Control Method, Control Device and Positive Flow Excavator for Positive Flow Excavator

Abstract

An embodiment of the present invention provides a control method, a control device and a positive flow excavator for a positive flow excavator, belonging to the field of construction machinery. The positive flow excavator includes a plurality of main pumps and main pump solenoid valves corresponding to the main pumps. The control method for the positive flow excavator includes: determining that the target operation type of the positive flow excavator is a crushing operation; obtaining a preset flow rate of hydraulic oil required for the crushing operation; determining the target flow rates respectively corresponding to the plurality of main pumps according to the preset flow rate; determining the control current corresponding to the main pump solenoid valve according to the target flow rate, so as to control the operation of the main pump solenoid valve according to the control current. The embodiment of the present invention can reduce the loss of hydraulic oil and improve the fuel economy of the excavator.

Description

Technical Field

[0001] The present invention relates to the technical field of construction machinery, and particularly relates to a control method, a control device and a positive flow excavator for a positive flow excavator. Background Art

[0002] When an excavator performs a crushing operation, the system pressure of the hydraulic system usually fluctuates within a large pressure range. Since the hydraulic pump is usually a constant power variable pump, when the system pressure is within the high-pressure range, the flow rate of the hydraulic pump is small, and when the system pressure is within the low-pressure range, the flow rate of the hydraulic pump is large. The flow rate of the hydraulic pump corresponding to the low-pressure range is usually much larger than the flow rate of the hydraulic pump corresponding to the high-pressure range. Therefore, there is a loss of flow rate, resulting in high fuel consumption of the whole machine. Summary of the Invention

[0003] The purpose of the embodiments of the present invention is to provide a control method, a control device, a processor and a positive flow excavator for a positive flow excavator, so as to solve the problem of high fuel consumption of the whole machine existing in the prior art.

[0004] To achieve the above purpose, a first aspect of the embodiments of the present invention provides a control method for a positive flow excavator. The positive flow excavator includes a plurality of main pumps and main pump solenoid valves corresponding to the main pumps. The control method includes:

[0005] Determine that the target operation type of the positive flow excavator is a crushing operation;

[0006] Obtain the preset flow rate of the hydraulic oil required for the crushing operation;

[0007] Determine the target flow rates respectively corresponding to the plurality of main pumps according to the preset flow rate;

[0008] Determine the control current corresponding to the main pump solenoid valve according to the target flow rate, so as to control the operation of the main pump solenoid valve according to the control current.

[0009] In the embodiments of the present invention, the positive flow excavator further includes a control mechanism; determining that the target operation type of the positive flow excavator is a crushing operation includes: obtaining the pilot pressure of the control mechanism; determining that the target operation type of the positive flow excavator is a crushing operation according to the pilot pressure.

[0010] In the embodiments of the present invention, the pilot pressure includes a crushing pilot pressure and a non-crushing pilot pressure; determining that the target operation type of the positive flow excavator is a crushing operation according to the pilot pressure includes: comparing the crushing pilot pressure and the non-crushing pilot pressure with a preset pilot pressure threshold respectively; in the case where the crushing pilot pressure is greater than the preset pilot pressure threshold and the non-crushing pilot pressure is less than the preset pilot pressure threshold, determining that the target operation type of the positive flow excavator is a crushing operation.

[0011] In an embodiment of the present invention, a positive flow excavator includes an engine; obtaining a preset flow rate of hydraulic oil required for a crushing operation includes: obtaining the engine speed of the engine; based on a pre-determined correspondence between the engine speed and the flow rate of the engine, determining the preset flow rate according to the engine speed.

[0012] In an embodiment of the present invention, determining target flow rates respectively corresponding to a plurality of main pumps according to the preset flow rate includes: determining target flow rates respectively corresponding to the plurality of main pumps according to the preset flow rate and preset flow rate ratios respectively corresponding to the plurality of main pumps.

[0013] In an embodiment of the present invention, the positive flow excavator further includes a crushing mechanism, the main pumps include a target main pump and non-target main pumps, the target main pump is connected to the crushing mechanism, and the non-target main pumps are not connected to the crushing mechanism; determining target flow rates respectively corresponding to the plurality of main pumps according to the preset flow rate includes: comparing the first maximum output flow rate of the target main pump with the preset flow rate; in the case where the first maximum output flow rate is greater than or equal to the preset flow rate, determining the second target flow rate corresponding to the non-target main pump as the second minimum output flow rate of the non-target main pump, and determining the first target flow rate corresponding to the target main pump according to the second minimum output flow rate and the preset flow rate; in the case where the first maximum output flow rate is less than the preset flow rate, determining the first target flow rate corresponding to the target main pump as the first maximum output flow rate of the target main pump, and determining the second target flow rate corresponding to the non-target main pump according to the first maximum output flow rate and the preset flow rate.

[0014] In an embodiment of the present invention, determining the first target flow rate corresponding to the target main pump according to the second minimum output flow rate and the preset flow rate includes: in the case where the number of non-target main pumps is 1, determining the first target flow rate corresponding to the target main pump as the difference between the preset flow rate and the second minimum output flow rate; determining the second target flow rate corresponding to the non-target main pump according to the first maximum output flow rate and the preset flow rate includes: in the case where the number of non-target main pumps is 1, determining the second target flow rate corresponding to the non-target main pump as the difference between the preset flow rate and the first maximum output flow rate.

[0015] In an embodiment of the present invention, determining the control current corresponding to the main pump solenoid valve according to the target flow rate includes: obtaining the engine speed of the engine; determining the target displacement corresponding to the main pump according to the target flow rate and the engine speed; based on a pre-determined correspondence between the displacement and the current, determining the control current corresponding to the main pump solenoid valve according to the target displacement.

[0016] In an embodiment of the present invention, after determining the target displacement corresponding to the main pump according to the target flow rate and the engine speed, it further includes: obtaining the main pump pressure corresponding to the main pump; comparing the main pump pressure with a preset calibration pressure range; calibrating the target displacement according to the comparison result to obtain a calibrated target displacement.

