includes: obtaining the rated power of the hydraulic system, the safe power of the hydraulic system and the engine response curve of the working vehicle; determining the allowable power of the engine according to the response time and the engine response curve; determining the power feedforward correction value according to the actual power of the hydraulic system and the allowable power of the engine; obtaining the engine speed drop ratio and the target speed drop ratio, and determining the power correction value according to the engine speed drop ratio and the target speed drop ratio; determining the maximum power of the hydraulic system according to the rated power of the hydraulic system, the power feedforward correction value and the power correction value; determining the maximum actual power of the hydraulic system of the working vehicle according to the maximum power of the hydraulic system and the safe power of the hydraulic system. The method realizes precise adjustment of the engine and effectively prevents over-adjustment of the system.

Description

Technical Field

[0001] The present invention relates to the field of vehicles, and in particular to a method and device for controlling an operating vehicle and an engineering vehicle. Background Art

[0002] In order to prevent the engine power of fuel vehicles and / or new energy vehicles from being higher than the power of the hydraulic system, the manufacturing and use costs are usually controlled. However, since cranes often work under low speed and heavy load conditions, if the power required by the hydraulic system exceeds the maximum power that the engine can currently output, the engine speed will be forced to decrease, which will cause the engine to run at a low efficiency, and in severe cases, may even cause the engine to stall.

[0003] In order to solve the above problems, the prior art uses the engine speed drop percentage to adaptively adjust the system power demand in real time. Specifically, when the engine speed drop ratio exceeds a certain set threshold, the system will automatically reduce the power demand of the hydraulic system; when the engine speed drop ratio is less than the set threshold, the power demand will automatically recover. This method only reduces the power demand of the hydraulic system after detecting that the engine starts to drop, without considering the feedforward control factor. The rate of change of the system load is closely related to the operator's operation mode. When the operator operates in a step-by-step manner (such as the handle opening suddenly increases to the maximum), the load rate will rise rapidly, and the system speed drop rate will be very fast. In this case, the control strategy of this scheme will be difficult to respond, so the control quality is not high. In addition, this scheme adjusts the power based on the engine speed drop ratio itself, which is easy to cause over-regulation, causing unstable engine speed or low efficiency.

[0004] The prior art also proposes a speed reduction control method based on load mutation. When the system load rate changes at a high rate, the required power of the hydraulic system is appropriately reduced; when the rate of change decreases, the required power of the hydraulic system is released. This method performs feedforward compensation adjustment based on the rate of change of the load rate, but does not consider the response factor of the engine, so the control quality and accuracy are poor.

[0005] In the power matching solution based on calibration learning, the vehicle calibrates the engine and oil pump parameters once every period of time or when the external environment changes (such as when the working environment changes to a plateau). This method is inefficient and inconvenient, and may cause unstable speed when the load rate suddenly increases, affecting the control experience. Summary of the invention

[0006] The purpose of the embodiments of the present invention is to provide a method and device for controlling a working vehicle and an engineering vehicle, wherein the method achieves precise adjustment of the engine and effectively prevents system over-adjustment.

[0007] In order to achieve the above object, an embodiment of the present invention provides a method for controlling a working vehicle, the method comprising:

[0008] Obtain the hydraulic system rated power, hydraulic system safety power and engine response curve of the working vehicle;

[0009] Determine the response initial power according to the engine speed of the working vehicle, obtain the response time when the actual power of the hydraulic system is greater than the response initial power, and determine the engine allowable power according to the response time and the engine response curve;

[0010] Determining a power feedforward correction value according to the actual power of the hydraulic system and the allowable power of the engine;

[0011] Obtaining an engine speed drop ratio and a target speed drop ratio, and determining a power correction value according to the engine speed drop ratio and the target speed drop ratio;

[0012] Determine the maximum power of the hydraulic system based on the rated power of the hydraulic system, the power feedforward correction value and the power correction value;

[0013] The maximum actual power of the hydraulic system of the working vehicle is determined according to the maximum power of the hydraulic system and the safety power of the hydraulic system.

