Method and device for automatic calibration of a hydraulic system, and engineering machine

Abstract

The application discloses an automatic calibration method and device of a hydraulic system and engineering machinery. Based on each control point of a control curve, a target proportional valve of a hydraulic system to be calibrated is opened, and a target current value of the target proportional valve and a corresponding main pump pressure value are obtained. A relative pressure difference value between adjacent main pump pressure values is calculated. When the relative pressure difference value meets a series of standards, a relative current difference value between adjacent target current values is calculated. According to the relative current difference value and a standard current difference value, the control curve of the hydraulic system to be calibrated is calibrated. That is, in the calibration process, on the premise that the relative pressure difference value meets a series of standards determined by a standard pressure difference value, the relative current difference value between adjacent target current values is calculated, the relative current difference value and the standard current difference value are analyzed, and the control curve of the hydraulic system is calibrated, so that the output effect of the engineering machinery approaches an expected standard, and the consistency and reliability of the engineering machinery are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of calibration of hydraulic systems, and in particular to an automatic calibration method and device for a hydraulic system and engineering machinery. BACKGROUND

[0002] Important components of the hydraulic system of engineering machinery include hydraulic pumps, hydraulic motors and valves, and the relationship between the displacement of the hydraulic pump and the control current is not fixed. Errors are generated in the production, manufacture, assembly of the main valve and hydraulic pump in the hydraulic circuit, and the assembly with the hydraulic pipeline and the actuator, and the superposition of errors leads to obvious performance differences in engineering machinery with the same configuration, especially in the process of promoting from a prototype machine to a production machine, a large amount of manpower and time is still needed to find the cause of the problem.

[0003] To solve the above problems, the existing solution is mainly to take the main pressure of the hydraulic pump as the basis to calibrate the engineering machinery at a single point. Single-point calibration is easily affected by the hydraulic oil temperature, ambient temperature and atmospheric pressure, and has small calibration data, low calibration precision and accuracy. SUMMARY

[0004] The present application provides an automatic calibration method and device for a hydraulic system and engineering machinery to solve the defects in the prior art that single-point calibration is easily affected by the hydraulic oil temperature, ambient temperature and atmospheric pressure, and has small calibration data, low calibration precision and accuracy.

[0005] According to one aspect of the present application, an automatic calibration method for a hydraulic system is provided, comprising: based on each control point of a control curve, controlling a target proportional valve of a hydraulic system to be calibrated to open and obtaining a target current value and a corresponding main pump pressure value of the target proportional valve; calculating a relative pressure difference value between adjacent main pump pressure values; when the relative pressure difference value meets a series of standards, calculating a relative current difference value between adjacent target current values; wherein the series of standards is obtained based on a standard pressure difference value; and calibrating the control curve of the hydraulic system to be calibrated according to the relative current difference value and a standard current difference value.

[0006] In an embodiment, the calibration of the control curve of the hydraulic system to be calibrated according to the relative current difference value and the standard current difference value comprises: calculating a difference value between the relative current difference value and the standard current difference value to obtain an absolute current difference value; and calibrating the control curve of the hydraulic system to be calibrated according to the absolute current difference value.

[0007] In an embodiment, after the relative current difference between the target current values of the adjacent target proportional valves is calculated, the automatic calibration method of the hydraulic system further comprises: calculating a slope of the hydraulic system to be calibrated according to the relative pressure difference and the relative current difference; wherein the slope of the hydraulic system to be calibrated represents the ratio of the relative pressure difference and the relative current difference; and determining the operating state of the hydraulic system to be calibrated according to the slope of the hydraulic system to be calibrated.

[0008] In an embodiment, the calculation of the slope of the hydraulic system to be calibrated according to the relative pressure difference and the relative current difference comprises: calculating a relative slope of the hydraulic system to be calibrated according to the relative pressure difference and the relative current difference; and calculating an absolute slope difference of the hydraulic system to be calibrated according to the relative slope and a standard slope; and the determination of the operating state of the hydraulic system to be calibrated according to the slope of the hydraulic system to be calibrated comprises: determining the operating state of the hydraulic system to be calibrated according to the absolute slope difference.

[0009] In an embodiment, the determination of the operating state of the hydraulic system to be calibrated according to the absolute slope difference comprises: when the absolute slope difference exceeds a preset slope range, predicting that the hydraulic system to be calibrated is operating abnormally and issuing a pre-warning signal.

[0010] In an embodiment, the determination of the operating state of the hydraulic system to be calibrated according to the absolute slope difference comprises: calculating a difference between the absolute slope difference of the current calibration and the absolute slope difference of the last calibration to obtain an absolute slope difference variation; and when the absolute slope difference variation exceeds a preset variation range, predicting that the hydraulic system to be calibrated is operating abnormally and issuing a pre-warning signal.