[0017] In an embodiment of the present invention, calibrating the target displacement according to the comparison result to obtain the calibrated target displacement includes: when the main pump pressure is greater than the lower pressure threshold of the preset calibration pressure range and less than the upper pressure threshold of the preset calibration pressure range, determining the target displacement calibration coefficient corresponding to the main pump pressure within the preset calibration pressure range according to the main pump pressure, the interval length of the preset calibration pressure range, and the preset displacement calibration coefficient corresponding to the upper pressure threshold of the preset calibration pressure range, where both the target displacement calibration coefficient and the preset displacement calibration coefficient are greater than 1; calibrating the target displacement according to the target displacement calibration coefficient to obtain the calibrated target displacement; when the main pump pressure is greater than or equal to the upper pressure threshold of the preset calibration pressure range, calibrating the target displacement according to the preset displacement calibration coefficient to obtain the calibrated target displacement; when the main pump pressure is less than or equal to the lower pressure threshold of the preset calibration pressure range, not calibrating the target displacement.

[0018] In an embodiment of the present invention, calibrating the target displacement according to the comparison result to obtain the calibrated target displacement includes obtaining the calibrated target displacement according to the following formula:

[0019]

[0020] where q_Temp is the target displacement, q_set is the calibrated target displacement, P_Press is the main pump pressure, Press_Min is the lower pressure threshold of the preset calibration pressure range, Press_Max is the upper pressure threshold of the preset calibration pressure range, and δ is the preset displacement calibration coefficient corresponding to the upper pressure threshold.

[0021] A second aspect of the embodiments of the present invention provides a processor configured to execute the control method for a positive flow excavator as described above.

[0022] A third aspect of the embodiments of the present invention provides a control device for a positive flow excavator. The positive flow excavator includes a plurality of main pumps and main pump solenoid valves corresponding to the main pumps. The control device includes: the processor as described above.

[0023] A fourth aspect of the embodiments of the present invention provides a positive flow excavator, including: a plurality of main pumps; main pump solenoid valves corresponding to the main pumps; and the control device as described above.

[0024] In the above technical solution, by determining that the target operation type of the positive flow excavator is the crushing operation, the preset flow rate of the hydraulic oil required for the crushing operation is obtained, and the target flow rates corresponding to multiple main pumps are determined according to the preset flow rate, so as to determine the control current corresponding to the main pump solenoid valve according to the target flow rate, and control the operation of the main pump solenoid valve according to the control current. When the crushing operation is about to be carried out, the above technical solution determines the preset flow rate required for the crushing operation in advance, and distributes the flow rate to each main pump according to the preset flow rate to determine the target flow rate of each main pump, so as to control the operation of each main pump according to the target flow rate, solving the problem of high fuel consumption of the whole machine in the prior art, realizing the constant flow output of the hydraulic system within the pressure change range during the crushing operation, ensuring both the hydraulic oil flow rate required for the crushing operation and avoiding excessive flow loss in the low-pressure range, reducing the loss of hydraulic oil, and improving the fuel economy of the excavator.

[0025] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent specific implementation part. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings are used to provide a further understanding of the embodiments of the present invention, and constitute a part of the specification, and are used to explain the embodiments of the present invention together with the following specific implementation manners, but do not constitute a limitation to the embodiments of the present invention. In the drawings:

[0027] Figure 1 Schematically shows a flowchart of a control method for a positive flow excavator in an embodiment of the present invention;

[0028] Figure 2 Schematically shows a schematic diagram of the system composition of a positive flow excavator in an embodiment of the present invention;

[0029] Figure 3 Schematically shows a flowchart of calculating the control current of the main pump solenoid valve in an embodiment of the present invention;

[0030] Figure 4 Schematically shows a timing diagram of judging the pilot pressure signal of the crushing operation in an embodiment of the present invention;

[0031] Figure 5 Schematically shows a flowchart of a control method for a positive flow excavator in another embodiment of the present invention;

[0032] Figure 6 Schematically shows a relationship diagram between the calibrated target displacement and the main pump pressure during the crushing operation in an embodiment of the present invention;

[0033] Figure 7 Schematically shows a relationship diagram between the displacement and the current in an embodiment of the present invention;

[0034] Figure 8 Schematically shows the schematic diagram of the relationship between the pilot pressure and the required displacement in an embodiment of the present invention;

[0035] Figure 9 Schematically shows the setting schematic diagram of the required displacement corresponding to the compound action in an embodiment of the present invention. Specific Embodiments

[0036] The following will describe in detail the specific embodiments of the embodiments of the present invention with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for explaining and illustrating the embodiments of the present invention, and are not used to limit the embodiments of the present invention.

[0037] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) involved in the embodiments of the present invention, the directional indications are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0038] In addition, if there are descriptions such as "first", "second", etc. involved in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those skilled in the art can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

[0039] Figure 1 Schematically shows the flow schematic diagram of the control method for a positive flow excavator in an embodiment of the present invention. As Figure 1 shown, in the embodiment of the present invention, a control method for a positive flow excavator is provided. The positive flow excavator includes a plurality of main pumps and main pump solenoid valves corresponding to the main pumps. Taking the application of this control method to a processor as an example for illustration, this control method may include the following steps:

[0040] Step S102, determining that the target operation type of the positive flow excavator is a crushing operation.

[0041] Step S104, obtaining the preset flow rate of the hydraulic oil required for the crushing operation.

[0042] Step S106, determining the target flow rates respectively corresponding to the plurality of main pumps according to the preset flow rate.

[0043] Step S108: Determine the control current corresponding to the main pump solenoid valve according to the target flow rate, so as to control the operation of the main pump solenoid valve according to the control current.

[0044] It can be understood that the operation types of the positive flow excavator may include crushing operations, excavation operations, etc. The target operation type is the operation type that the positive flow excavator will execute at the next moment. The preset flow rate is the hydraulic oil flow rate of the hydraulic system required for the preset crushing operation. The target flow rate is the hydraulic oil flow rate corresponding to each main pump during the crushing operation. The larger the control current of the main pump solenoid valve, that is, the larger the opening of the main pump solenoid valve, the larger the flow rate of the main pump.