[0014] Optionally, the engine response curve is a relationship curve between the power, rotation speed and response time of the engine of the working vehicle;

[0015] The safety power of the hydraulic system is determined according to the current minimum flow rate of the hydraulic system and the main oil pressure of the hydraulic system.

[0016] Optionally, determining the response initial power according to the engine speed of the working vehicle, obtaining the response time during which the actual power of the hydraulic system is greater than the response initial power, and determining the engine allowable power according to the response time and the engine response curve include:

[0017] Determining a speed gear according to the engine speed of the working vehicle, and obtaining a response initial power corresponding to the speed gear;

[0018] The time interval during which the actual power of the hydraulic system is greater than the initial response power is obtained as the response time;

[0019] Obtaining a unit change in the allowable power of the engine within a response time at the speed gear;

[0020] The engine allowable power is determined according to the obtained response initial power, response duration and unit change:

[0021] Engine allowable power = response initial power + unit change × response time.

[0022] Optionally, determining the power feedforward correction value according to the actual power of the hydraulic system and the allowed power of the engine includes:

[0023] The difference between the actual power of the hydraulic system and the allowed power of the engine is the power feedforward correction value.

[0024] Optionally, the acquiring the engine speed drop ratio and the target speed drop ratio, and determining the power correction value according to the engine speed drop ratio and the target speed drop ratio, comprises:

[0025] Obtain a change trend of the engine speed ratio, determine a target speed ratio trend of the engine according to the engine speed ratio and a target speed ratio, and when the target speed ratio trend does not meet the target requirement, adjust the power correction value until the target speed ratio trend meets the target requirement.

[0026] Optionally, determining the maximum power of the hydraulic system according to the rated power of the hydraulic system, the power feedforward correction value and the power correction value includes:

[0027] The maximum power of the hydraulic system is obtained by subtracting the power feedforward correction value and the power correction value in sequence from the rated power of the hydraulic system.

[0028] Optionally, determining the maximum actual power of the hydraulic system of the working vehicle according to the maximum power of the hydraulic system and the safety power of the hydraulic system includes:

[0029] The maximum value between the maximum power of the hydraulic system and the safety power of the hydraulic system is the maximum actual power of the hydraulic system of the working vehicle.

[0030] On the other hand, the present invention also provides a device for controlling a working vehicle, the device comprising:

[0031] An acquisition module, used for acquiring the hydraulic system rated power, hydraulic system safety power and engine response curve of the working vehicle;

[0032] A first processing module is used to determine a response initial power according to the engine speed of the working vehicle, obtain a response time when the actual power of the hydraulic system is greater than the response initial power, and determine an engine allowable power according to the response time and an engine response curve;

[0033] A second processing module, used for determining a power feedforward correction value according to the actual power of the hydraulic system and the allowed power of the engine;

[0034] A third processing module is used to obtain an engine speed drop ratio and a target speed drop ratio, and determine a power correction value according to the engine speed drop ratio and the target speed drop ratio;

[0035] A fourth processing module, used for determining the maximum power of the hydraulic system according to the rated power of the hydraulic system, the power feedforward correction value and the power correction value;

[0036] The fifth processing module is used to determine the maximum actual power of the hydraulic system of the working vehicle according to the maximum power of the hydraulic system and the safety power of the hydraulic system.

[0037] On the other hand, the present invention also proposes an engineering vehicle, which includes a device for controlling a working vehicle according to the above-mentioned method; the engineering vehicle is a fuel vehicle and / or a new energy vehicle; the new energy vehicle is a new energy working vehicle and / or a new energy passenger vehicle; the driving mode of the new energy vehicle includes pure electric, extended-range electric, hybrid power, fuel cell electric and hydrogen engine.

[0038] On the other hand, the present invention further proposes a machine-readable storage medium, on which instructions are stored, and the instructions are used to enable a machine to execute: the method for controlling a work vehicle according to the above-mentioned method.