[0011] In an embodiment, after the target proportional valve of the hydraulic system to be calibrated is controlled and the target current value and the corresponding pump pressure value of the target proportional valve are obtained at each control point of the control curve, the automatic calibration method of the hydraulic system further comprises: adjusting the target current value when the target current value exceeds a preset current range; and determining that the hydraulic system to be calibrated is faulty if the relative pressure difference still does not satisfy the series standard after the target current value is adjusted.

[0012] In an embodiment, after the determination that the hydraulic system to be calibrated is faulty, the automatic calibration method of the hydraulic system further comprises: controlling the current change of the target proportional valve according to a preset wave function and collecting the corresponding pump pressure value; and determining that the repair is completed when the relative pressure difference between the adjacent pump pressure values satisfies the series standard.

[0013] According to another aspect of the present application, there is provided an automatic calibration device for a hydraulic system, comprising: a data acquisition module configured to control a target proportional valve of a hydraulic system to be calibrated to open based on each control point of a control curve, and acquire a target current value of the target proportional valve and a corresponding main pump pressure value; a pressure difference calculation module configured to calculate a relative pressure difference value between adjacent main pump pressure values; a current difference calculation module configured to calculate a relative current difference value between adjacent target current values when the relative pressure difference value meets a series of criteria; wherein the series of criteria is based on a standard pressure difference value; and a curve calibration module configured to calibrate the control curve of the hydraulic system to be calibrated according to the relative current difference value and a standard current difference value.

[0014] According to another aspect of the present application, there is provided an engineering machine comprising: a hydraulic system; and an automatic calibration device for a hydraulic system as described above.

[0015] The automatic calibration method, device and engineering machine for a hydraulic system provided by the present application, by controlling a target proportional valve of a hydraulic system to be calibrated to open based on each control point of a control curve, and acquiring a target current value of the target proportional valve and a corresponding main pump pressure value; calculating a relative pressure difference value between adjacent main pump pressure values; calculating a relative current difference value between adjacent target current values when the relative pressure difference value meets a series of criteria; and calibrating the control curve of the hydraulic system to be calibrated according to the relative current difference value and a standard current difference value; that is, in the calibration process, by calculating the relative pressure difference value between adjacent main pump pressure values corresponding to discrete points of the control curve, under the premise that the relative pressure difference value meets a series of criteria determined by the standard pressure difference value, calculating the relative current difference value between adjacent target current values, analyzing the relative current difference value and the standard current difference value to calibrate the control curve of the hydraulic system, to achieve the output effect of the engineering machine close to the expected standard, thereby improving the consistency and reliability of the engineering machine. BRIEF DESCRIPTION OF DRAWINGS

[0016] The above and other objects, features and advantages of the present application will become more apparent from the following detailed description thereof taken in conjunction with the accompanying drawings, in which like reference characters designate like elements in the several views. The accompanying drawings are intended to provide a further understanding of the embodiments of the present application and are incorporated in and constitute a part of this specification, illustrate embodiments of the present application and serve to explain the present application, and are not intended to limit the present application. In the drawings, like reference numerals refer to the same or similar elements throughout.

[0017] Figure 1 is a system diagram to which the present application is applicable.

[0018] Figure 2 is a flowchart of an automatic calibration method for a hydraulic system provided by an exemplary embodiment of the present application.

[0019] Figure 3 is a flowchart of an automatic calibration method of a hydraulic system according to another example embodiment of the present application.

[0020] Figure 4 is a flowchart of an automatic calibration method of a hydraulic system according to another example embodiment of the present application.

[0021] Figure 5 is a flowchart of a method for determining the operating state of a hydraulic system to be calibrated according to an example embodiment of the present application.

[0022] Figure 6 is a flowchart of an automatic calibration method of a hydraulic system according to another example embodiment of the present application.

[0023] Figure 7 is a flowchart of an automatic calibration method of a hydraulic system according to another example embodiment of the present application.

[0024] Figure 8 is a flowchart of an automatic calibration method of a hydraulic system according to another example embodiment of the present application.

[0025] Figure 9 is a flowchart of an automatic calibration method of a hydraulic system according to another example embodiment of the present application.

[0026] Figure 10 is a structural diagram of an automatic calibration device of a hydraulic system according to an example embodiment of the present application.

[0027] Figure 11 is a structural diagram of an automatic calibration device of a hydraulic system according to another example embodiment of the present application.

[0028] Figure 12 is a structural diagram of an electronic device according to an example embodiment of the present application. DETAILED DESCRIPTION

[0029] Hereinafter, example embodiments according to the present application will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only a part but not all of the embodiments of the present application. It should be understood that the present application is not limited to the described embodiments, but rather the scope of the present application is limited only by the appended claims.