[0045] Specifically, the processor can first determine that the target operation type of the positive flow excavator is a crushing operation, which can be determined specifically by the user inputting the operation type or according to other actual operating parameters. Furthermore, the processor can obtain the preset flow rate of the hydraulic oil required for the crushing operation. For example, according to the pre-set table of operation types and preset flow rates, the preset flow rate required for the crushing operation can be determined. Thus, the processor can determine the target flow rate corresponding to each main pump according to the preset flow rate. Specifically, the target flow rate of each main pump can be determined according to different flow distribution strategies. For example, the preset flow rate can be evenly distributed according to the number of main pumps to determine the specific value of the target flow rate of each main pump. After determining the target flow rate of each main pump, the processor can determine the control current corresponding to the main pump solenoid valve according to the target flow rate, so as to control the operation of the main pump solenoid valve according to the control current, thereby achieving the purpose of controlling the flow rate of the main pump. Specifically, according to the pre-determined calculation model of the flow rate of the main pump and the current of the main pump solenoid valve, the corresponding control current can be calculated according to the determined target flow rate.

[0046] The above control method for the positive flow excavator determines that the target operation type of the positive flow excavator is a crushing operation, then obtains the preset flow rate of the hydraulic oil required for the crushing operation, and determines the target flow rate corresponding to each main pump according to the preset flow rate, so as to determine the control current corresponding to the main pump solenoid valve according to the target flow rate, and control the operation of the main pump solenoid valve according to the control current. The above technical solution, when about to perform a crushing operation, determines the preset flow rate required for the crushing operation in advance, distributes the flow rate to each main pump according to the preset flow rate to determine the target flow rate of each main pump, and thus controls the operation of each main pump according to the target flow rate, solving the problem of high fuel consumption of the whole machine in the prior art, realizing the constant flow output of the hydraulic system within the pressure change range during the crushing operation, ensuring both the hydraulic oil flow rate required for the crushing operation and avoiding excessive flow loss in the low-pressure range, reducing the loss of hydraulic oil, and improving the fuel economy of the excavator.

[0047] In one embodiment, the positive flow excavator further includes a control mechanism; determining that the target operation type of the positive flow excavator is a crushing operation includes: obtaining the pilot pressure of the control mechanism; and determining that the target operation type of the positive flow excavator is a crushing operation based on the pilot pressure.

[0048] It can be understood that the control mechanism is a mechanism for inputting operation instructions, and may include, for example, a crushing pedal. The pilot pressure of the control mechanism can be obtained through a pilot pressure sensor.

[0049] Specifically, the processor can obtain the pilot pressure of the control mechanism through the pilot pressure sensor, and determine that the target operation type of the positive flow excavator is a crushing operation based on the pilot pressure of the crushing pedal. For example, the processor can obtain the pilot pressure of the crushing pedal, and when the pilot pressure of the crushing pedal is greater than a certain pilot pressure value, the processor can determine that the target operation type of the positive flow excavator is a crushing operation.

[0050] In one embodiment, the pilot pressure includes a crushing pilot pressure and a non-crushing pilot pressure; determining that the target operation type of the positive flow excavator is a crushing operation based on the pilot pressure includes: comparing the crushing pilot pressure and the non-crushing pilot pressure with a preset pilot pressure threshold respectively; and determining that the target operation type of the positive flow excavator is a crushing operation when the crushing pilot pressure is greater than the preset pilot pressure threshold and the non-crushing pilot pressure is less than the preset pilot pressure threshold.

[0051] It can be understood that since the control mechanism may include, in addition to the crushing pedal, a crushing pedal, a left joystick, a right joystick, a left travel pedal, and a right travel pedal, etc., the pilot pressure can include a crushing pilot pressure and a non-crushing pilot pressure. The crushing pilot pressure is the pilot pressure of the crushing pedal, and the non-crushing pilot pressure is the pilot pressure of other control mechanisms except the crushing pedal. The number of non-crushing pilot pressures can be multiple, and specifically can include the pilot pressure for bucket stick in, the pilot pressure for bucket stick out, the slewing pilot pressure, the left travel pilot pressure, the right travel pilot pressure, the boom raise pilot pressure, the boom lower pilot pressure, the bucket in pilot pressure, and the bucket out pilot pressure, etc. Further, the non-crushing pilot pressure can be obtained through corresponding pilot pressure sensors. For example, the pilot pressure for bucket stick in can be obtained through a bucket stick in pilot pressure sensor, and the pilot pressure for bucket stick out can be obtained through a bucket stick out pilot pressure sensor. The preset pilot pressure threshold is a preset pilot pressure threshold.

[0052] Specifically, the processor can compare the crushing pilot pressure and the non-crushing pilot pressure with the preset pilot pressure threshold respectively, and when the crushing pilot pressure is greater than the preset pilot pressure threshold and the non-crushing pilot pressure is less than the preset pilot pressure threshold, the processor can determine that the target operation type of the positive flow excavator is a crushing operation.

[0053] In one embodiment, a positive flow excavator includes an engine; obtaining a preset flow rate of hydraulic oil required for a crushing operation, including: obtaining the engine speed of the engine; and determining the preset flow rate according to the engine speed based on a pre-determined correspondence relationship between the engine speed and the flow rate.

[0054] It can be understood that the engine speed can be obtained by a speed sensor or by an engine controller. The correspondence relationship between the engine speed and the flow rate is a pre-determined and stored correspondence relationship between different engine speeds and the flow rates of hydraulic oil required for the crushing operation corresponding to each engine speed, and can be stored in the form of a table, for example. Further, the engine speed can be divided into multiple gears, and the flow rates of hydraulic oil required for the crushing operation corresponding to each gear can be determined, so as to obtain the correspondence relationship between the engine speed and the flow rate.

[0055] Specifically, the processor can obtain the engine speed of the engine, and based on the pre-determined correspondence relationship between the engine speed and the flow rate, such as a relationship table of engine speed - engine speed gear - flow rate, the processor can look up this relationship table according to the engine speed, so as to determine the preset flow rate required for the crushing operation corresponding to this engine speed.

[0056] In one embodiment, determining the target flow rates respectively corresponding to multiple main pumps according to the preset flow rate includes: determining the target flow rates respectively corresponding to multiple main pumps according to the preset flow rate and the preset flow rate ratios respectively corresponding to the multiple main pumps.

[0057] It can be understood that the preset flow rate ratio is a pre-determined preset flow rate distribution ratio of each main pump. For example, when the number of main pumps is two, the preset flow rate ratios of the two main pumps can be 5:5 (i.e., each of the two main pumps accounts for 50%), or 4:6, or 3:7, etc. When the number of main pumps is three, the preset flow rate ratios of the three main pumps can be 3:3:4, etc.