[0039] A method for controlling a working vehicle of the present invention comprises: obtaining the rated power of the hydraulic system of the working vehicle, the safety power of the hydraulic system and the engine response curve, wherein the engine response curve comprises the initial response power and the response time; determining the initial response power according to the engine speed of the working vehicle, obtaining the response time when the actual power of the hydraulic system is greater than the initial response power, and determining the engine allowable power according to the response time and the engine response curve; determining the power feedforward correction value according to the actual power of the hydraulic system and the allowable power of the engine; obtaining the engine drop ratio and the target drop ratio, and determining the power correction value according to the engine drop ratio and the target drop ratio; determining the maximum power of the hydraulic system according to the rated power of the hydraulic system, the power feedforward correction value and the power correction value; and determining the maximum actual power of the hydraulic system of the working vehicle according to the maximum power of the hydraulic system and the safety power of the hydraulic system. The present invention performs feedforward control on the power of the hydraulic system based on the influence of the engine response curve on the running stability of the vehicle and the engine response characteristics in a targeted manner, so that the change curve of the current power of the system coincides with the response curve of the engine, thereby ensuring the running efficiency and stability of the system, effectively preventing the system from over-adjusting, and improving the control accuracy.

[0040] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings:

[0042] Figure 1 It is a flow chart of a method for controlling a working vehicle of the present invention;

[0043] Figure 2 It is a schematic diagram of the data table corresponding to the engine response curve;

[0044] Figure 3 is a schematic diagram of a control system of the present invention;

[0045] Figure 4 It is a schematic flow chart of an embodiment of the present invention;

[0046] Figure 5 It is a schematic diagram of a device for controlling a working vehicle according to the present invention.

[0047] Description of Reference Numerals

[0048] 1-pressure sensor, 2-engine ECU, 3-control unit, 4-action solenoid valve, 5-power regulation solenoid valve, 100-acquisition module, 200-first processing module, 300-second processing module, 400-third processing module, 500-fourth processing module, 600-fifth processing module. DETAILED DESCRIPTION

[0049] The specific implementation of the embodiment of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the embodiment of the present invention, and is not used to limit the embodiment of the present invention.

[0050] Figure 1 Schematic diagram of a method for controlling a working vehicle according to the present invention. Figure 1 As shown, the method includes: step S101 is to obtain the rated power of the hydraulic system, the safety power of the hydraulic system and the engine response curve of the working vehicle. The engine response curve is a relationship curve between the power, speed and response time of the engine of the working vehicle. The safety power of the hydraulic system is determined according to the current minimum flow of the hydraulic system and the main oil pressure of the hydraulic system.

[0051] The working vehicle includes a hydraulic system and an engine, and the power source of the engine is the hydraulic system. The rated power of the hydraulic system refers to the maximum power that the hydraulic system can stably output under normal working conditions. This power value is usually a fixed value given by the manufacturer in the product manual.

[0052] The safety power of the hydraulic system refers to the maximum load that the hydraulic system can withstand under stable and continuous working conditions. It represents the output power of the hydraulic system that will not cause damage or danger under normal use conditions.

[0053] The engine response curve is a relationship curve between the power, speed and response time of the engine of the working vehicle, such as Figure 2 As shown, the engine response curve shows the corresponding relationship between the initial response power, the nominal maximum power and the speed gear within a certain response time.

[0054] Step S102 is to determine the initial response power according to the engine speed of the working vehicle, obtain the response time when the actual power of the hydraulic system is greater than the initial response power, and determine the engine allowable power according to the response time and the engine response curve.

[0055] Specifically, the method of determining a response initial power according to the engine speed of the working vehicle, obtaining a response time during which the actual power of the hydraulic system is greater than the response initial power, and determining the allowable engine power according to the response time and an engine response curve includes: determining a speed gear according to the engine speed of the working vehicle, and obtaining the response initial power corresponding to the speed gear; obtaining a time interval during which the actual power of the hydraulic system is greater than the response initial power as the response time, and obtaining a unit change in the allowable engine power within the response time at the speed gear; determining the allowable engine power according to the obtained response initial power, response time and unit change: allowable engine power = response initial power + unit change × response time.

[0056] For example, the speed gear is determined according to the engine speed of the working vehicle, and the response initial power corresponding to the speed gear is obtained as 20w. When the actual power of the hydraulic system is greater than 20w, the timing starts and the timing stops when the actual power of the hydraulic system is less than or equal to 20w. The timing interval is the response time.