[0058] Specifically, the processor can determine the product value of the determined preset flow rate and the preset flow rate ratios respectively corresponding to each main pump, so as to determine the target flow rates respectively corresponding to each main pump.

[0059] In one embodiment, the main pumps include a first main pump and a second main pump. The first main pump is connected to the boom, the arm, and the bucket, and the second main pump is connected to the boom, the arm, and the crushing mechanism. The first preset flow rate ratio corresponding to the first main pump is less than or equal to the second preset flow rate ratio corresponding to the second main pump, and the sum value of the first preset flow rate ratio and the second preset flow rate ratio is 100%.

[0060] It can be understood that the crushing mechanism is a functional component that performs specific crushing operations, such as a hydraulic breaker. Usually, during the crushing operation, the operator needs to operate the control mechanism (such as the crushing pedal) to make the crushing mechanism (such as the hydraulic breaker) work. The preset flow rate ratio corresponding to the first main pump is the first preset flow rate ratio, and the preset flow rate ratio corresponding to the second main pump is the second preset flow rate ratio. Since the second main pump is connected to the crushing mechanism and the first main pump is not connected to the crushing mechanism, usually, during the crushing operation, the hydraulic oil flow rate required by the crushing mechanism is greater than that required by other actuators (such as the boom and the stick). Therefore, the second preset flow rate ratio is usually greater than the first preset flow rate ratio, and the sum of the two is 100%. For example, the second preset flow rate ratio is 70% and the first preset flow rate ratio is 30%.

[0061] In one embodiment, the positive flow excavator further includes a crushing mechanism. The main pumps include a target main pump and a non-target main pump. The target main pump is directly connected to the crushing mechanism, and the non-target main pump is not directly connected to the crushing mechanism. Determining the target flow rates corresponding to the multiple main pumps according to the preset flow rate includes: comparing the first maximum output flow rate of the target main pump with the preset flow rate; in the case where the first maximum output flow rate is greater than or equal to the preset flow rate, determining the second target flow rate corresponding to the non-target main pump as the second minimum output flow rate of the non-target main pump, and determining the first target flow rate corresponding to the target main pump according to the second minimum output flow rate and the preset flow rate; in the case where the first maximum output flow rate is less than the preset flow rate, determining the first target flow rate corresponding to the target main pump as the first maximum output flow rate of the target main pump, and determining the second target flow rate corresponding to the non-target main pump according to the first maximum output flow rate and the preset flow rate.

[0062] It can be understood that the target main pump is the main pump connected to the crushing mechanism, and the non-target main pump is the main pump not connected to the crushing mechanism. The number of non-target main pumps can be one or more. The first maximum output flow rate is the maximum flow rate that the target main pump can provide. The second minimum output flow rate is the minimum flow rate that the non-target main pump can provide. The first target flow rate is the target flow rate corresponding to the target main pump. The second target flow rate is the target flow rate corresponding to the non-target main pump. In some other embodiments, the crushing mechanism can be supplied with oil through a flow combining valve, and the flow combining valve is configured as a solenoid valve. When the solenoid valve is energized, it is in the flow combining open state, that is, double pumps supply oil for crushing. When the solenoid valve is not energized, it is in the non-flow combining state, that is, single pump supplies oil for crushing.

[0063] Specifically, after determining the target main pump, the processor can compare the first maximum output flow rate of the target main pump with a preset flow rate. When it is determined that the first maximum output flow rate is greater than or equal to the preset flow rate, that is, the target main pump alone can meet the demand of the preset flow rate. At this time, the processor can determine the second target flow rate corresponding to the non-target main pump as the second minimum output flow rate of the non-target main pump, and determine the first target flow rate corresponding to the target main pump according to the second minimum output flow rate and the preset flow rate. Specifically, the first target flow rate corresponding to the target main pump can be determined according to the number of non-target main pumps, the second minimum output flow rate of the non-target main pumps, and the preset flow rate. For example, when the number of non-target main pumps is multiple, the processor can subtract the second minimum output flow rate corresponding to each non-target main pump from the preset flow rate to obtain the first target flow rate corresponding to the target main pump. Further, when it is determined that the first maximum output flow rate is less than the preset flow rate, that is, the target main pump outputting the maximum flow rate still cannot meet the demand of the preset flow rate, the processor can determine the first target flow rate corresponding to the target main pump as the first maximum output flow rate of the target main pump, and determine the second target flow rate corresponding to the non-target main pump according to the first maximum output flow rate and the preset flow rate. Specifically, the second target flow rate corresponding to the non-target main pump can be determined according to the number of non-target main pumps, the first maximum output flow rate, and the preset flow rate. For example, when the number of non-target main pumps is multiple, the processor can subtract the first maximum output flow rate from the preset flow rate to obtain the difference between the two, and evenly distribute this difference to obtain the second target flow rate corresponding to each non-target main pump. Further, in some embodiments, the processor can also determine the priority of each non-target main pump and determine the second target flow rate of each non-target main pump according to the priority.

[0064] In one embodiment, determining the first target flow rate corresponding to the target main pump according to the second minimum output flow rate and the preset flow rate includes: when the number of non-target main pumps is 1, determining the first target flow rate corresponding to the target main pump as the difference between the preset flow rate and the second minimum output flow rate.

[0065] Specifically, when the number of non-target main pumps is 1 and the first maximum output flow rate is greater than or equal to the preset flow rate, the processor can determine that the non-target main pump outputs its minimum output flow rate, that is, the second minimum output flow rate, and determine the first target flow rate corresponding to the target main pump as the difference between the preset flow rate and the second minimum output flow rate.

[0066] In one embodiment, determining the second target flow rate corresponding to the non-target main pump according to the first maximum output flow rate and the preset flow rate includes: when the number of non-target main pumps is 1, determining the second target flow rate corresponding to the non-target main pump as the difference between the preset flow rate and the first maximum output flow rate.

[0067] Specifically, when the number of non-target main pumps is 1 and the first maximum output flow rate is less than the preset flow rate, the processor may determine that the target main pump outputs its maximum available output flow rate, i.e., the first maximum output flow rate, and determine that the second target flow rate corresponding to the non-target main pump is the difference between the preset flow rate and the first maximum output flow rate.

[0068] In one embodiment, determining the control current corresponding to the main pump solenoid valve according to the target flow rate includes: obtaining the engine speed of the engine; determining the target displacement corresponding to the main pump according to the target flow rate and the engine speed; and determining the control current corresponding to the main pump solenoid valve according to the target displacement based on the pre-determined corresponding relationship between the displacement and the current.

[0069] Specifically, the processor may obtain the engine speed of the engine and determine the target displacement corresponding to the main pump according to the target flow rate and the engine speed. Specifically, it may be based on the pre-set relationship formula among the flow rate, the speed, and the displacement (wherein, the displacement is proportional to the flow rate and inversely proportional to the engine speed), determine the target displacement corresponding to the main pump according to the target flow rate and the engine speed, and determine the control current corresponding to the main pump solenoid valve according to the target displacement based on the pre-determined corresponding relationship between the displacement and the current, such as a linearly proportional relationship.

[0070] In one embodiment, determining the target displacement corresponding to the main pump according to the target flow rate and the engine speed includes determining according to the following formula:

[0071]

[0072] wherein, q_Temp is the target displacement, Q_Set is the target flow rate, and n is the engine speed.

[0073] In one embodiment, the pre-determined corresponding relationship between the displacement and the current may include the following formula:

[0074]

[0075] wherein, set_Current is the current, q_Set is the displacement, q_Min is the lower displacement threshold of the preset displacement range, and q_Max is the upper displacement threshold of the preset displacement range.

[0076] It can be understood that when the displacement of the main pump is less than the lower displacement threshold of the preset displacement range, the current of the main pump solenoid valve corresponding to the main pump may be 0; when the displacement of the main pump is greater than or equal to the upper displacement threshold of the preset displacement range, the current of the main pump solenoid valve corresponding to the main pump may be 700 mA; when the displacement of the main pump is greater than or equal to the lower displacement threshold of the preset displacement range and less than the upper displacement threshold of the preset displacement range, the current of the main pump solenoid valve corresponding to the main pump may be calculated linearly as above.

[0077] As the pressure increases, the volumetric efficiency of the main pump decreases to a certain extent. To keep the output flow rate stable at the set value, it is necessary to calibrate the target displacement. In one embodiment, after determining the target displacement corresponding to the main pump according to the target flow rate and the engine speed, it further includes: obtaining the main pump pressure corresponding to the main pump; comparing the main pump pressure with a preset calibration pressure range; and calibrating the target displacement according to the comparison result to obtain the calibrated target displacement.

[0078] It can be understood that the main pump pressure can be obtained by a pressure detection device such as a pressure sensor. The preset calibration pressure range is the main pump pressure range for which displacement calibration needs to be performed and is set in advance.

[0079] Specifically, the processor can obtain the main pump pressure corresponding to the main pump, compare the main pump pressure with the preset calibration pressure range, and calibrate the target displacement according to the comparison result to obtain the calibrated target displacement.

[0080] In one embodiment, calibrating the target displacement according to the comparison result to obtain the calibrated target displacement includes: when the main pump pressure is greater than the lower pressure threshold of the preset calibration pressure range and less than the upper pressure threshold of the preset calibration pressure range, determining the target displacement calibration coefficient corresponding to the main pump pressure within the preset calibration pressure range according to the main pump pressure, the interval length of the preset calibration pressure range, and the preset displacement calibration coefficient corresponding to the upper pressure threshold of the preset calibration pressure range, where both the target displacement calibration coefficient and the preset displacement calibration coefficient are greater than 1; calibrating the target displacement according to the target displacement calibration coefficient to obtain the calibrated target displacement; when the main pump pressure is greater than or equal to the upper pressure threshold of the preset calibration pressure range, calibrating the target displacement according to the preset displacement calibration coefficient to obtain the calibrated target displacement; and when the main pump pressure is less than or equal to the lower pressure threshold of the preset calibration pressure range, not calibrating the target displacement.

[0081] It can be understood that the preset displacement calibration coefficient is the displacement calibration coefficient corresponding to the upper pressure threshold of the preset calibration pressure range set in advance, such as 1.2, etc. The target displacement calibration coefficient is the displacement calibration coefficient corresponding to the main pump pressure, such as 1.15, etc.

[0082] Specifically, when the main pump pressure is within the preset calibration pressure range, the processor can determine the target displacement calibration coefficient corresponding to the main pump pressure within the preset calibration pressure range according to the main pump pressure, the length of the preset calibration pressure range, and the preset displacement calibration coefficient corresponding to the upper pressure threshold of the preset calibration pressure range. Specifically, it can be obtained through linear calculation. Furthermore, the target displacement can be calibrated according to the target displacement calibration coefficient to obtain the calibrated target displacement. For example, the target displacement calibration coefficient (such as 1.15) is multiplied by the target displacement to obtain the calibrated target displacement. When the main pump pressure is greater than or equal to the upper pressure threshold of the preset calibration pressure range, the processor can calibrate the target displacement according to the preset displacement calibration coefficient to obtain the calibrated target displacement, that is, the processor can multiply the preset displacement calibration coefficient (such as 1.2) by the target displacement to obtain the calibrated target displacement. When the main pump pressure is less than or equal to the lower pressure threshold of the preset calibration pressure range, the processor can not calibrate the target displacement.

[0083] In one embodiment, calibrating the target displacement according to the comparison result to obtain the calibrated target displacement includes obtaining the calibrated target displacement according to the following formula:

[0084]

[0085] where q_Temp is the target displacement, q_set is the calibrated target displacement, P_Press is the main pump pressure, Press_Min is the lower pressure threshold of the preset calibration pressure range, Press_Max is the upper pressure threshold of the preset calibration pressure range, and δ is the preset displacement calibration coefficient corresponding to the upper pressure threshold.

[0086] The crushing operation is one of the most common working conditions of an excavator. To achieve the flow matching in the crushing mode, the prior art usually sets the B (Breaking Brake) mode and sets different rotational speed and power values in the B mode from those in the excavation mode.