[0057] When the actual power of the hydraulic system is not greater than the initial response power, the power feedforward correction value is cleared, and the magnitude of the actual power of the hydraulic system and the initial response power is re-determined.

[0058] The present invention accurately identifies the impact of the engine response curve on the vehicle's operating stability, and performs feedforward control on the system power based on the engine response characteristics, so that the current power change curve of the system matches the engine's response curve, thereby ensuring the system's operating efficiency and stability. It has sufficient theoretical basis, high control accuracy and strong principles.

[0059] Step S103 is to determine the power feedforward correction value according to the actual power of the hydraulic system and the allowed power of the engine. Specifically, if the actual power P of the hydraulic system exceeds the allowed power P2 of the engine, the power feedforward correction value P3 is calculated by the difference between the two, otherwise the power feedforward correction value P3 is 0.

[0060] According to a specific implementation, determining the power feedforward correction value based on the actual power of the hydraulic system and the allowed power of the engine includes: the difference between the actual power of the hydraulic system and the allowed power of the engine is the power feedforward correction value.

[0061] Step S104 is to obtain the engine speed drop ratio and the target speed drop ratio, and determine the power correction value according to the engine speed drop ratio and the target speed drop ratio. The engine speed drop ratio refers to the percentage by which the actual engine speed is reduced compared to the expected speed. The greater the engine speed drop percentage, the more serious the engine speed drop. The target speed drop ratio is the speed drop ratio that meets the target requirement.

[0062] According to a specific implementation manner, the obtaining of the engine speed ratio and the target speed ratio, and determining the power correction value based on the engine speed ratio and the target speed ratio, includes: obtaining the changing trend of the engine speed ratio, and determining the target speed ratio trend of the engine based on the engine speed ratio and the target speed ratio, and when the target speed ratio trend does not meet the target requirement, adjusting the power correction value until the target speed ratio trend meets the target requirement.

[0063] Specifically, the method for adjusting the power correction value may be selected from PID dynamic adjustment, and the PID control adopts the form of trend adjustment to correct the maximum power of the system in real time according to the changing trend of the engine speed ratio. The specific method includes: when the engine speed ratio A exceeds the set threshold value A1, the changing trend of the engine speed ratio is judged in real time. If the engine speed ratio A decreases in real time and the changing trend meets the set requirements, the maximum power PID correction value P4 is maintained unchanged; otherwise, the maximum power PID correction value P4 is increased based on the current speed ratio A. When the engine speed ratio A is less than the set threshold value A1 and the maximum power PID correction value P4 is greater than 0, the changing trend of the engine speed ratio A is judged in real time. If the engine speed ratio A increases in real time and the changing trend meets the set requirements, the maximum power PID correction value P4 is maintained unchanged; otherwise, the maximum power PID correction value P4 is reduced based on the current speed ratio.

[0064] The present invention utilizes the PID trend adjustment algorithm to adaptively adjust the system power, which can achieve precise adjustment, effectively prevent system overadjustment, and ensure the operating efficiency and stability of the system. It has the advantages of good control quality, high precision, and strong principle.

[0065] Step S105 is to determine the maximum power of the hydraulic system according to the rated power of the hydraulic system, the power feedforward correction value and the power correction value.

[0066] According to a specific implementation, the maximum power of the hydraulic system is determined according to the rated power of the hydraulic system, the power feedforward correction value and the power correction value, including: the rated power of the hydraulic system is subtracted from the power feedforward correction value and the power correction value to obtain the maximum power of the hydraulic system. For example, the system calculates the maximum power P5 of the hydraulic system in real time through the maximum power initial value P0, the power feedforward correction value P3 and the power correction value P4.

[0067] Step S106 is to determine the maximum actual power of the hydraulic system of the working vehicle according to the maximum power of the hydraulic system and the safety power of the hydraulic system.

[0068] According to a specific implementation, determining the maximum actual power of the hydraulic system of the working vehicle based on the maximum power of the hydraulic system and the safety power of the hydraulic system includes: obtaining the maximum value between the maximum power of the hydraulic system and the safety power of the hydraulic system as the maximum actual power of the hydraulic system of the working vehicle.