[0087] Generally, when the breaker strikes, the system pressure will fluctuate within the range of 20 - 35 Mpa. At the same time, to meet the working requirements of the breaker, the system needs to meet the required flow at 30 Mpa. In the prior art, whether in the excavation mode or the crushing mode, constant power control is generally adopted, and the required flow at 30 Mpa is met through the power setting in the B mode. According to the constant power model, when the pressure is low, the flow rate is much higher than the required flow at 30 Mpa, resulting in a large amount of flow loss and thus high fuel consumption of the whole machine.

[0088] Figure 2 Schematically shows a schematic diagram of the system composition of a positive flow excavator according to an embodiment of the present invention. As Figure 2As shown in the figure, the positive flow excavator mainly includes a left joystick 101, a left travel pedal 102, a right travel pedal 103, a right joystick 104, a breaker pedal 105, a pilot pressure sensor group 200 (where 200-1 is the boom inwards pressure sensor, 200-2 is the boom outwards pressure sensor, 200-3 is the slewing pressure sensor, 200-4 is the left travel pressure sensor, 200-5 is the right travel pressure sensor, 200-6 is the boom lift pressure sensor, 200-7 is the boom lower pressure sensor, 200-8 is the bucket inwards pressure sensor, 200-9 is the bucket outwards pressure sensor, 200-10 is the breaker pressure sensor), a main pump 1 pressure sensor 201, a main pump 2 pressure sensor 202, a main pump 1 solenoid valve 203, a main pump 2 solenoid valve 204, main pumps 205, 206, a main control valve group 300, a boom cylinder 301, a stick cylinder 302, a bucket cylinder 303, a slewing motor 304, a breaker 305, a display 401, a controller 402, an engine controller 403, and an engine 404.

[0089] A specific embodiment of the present invention provides a control method for a positive flow excavator, as Figure 3 shown. By collecting the pilot pressure of the control handle and the pilot pressure of the breaker foot pedal through the controller, different actions are identified, and dynamic adjustment of power distribution is achieved according to different actions and loads. Constant flow control is performed during breaker operations, and constant power control is performed during non-breaker actions, taking into account fuel consumption and operation efficiency while ensuring controllability.

[0090] 1. Action identification

[0091] By collecting the signals of the pilot pressure sensor group 200 through the controller 402, the breaker single action is identified. The signal timing diagram for judgment is as Figure 4 shown. By collecting the signals of the pilot pressure sensor group 200 through the controller 402, usually the range of each pilot pressure is 0-40 bar, and the opening pressure of the spool is 7-10 bar. When there is no action and the handle is not manipulated, the pilot pressure is 0. Therefore, when the breaker pilot pressure is higher than 5 bar and all other pilot pressures are less than 5 bar, the controller determines the current state as the breaker single action.

[0092] 2. Control under non-breaker actions

[0093] Constant power control is adopted under non-breaker actions, which will be introduced in detail later.

[0094] 3. Control under breaker actions

[0095] 3.1 Mode judgment

[0096] The present invention provides two constant flow control strategies, namely, the control strategy of averaging the flow rates of two pumps and the control strategy with priority given to pump 2, where pump 2 is the main pump connected to the breaker.

[0097] 3.2 Flow rate setting

[0098] Compared with the prior art, on the basis of setting each mode and gear, the flow rate parameters for each gear in the crushing mode are added.

[0099]

[0100]

[0101] Taking the machine operating in the 10th gear of the crushing mode as an example, the total preset flow rate value of pumps P1 and P2 is taken as Q_SetB10. As shown in the appendix Figure 5 shown, the calculation method is as follows:

[0102] (1) Dual-pump averaging mode

[0103] Q1_Set = Q_SetB10 / 2

[0104] Q2_Set = Q_SetB10 / 2

[0105] Among them, Q1_Set is the target flow rate of pump 1 (i.e., the set displacement in Figure 5 ), Q2_Set is the target flow rate of pump 2, and Q_SetB10 is the preset flow rate.

[0106] (2) Pump 2 priority mode

[0107] When Q_Set < (Q_Max - Q_Min), that is, a single pump 2 can meet the flow rate requirement (i.e., the preset flow rate requirement), then pump 1 outputs the minimum flow rate and pump 2 adjusts dynamically.

[0108] Q1_Set = Q_Min

[0109] Q2_Set = Q_Set - Q_Min

[0110] When Q_Set ≥ (Q_Max - Q_Min), that is, the maximum flow rate output by pump 2 still cannot meet the flow rate requirement, then the insufficient part is made up by pump 1.

[0111] Q1_Set = Q_Set - Q_Max

[0112] Q2_Set = Q_Max

[0113] Q_Max refers to the maximum flow rate provided by a single pump, and Q_Min refers to the minimum flow rate provided by a single pump

[0114] In specific applications, the mode to be adopted can be selected through the display.

[0115] 3.3 Target Displacement Setting

[0116] Target displacement of pump 1:

[0117] Target displacement of pump 2:

[0118] Where: n is the engine speed, q1_Temp is the target displacement of pump 1, Q1_Set is the target flow rate of pump 1, q2_Temp is the target displacement of pump 2, and Q2_Set is the target flow rate of pump 2.

[0119] 3.4 Target Displacement Calibration

[0120] As the pressure increases, the volumetric efficiency of the main pump decreases to a certain extent. To keep the output flow rate stable at the set value, this method adopts a pressure-based calibration method, as Figure 6 shown.

[0121]

[0122]

[0123] Where, P1_Press is the pressure of main pump 1, P2_Press is the pressure of main pump 2, δ is the calibration percentage, and its value range can be 110%-120%, Press_Min is the starting calibration pressure, and its value range can be 15 Mpa - 20 Mpa, Press_Max is the maximum calibration pressure, and its value range can be 25 Mpa - 35 Mpa.

[0124] 3.5 Calculation of Control Current of Main Pump Solenoid Valve

[0125] As Figure 7 shown, the control current of pump 1:

[0126]

[0127] Where, set_Current1 is the current, q1_ is the displacement, q_Min is the lower displacement threshold of the preset displacement range, and q_Max is the upper displacement threshold of the preset displacement range.

[0128] Control current of pump 2:

[0129]

[0130] Where, ser_Current2 is the current, q2_ is the displacement, q_Min is the lower displacement threshold of the preset displacement range, and q_Max is the upper displacement threshold of the preset displacement range.