[0069] Specifically, if the maximum power of the hydraulic system of the working machine is too small, the action flow will be too low, which may cause the mechanism to reverse and pose a safety hazard. Considering the safety, the present invention adopts the minimum flow protection mode, and determines the minimum safety flow in real time according to the action during the working process of the machine. The current hydraulic system safety power of the working machine can be calculated through the oil pump port pressure and the minimum safety flow, and the maximum actual power of the hydraulic system is controlled not to be greater than the actual allowable power of the engine.

[0070] When the maximum power of the hydraulic system of the working machine is less than the safety power of the hydraulic system, the maximum actual power of the hydraulic system is equal to the safety power of the hydraulic system; otherwise, the maximum actual power of the hydraulic system is equal to the maximum power of the hydraulic system.

[0071] Figure 3 It is a schematic diagram of the control system of the present invention, such as Figure 3As shown, the control system includes a control unit 3, a pressure sensor 1, an engine ECU 2, an action solenoid valve 4 and a power regulating solenoid valve 5. The pressure sensor 1 is installed at the oil pump P port to detect the P port pressure and load conditions. The engine ECU 2 is used to summarize and process engine-related information, and send information such as the engine expected speed, the engine actual speed, and the engine load rate to the control unit 3 through the CAN bus to calculate the current engine speed drop percentage. The control unit 3 monitors all input signals in real time, performs logical operations, outputs the solenoid valves, and detects the output current of the feedback. The action solenoid valve 4 refers to the related solenoid valves of each action of the vehicle, which are used to adjust the flow of each action. The control unit 3 can determine the required flow of the hydraulic action of the vehicle by detecting the feedback current of each action solenoid valve 4. The power regulating solenoid valve 5 is used to adjust the required power of the vehicle hydraulic system, which is divided into two types: direct proportional control and inverse proportional control. The larger the current of the power regulating solenoid valve in the direct proportional form, the greater the maximum allowable power, and the larger the current of the power regulating solenoid valve in the inverse proportional form, the smaller the required power.

[0072] The present invention obtains the allowable engine power of the vehicle at various speeds according to the engine response curve, and then uses a combination of PID trend control and feedforward regulation to perform real-time correction on the system maximum power during the vehicle operation process, thereby achieving smooth and efficient operation of the system.

[0073] The theoretical maximum power allowed by the hydraulic system of the vehicle at each speed is obtained through the engine response curve, and is stored in the control unit 3 as an initial model for power control. At the same time, the response curve of the vehicle engine at different speed gears is obtained through experiments or calibration (the same model of engine only needs to be tested or calibrated once), and is stored in the control unit 3.

[0074] The control unit 3 collects information such as system load, action flow, engine expected speed, engine actual speed, engine load rate, etc. through the pressure sensor 1, engine ECU 2, and action solenoid valve 4, and calculates the engine speed reduction ratio A and the current system power P based on this information.

[0075] During the operation of the vehicle, the rated power P0 of the hydraulic system is first calculated according to the initial model of power control, and the maximum power of the vehicle system is corrected in real time by combining PID trend control with feedforward regulation: when the maximum power of the hydraulic system of the operating machinery is less than the safety power of the hydraulic system, the maximum actual power of the hydraulic system is equal to the safety power of the hydraulic system, otherwise the maximum actual power of the hydraulic system is equal to the maximum power of the hydraulic system. The control unit 3 adjusts the current of the power regulating solenoid valve to ensure that the current power P of the crane does not exceed the maximum actual power P7 of the hydraulic system, thereby achieving smooth and efficient operation of the vehicle and ensuring safety. The specific process is as follows: Figure 4As shown:

[0076] Step 1: After the crane starts running, the limit load adaptive control function is automatically enabled.

[0077] Step 2: The control unit 3 reads the sensor signal and calculates the current power P of the system (ie, the actual power of the hydraulic system).

[0078] Step 3: The control unit 3 reads the power control initial model and the engine response curve in real time.

[0079] Step 4: The control unit 3 determines the response initial power P1 according to the engine response curve.

[0080] Step 5: The control unit 3 determines in real time whether the current system power P is greater than the response initial power P1: if so, it proceeds to step 6; if not, it clears the engine response time and the power feedforward correction value P3, and proceeds to step 7.

[0081] Step 6: Enter the feedforward adjustment mode, record the engine's response time and use it to calculate the maximum power P2 (i.e. the engine's allowed power) allowed by the engine's current response progress. Real-time judgment of whether P is greater than P2: if so, the system calculates the power feedforward correction value P3 based on the difference between P and P2 in real time; if not, the power feedforward correction value P3 is cleared.

[0082] Step 7: The control unit 3 calculates the engine speed ratio R in real time and detects the actual change trend of R.

[0083] Step 8: The control unit 3 determines the target change trend of R based on the engine speed reduction ratio R and the target speed reduction ratio R1.

[0084] Step 9: The control unit 3 determines in real time whether the actual change trend of R meets the target requirement. If so, it goes to step 11; if not, it goes to step 10.

[0085] Step 10: Adjust the power PID correction value P4 (ie, power correction value) through the PID algorithm.

[0086] Step 11: Obtain the system maximum power initial value P0 according to the power control initial model, and calculate the system maximum power calculated value P5 (i.e., the maximum actual power of the hydraulic system) according to P0, P3, and P4.

[0087] Step 12: Determine the minimum safe flow rate of the action according to the current action of the vehicle, and then calculate the minimum safe power P6 of the crane (i.e. the safe power of the hydraulic system) according to the pressure at the P port of the oil pump and the minimum safe flow rate.

[0088] Step 13: If the calculated value of the system maximum power P5 is less than the minimum safe power of the crane P6, the system maximum power P7 is equal to P6, otherwise the system maximum power is equal to P5.

[0089] Step 14: The control unit 3 adjusts the current of the power regulating solenoid valve to ensure that the current power P of the crane does not exceed the maximum power P7.

[0090] The present invention uses a PID trend adjustment algorithm to adaptively adjust the system power. This trend adjustment can achieve precise adjustment, effectively prevent system overadjustment, and ensure the operating efficiency and stability of the system. This method has good control quality and high precision. The present invention accurately identifies the impact of the engine response curve on the vehicle's operating stability, and performs feedforward control on the system power based on the engine response characteristics, so that the change curve of the system's current power matches the engine's response curve, thereby ensuring the system's operating efficiency and ensuring that the vehicle can operate smoothly and efficiently under various load conditions. The present invention is automatically controlled and does not require manual operation, which reduces the difficulty of operation. It can ensure that the vehicle flow can meet the basic requirements of the action under any load conditions, thereby improving safety.

[0091] On the other hand, the present invention also provides a device for controlling a working vehicle, such as Figure 5 As shown, the device includes: an acquisition module 100, which is used to acquire the rated power of the hydraulic system, the safety power of the hydraulic system and the engine response curve of the working vehicle, and the engine response curve includes the response initial power and the response time; a first processing module 200, which is used to acquire the actual power of the hydraulic system, and when the actual power of the hydraulic system is greater than the initial power of the response, the engine allowable power is determined according to the actual power of the hydraulic system, the response time and the engine response curve; a second processing module 300, which is used to determine the power feedforward correction value according to the actual power of the hydraulic system and the engine allowable power; a third processing module 400, which is used to acquire the engine speed drop ratio and the target speed drop ratio, and determine the power correction value according to the engine speed drop ratio and the target speed drop ratio; a fourth processing module 500, which is used to determine the maximum power of the hydraulic system according to the rated power of the hydraulic system, the power feedforward correction value and the power correction value; a fifth processing module 600, which is used to determine the maximum actual power of the hydraulic system of the working vehicle according to the maximum power of the hydraulic system and the safety power of the hydraulic system.

[0092] The engine response curve is a relationship curve between the power, rotation speed and response time of the engine of the working vehicle.

[0093] The first processing module 200 is also used to determine the response initial power according to the engine speed of the working vehicle, obtain the response time when the actual power of the hydraulic system is greater than the response initial power, and determine the engine allowable power according to the response time and the engine response curve.

[0094] The second processing module 300 is further used to obtain the difference between the actual power of the hydraulic system and the allowed power of the engine as the power feedforward correction value.