[0131] The specific process of constant power control is introduced as follows:

[0132] (1) Calculation of the required displacement of pump 1 during single action

[0133] As Figure 8 shown, when the pilot pressure is less than the corresponding spool start opening pressure Pilot_Min, the required displacement q1 is set to 0%, when the pilot pressure is greater than the corresponding spool full opening pressure Pilot_Max, the pilot pressure corresponding required displacement q1 is set to 100%, and when the pilot pressure is between Pilot_Min and Pilot_Max, the required displacement q1 is obtained through linearization calculation.

[0134] (2) Calculation of the pilot pressure corresponding required displacement q1 of pump 1 during combined action

[0135] As Figure 9 shown, the required displacement q1 of pump 1 is determined by the pilot pressures such as the left travel pilot pressure, boom lift pilot pressure, boom lower pilot pressure, bucket excavation pilot pressure, bucket discharge pilot pressure, stick in pilot pressure, and stick out pilot pressure. During combined action, first calculate the required displacement of single action, and then calculate the required displacement q1 of combined action according to f(x). Usually, f(x) is directly calculated by taking the maximum value, that is, the maximum value among multiple single action required displacements is selected as the required displacement q1 of combined action.

[0136] (3) Calculation of the pilot pressure corresponding required displacement q2 of pump 2

[0137] The required displacement of pump 2 is determined by the pilot pressures such as the right travel pilot pressure, swing pilot pressure, boom lift pilot pressure, boom lower pilot pressure, stick in pilot pressure, stick out pilot pressure, and breaker pilot pressure. The calculation method is the same as that of the required displacement of pump 1.

[0138] (4) Preset power value of the control system

[0139] The controller sets the preset power value parameter according to different working modes, working gears, and working speeds. Taking the machine working in the excavation mode, gear 10 (the gear corresponding to the engine speed) as an example, when the machine is working in gear 10, the total power value of the P1 and P2 double pumps is taken as Power10.

[0140]

[0141]

[0142] (5) Calculate the preset power of each pump by combining the preset power distribution table

[0143] Preset power of Pump 1: Power_Default1 = Power10 * 50%

[0144] Preset power of Pump 2: Power_Default2 = Power10 * 50%

[0145] (6) Calculation of the required power Power_Pilot

[0146] Required power of Pump 1:

[0147] Required power of Pump 2:

[0148] Where n is the engine speed, P1_Press is the pressure of Pump 1, P2_Press is the pressure of Pump 2, q1 is the required displacement of Pump 1, q2 is the required displacement of Pump 2, Power_Pilot1 is the required power of Pump 1, and Power_Pilot2 is the required power of Pump 2.

[0149] (7) Power setting

[0150] The set power of Pump 1 takes the smaller value between the required power Power_Pilot1 of Pump 1 and the preset power Power_Default1 of Pump 1, that is, the set power of Pump 1 Power_Set1 = Min(Power_Pilot1, Power_Default1).

[0151] The set power of Pump 2 takes the smaller value between the required power Power_Pilot2 of Pump 2 and the preset power Power_Default2 of Pump 2, that is, the set power of Pump 2 Power_Set2 = Min(Power_Pilot2, Power_Default2).

[0152] (8) Calculation of the output displacement

[0153] Output displacement of Pump 1:

[0154] Output displacement of Pump 2:

[0155] Where Power_Set1 is the set power of Pump 1, Power_Set2 is the set power of Pump 2, n is the engine speed, P1_Press is the pressure of Pump 1, P2_Press is the pressure of Pump 2, q1_Set is the output displacement of Pump 1, and q2_Set is the output displacement of Pump 2.

[0156] (9) Calculation of the output current

[0157] Refer to Figure 7 , the output current of Pump 1:

[0158]

[0159] Output current of pump 2:

[0160]

[0161] Wherein, set_Current1 and set_Current2 are the output currents of pump 1 and pump 2 respectively, q1_ and q2_ are the output displacements of pump 1 and pump 2 respectively, q_Min is the lower displacement threshold of the preset displacement range, and q_Max is the upper displacement threshold of the preset displacement range.

[0162] In summary, the present invention realizes the constant flow output of the system in all pressure ranges during the crushing operation through two methods of double-pump averaging and pump 2 priority, and combines the displacement calibration method based on pressure. It not only ensures the flow required by the breaker at 30 Mpa, but also avoids the flow loss in the low-pressure range. At the same time, through action recognition, when a non-crushing action is recognized, it automatically switches to constant power control to ensure the controllability during non-crushing actions.

[0163] An embodiment of the present invention provides a processor configured to execute the control method for a positive flow excavator according to the above-mentioned embodiments.

[0164] An embodiment of the present invention provides a control device for a positive flow excavator. The positive flow excavator includes a plurality of main pumps and main pump solenoid valves corresponding to the main pumps. The control device includes: a processor according to the above-mentioned embodiments.

[0165] An embodiment of the present invention provides a positive flow excavator, including: a plurality of main pumps; main pump solenoid valves corresponding to the main pumps; and a control device according to the above-mentioned embodiments.

[0166] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0167] This application is described with reference to the flowcharts and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It should be understood that each flow and / or block in the flowchart and / or block diagram, and the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing device to produce a machine, such that the instructions executed by the processor of the computer or other programmable data processing device generate means for implementing the functions specified in one or more of the flows Figure 1 one or more of the flows and / or blocks Figure 1 or means for implementing the functions specified in one or more of the blocks.

[0168] These computer program instructions can 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, such that the instructions stored in the computer-readable memory produce a manufacture including instruction means that implement the functions specified in one or more of the flows Figure 1 one or more of the flows and / or blocks Figure 1 or means for implementing the functions specified in one or more of the blocks.

[0169] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to produce a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more of the flows Figure 1 one or more of the flows and / or blocks Figure 1 or means for implementing the functions specified in one or more of the blocks.

[0170] In a typical configuration, a computing device includes one or more processors (CPUs), an input / output interface, a network interface, and memory.

[0171] The memory may include non-permanent memory in the form of computer-readable media, random access memory (RAM), and / or non-volatile memory such as read-only memory (ROM) or flash memory (flash RAM). The memory is an example of computer-readable media.