[0095] The third processing module 400 is also used to obtain the changing trend of the engine speed ratio, determine the target speed ratio trend of the engine according to the engine speed ratio and the target speed ratio, and when the target speed ratio trend does not meet the target requirement, adjust the power correction value until the target speed ratio trend meets the target requirement.

[0096] The fourth processing module 500 is also used to determine the maximum power of the hydraulic system according to the rated power of the hydraulic system, the power feedforward correction value and the power correction value, including: subtracting the power feedforward correction value and the power correction value from the rated power of the hydraulic system to obtain the maximum power of the hydraulic system.

[0097] The fifth processing module 600 is further used to obtain the maximum value between the maximum power of the hydraulic system and the safety power of the hydraulic system as the maximum actual power of the hydraulic system of the working vehicle.

[0098] The device uses the PID trend adjustment algorithm to adaptively adjust the system power. This trend adjustment can achieve precise adjustment, effectively prevent system overadjustment, and ensure the system's operating efficiency and stability. This method has good control quality and high precision. By accurately identifying the impact of the engine response curve on the vehicle's operating stability, and performing feedforward control on the system power based on the engine response characteristics, the system's current power change curve is consistent with the engine's response curve, thereby ensuring the system's operating efficiency and ensuring that the vehicle can operate smoothly and efficiently under various load conditions.

[0099] On the other hand, the present invention also proposes an engineering vehicle, which includes a device for controlling a working vehicle according to the above-mentioned method; the engineering vehicle is a fuel vehicle and / or a new energy vehicle; the new energy vehicle is a new energy working vehicle and / or a new energy passenger vehicle; the driving mode of the new energy vehicle includes pure electric, extended-range electric, hybrid power, fuel cell electric and hydrogen engine.

[0100] On the other hand, the present invention further proposes a machine-readable storage medium, on which instructions are stored, and the instructions are used to enable a machine to execute: the method for controlling a work vehicle according to the above-mentioned method.

[0101] A method for controlling a working vehicle of the present invention comprises: obtaining the rated power of the hydraulic system of the working vehicle, the safety power of the hydraulic system and the engine response curve, wherein the engine response curve comprises the initial response power and the response duration; obtaining the actual power of the hydraulic system, and when the actual power of the hydraulic system is greater than the initial response power, determining the engine allowable power according to the actual power of the hydraulic system, the response duration and the engine response curve; determining the power feedforward correction value according to the actual power of the hydraulic system and the engine allowable power; obtaining the engine drop ratio and the target drop ratio, and determining the power correction value according to the engine drop ratio and the target drop ratio; determining the maximum power of the hydraulic system according to the rated power of the hydraulic system, the power feedforward correction value and the power correction value; determining the maximum actual power of the hydraulic system of the working vehicle according to the maximum power of the hydraulic system and the safety power of the hydraulic system, and controlling the maximum actual power of the hydraulic system to be not greater than the allowable power of the engine. The present invention performs feedforward control on the power of the hydraulic system based on the influence of the engine response curve on the running stability of the vehicle and the engine response characteristics in a targeted manner, so that the change curve of the current power of the system coincides with the response curve of the engine, thereby ensuring the running efficiency and stability of the system, effectively preventing the system from over-adjusting, and improving the control accuracy.

[0102] The optional implementation modes of the embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above implementation modes. Within the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical scheme of the embodiments of the present invention, and these simple modifications all belong to the protection scope of the embodiments of the present invention.

[0103] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not further describe various possible combinations.

[0104] Those skilled in the art can understand that all or part of the steps in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a program, and the program is stored in a storage medium, including a number of instructions to enable a single-chip microcomputer, a chip or a processor to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0105] 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

1. A method for controlling a work vehicle, It is characterized in that The method includes: Obtain the hydraulic system rated power, hydraulic system safety power and engine response curve of the working vehicle; Determine the response initial power according to the engine speed of the working vehicle, obtain the response time when the actual power of the hydraulic system is greater than the response initial power, and determine the engine allowable power according to the response time and the engine response curve; Determining a power feedforward correction value according to the actual power of the hydraulic system and the allowable power of the engine; Obtaining an engine speed drop ratio and a target speed drop ratio, and determining a power correction value according to the engine speed drop ratio and the target speed drop ratio; Determine the maximum power of the hydraulic system based on the rated power of the hydraulic system, the power feedforward correction value and the power correction value; The maximum actual power of the hydraulic system of the working vehicle is determined according to the maximum power of the hydraulic system and the safety power of the hydraulic system.

2. The method according to claim 1, It is characterized in that The engine response curve is a relationship curve between the power, speed and response time of the engine of the working vehicle; The safety power of the hydraulic system is determined according to the current minimum flow rate of the hydraulic system and the main oil pressure of the hydraulic system.

3. The method according to claim 1, It is characterized in that The method of determining the initial response power according to the engine speed of the working vehicle, obtaining the response time when the actual power of the hydraulic system is greater than the initial response power, and determining the allowable engine power according to the response time and the engine response curve includes: Determining a speed gear according to the engine speed of the working vehicle, and obtaining a response initial power corresponding to the speed gear; The time interval during which the actual power of the hydraulic system is greater than the initial response power is obtained as the response time; Obtaining a unit change in the allowable power of the engine within a response time at the speed gear; The engine allowable power is determined according to the obtained response initial power, response duration and unit change: Engine allowable power = response initial power + unit change × response time.

4. The method according to claim 1, It is characterized in that Determining the power feedforward correction value according to the actual power of the hydraulic system and the allowed power of the engine includes: The difference between the actual power of the hydraulic system and the allowed power of the engine is the power feedforward correction value.

5. The method according to claim 1, It is characterized in that The obtaining of the engine speed drop ratio and the target speed drop ratio, and determining the power correction value according to the engine speed drop ratio and the target speed drop ratio, comprises: Obtain a change trend of the engine speed ratio, determine a target speed ratio trend of the engine according to the engine speed ratio and a target speed ratio, and when the target speed ratio trend does not meet the target requirement, adjust the power correction value until the target speed ratio trend meets the target requirement.

6. The method according to claim 1, It is characterized in that Determining the maximum power of the hydraulic system according to the rated power of the hydraulic system, the power feedforward correction value and the power correction value includes: The maximum power of the hydraulic system is obtained by subtracting the power feedforward correction value and the power correction value in sequence from the rated power of the hydraulic system.

7. The method according to claim 1, It is characterized in that The step of determining the maximum actual power of the hydraulic system of the working vehicle according to the maximum power of the hydraulic system and the safety power of the hydraulic system includes: The maximum value between the maximum power of the hydraulic system and the safety power of the hydraulic system is the maximum actual power of the hydraulic system of the working vehicle.

8. A device for controlling a working vehicle, It is characterized in that The device includes: An acquisition module, used for acquiring the hydraulic system rated power, hydraulic system safety power and engine response curve of the working vehicle; A first processing module is used to determine a response initial power according to the engine speed of the working vehicle, obtain a response time when the actual power of the hydraulic system is greater than the response initial power, and determine an engine allowable power according to the response time and an engine response curve; A second processing module, used for determining a power feedforward correction value according to the actual power of the hydraulic system and the allowed power of the engine; A third processing module is used to obtain an engine speed drop ratio and a target speed drop ratio, and determine a power correction value according to the engine speed drop ratio and the target speed drop ratio; A fourth processing module, used for determining the maximum power of the hydraulic system according to the rated power of the hydraulic system, the power feedforward correction value and the power correction value; The fifth processing module is used to determine the maximum actual power of the hydraulic system of the working vehicle according to the maximum power of the hydraulic system and the safety power of the hydraulic system.

9. An engineering vehicle, It is characterized in that The engineering vehicle comprises the device for controlling an engineering vehicle according to claim 8; The engineering vehicle is a fuel vehicle and / or a new energy vehicle; The new energy vehicle is a new energy working vehicle and / or a new energy passenger vehicle; The driving modes of the new energy vehicles include pure electric, extended-range electric, hybrid, fuel cell electric and hydrogen engine.

10. A machine-readable storage medium, It is characterized in that The machine-readable storage medium stores instructions for causing the machine to execute: a method for controlling a work vehicle according to any one of claims 1-7.

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