[0172] A computer-readable medium includes permanent and non-permanent, removable and non-removable media that can implement information storage by any method or technology. The 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 technologies, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassette tapes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transitory media that can be used to store information that can be accessed by a computing device. As defined herein, a computer-readable medium does not include transitory computer-readable media, such as modulated data signals and carrier waves.

[0173] It should also be noted that the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element.

[0174] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims

1. A control method for a positive flow excavator, characterized in that The positive flow excavator includes a plurality of main pumps and main pump solenoid valves corresponding to the main pumps. The positive flow excavator further includes an engine. The control method includes: Determine that the target operation type of the positive flow excavator is a crushing operation; Obtain the preset flow rate of the hydraulic oil required for the crushing operation; Determine the target flow rates respectively corresponding to the plurality of main pumps according to the preset flow rate; Determine the control current corresponding to the main pump solenoid valve according to the target flow rate, so as to control the operation of the main pump solenoid valve according to the control current; Wherein, determining the control current corresponding to the main pump solenoid valve according to the target flow rate includes: obtaining the engine speed of the engine; determining the target displacement corresponding to the main pump according to the target flow rate and the engine speed; based on the pre-determined corresponding relationship between displacement and current, determining the control current corresponding to the main pump solenoid valve according to the target displacement; After determining the target displacement corresponding to the main pump according to the target flow rate and the engine speed, it further includes: obtaining the main pump pressure corresponding to the main pump; comparing the main pump pressure with a preset calibration pressure range; calibrating the target displacement according to the comparison result to obtain a calibrated target displacement; Calibrating the target displacement according to the comparison result to obtain a calibrated target displacement includes: In the case where the main pump pressure is greater than the lower pressure threshold of the preset calibration pressure range and less than the upper pressure threshold of the preset calibration pressure range, determine the target displacement calibration coefficient corresponding to the main pump pressure within the preset calibration pressure range according to the main pump pressure, the interval length of the preset calibration pressure range, and the preset displacement calibration coefficient corresponding to the upper pressure threshold of the preset calibration pressure range, wherein both the target displacement calibration coefficient and the preset displacement calibration coefficient are greater than 1; Calibrate the target displacement according to the target displacement calibration coefficient to obtain a calibrated target displacement; In the case where the main pump pressure is greater than or equal to the upper pressure threshold of the preset calibration pressure range, calibrate the target displacement according to the preset displacement calibration coefficient to obtain a calibrated target displacement; In the case where the main pump pressure is less than or equal to the lower pressure threshold of the preset calibration pressure range, do not calibrate the target displacement.

2. The control method according to claim 1, characterized in that, The positive flow excavator further includes a control mechanism; Determining that the target operation type of the positive flow excavator is a crushing operation includes: Obtain the pilot pressure of the control mechanism; Determine that the target operation type of the positive flow excavator is a crushing operation according to the pilot pressure.

3. The control method according to claim 2, characterized in that The pilot pressure includes a crushing pilot pressure and a non-crushing pilot pressure. Determining that the target operation type of the positive flow excavator is a crushing operation according to the pilot pressure includes: Compare the crushing pilot pressure and the non-crushing pilot pressure with a preset pilot pressure threshold respectively; In the case where the crushing pilot pressure is greater than the preset pilot pressure threshold and the non-crushing pilot pressure is less than the preset pilot pressure threshold, determine that the target operation type of the positive flow excavator is a crushing operation.

4. The control method according to claim 1, wherein Obtaining the preset flow rate of the hydraulic oil required for the crushing operation includes: Obtaining the engine speed of the engine; Based on the pre-determined correspondence between the engine speed and the flow rate, determining the preset flow rate according to the engine speed.

5. The control method according to claim 1, wherein Determining the target flow rates corresponding to the multiple main pumps according to the preset flow rate includes: Determining the target flow rates corresponding to the multiple main pumps according to the preset flow rate and the preset flow rate ratios respectively corresponding to the multiple main pumps.

6. The control method according to claim 1, characterized in that The positive flow excavator further includes a crushing mechanism. The main pumps include a target main pump and non-target main pumps. The target main pump is connected to the crushing mechanism, and the non-target main pumps are not connected to the crushing mechanism. Determining the target flow rates corresponding to the multiple main pumps according to the preset flow rate includes: Comparing the first maximum output flow rate of the target main pump with the preset flow rate; When the first maximum output flow rate is greater than or equal to the preset flow rate, determining the second target flow rate corresponding to the non-target main pump as the second minimum output flow rate of the non-target main pump, and determining the first target flow rate corresponding to the target main pump according to the second minimum output flow rate and the preset flow rate; When the first maximum output flow rate is less than the preset flow rate, determining the first target flow rate corresponding to the target main pump as the first maximum output flow rate of the target main pump, and determining the second target flow rate corresponding to the non-target main pump according to the first maximum output flow rate and the preset flow rate.

7. The control method according to claim 6, wherein Determining the first target flow rate corresponding to the target main pump according to the second minimum output flow rate and the preset flow rate includes: When the number of non-target main pumps is 1, determining the first target flow rate corresponding to the target main pump as the difference between the preset flow rate and the second minimum output flow rate; Determining the second target flow rate corresponding to the non-target main pump according to the first maximum output flow rate and the preset flow rate includes: When the number of non-target main pumps is 1, determining the second target flow rate corresponding to the non-target main pump as the difference between the preset flow rate and the first maximum output flow rate.

8. The control method according to claim 1, characterized in that Calibrating the target displacement according to the comparison result to obtain the calibrated target displacement includes obtaining the calibrated target displacement according to the following formula: Wherein, is the target displacement, is the calibrated target displacement, is the main pump pressure, is the lower pressure threshold of the preset calibration pressure range, is the upper pressure threshold of the preset calibration pressure range, is the preset displacement calibration coefficient corresponding to the upper pressure threshold.

9. A processor, characterized in that, Configured to execute the control method for a positive flow excavator according to any one of claims 1 to 8.

10. A control device for a positive flow excavator, characterized in that, The positive flow excavator includes a plurality of main pumps and main pump solenoid valves corresponding to the main pumps. The positive flow excavator further includes an engine. The control device includes: The processor according to claim 9.

11. A positive flow excavator, characterized in that, Including: A plurality of main pumps; Main pump solenoid valves corresponding to the main pumps; An engine; And The control device according to claim 10.

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