[0030] With the continuous development of electric control technology and intelligent technology, electric, intelligent and digital construction machinery is also developing rapidly. For example, the control mode of the main valve of most machines such as excavators and loaders is changed from hydraulic control to electric control. The electric signal of the handle is converted into the pressure of the pilot oil port, and further converted into the opening area (opening degree) of the valve core, so as to realize the control of the flow and pressure. Through the cooperation of multiple valves, the distribution and control of the flow are realized, and the expected action is completed. At the same time, the automation and intelligence development of construction machinery also provides conditions and foundation for its automatic calibration.

[0031] The structure of the hydraulic system to which the present application is applied will be described below with reference to an excavator as an example and in conjunction with the drawings. It should be understood that the present application is described only by taking the excavator as an example, and is not limited to the construction machinery containing only the excavator. The construction machinery described in the present application is the construction machinery containing the hydraulic system.

[0032] Figure 1 is a system diagram to which the present application is applied. As shown in Figure 1 , the hydraulic system of the excavator comprises an oil tank 1, a pilot pump 2, a main pump 3, an unloading valve 4, a bucket valve 5, a bucket cylinder 6 and a controller 7. The unloading valve 4 and the bucket valve 5 can be electromagnetic proportional valves or other valves. The operator inputs a control signal through a handle, which is converted into a pilot oil pressure signal and transmitted to the pilot pump. The pilot pump provides a pilot pressure to control the output flow and pressure of the main pump. The present application outputs a current signal to the bucket valve 5, the main pump proportional valve (not shown in the figure) and the unloading valve 4 through the controller 7, so as to control the current of the main pump proportional valve and the unloading valve 4 at a certain set value, and change the current of the bucket valve 5. At the same time, the main pump pressure value P of the main pump 3 and the current value I of the bucket valve 5 are collected by the sensor. The current of the bucket valve 5 is changed continuously for multiple times, and the corresponding main pump pressure value and the current value of the bucket valve 5 are collected, so as to obtain multiple discrete points of the control curve. The multiple discrete points are calibrated to obtain the calibrated control curve.

[0033] Figure 2 is a flow diagram of an automatic calibration method of a hydraulic system provided by an exemplary embodiment of the present application. The automatic calibration method of the hydraulic system is applied to the controller of the above-mentioned hydraulic system. As shown in Figure 2 , the automatic calibration method of the hydraulic system comprises the following steps:

[0034] Step 210: based on each control point of the control curve, the target proportional valve of the hydraulic system to be calibrated is controlled to be opened, and the target current value of the target proportional valve and the corresponding main pump pressure value are obtained.

[0035] The control curve can be obtained based on the engineering machinery corresponding to the hydraulic system to be calibrated. Specifically, by changing the current of the target proportional valve (such as the bucket valve mentioned above) and collecting the corresponding main pump pressure value and target current value, multiple discrete control points are obtained (specifically, the pilot valve pressure value and the target proportional valve current value). A control curve is then fitted based on these discrete control points. This application controls the current of the hydraulic system to be calibrated according to each control point of the control curve to achieve the target current value and the corresponding main pump pressure value for the target proportional valve and the main pump, respectively. Specifically, the current of the target proportional valve can be changed according to actual operational requirements.

[0036] Step 220: Calculate the relative pressure difference between adjacent main pump pressure values.

[0037] By calculating the relative pressure difference between adjacent main pump pressure values, the change in main pump pressure corresponding to adjacent target current values ​​can be determined. Specifically, the relative pressure difference ΔP between the i-th discrete point and the (i-1)-th discrete point of the hydraulic system to be calibrated is calculated. i =P i -P i-1 , where P i Let P be the main pump pressure value corresponding to the i-th discrete point of the hydraulic system to be calibrated. i-1 Let P be the main pump pressure value corresponding to the (i-1)th discrete point of the hydraulic system to be calibrated, 0 ≤ i ≤ n, where n is the number of discrete control points in the control curve, 0 ≤ P. i ≤P max P max This is the maximum pressure of the main pump.

[0038] Step 230: When the relative pressure difference meets the series of standards, calculate the relative current difference between adjacent target current values.

[0039] Among them, the series of standards are based on the standard pressure difference value, the standard pressure difference ΔP 0i ΔP is the difference in main pump pressure between the i-th discrete point and the (i-1)-th discrete point in the control curve of the standard prototype equipment. 0i =P 0i -P 0(i-1) , where P 0i Let P be the main pump pressure value corresponding to the i-th discrete point of the standard prototype equipment. 0(i-1) This refers to the main pump pressure value corresponding to the (i-1)th discrete point of the standard prototype equipment. Specifically, the relative pressure difference of the hydraulic system to be calibrated must meet a series of standards, meaning all relative pressure differences of the hydraulic system to be calibrated are the same as the standard pressure difference, or their differences are less than a preset value. The relative current difference between adjacent target current values ​​(i.e., at different set pressure differences)

[0040] ΔP irelative current value of the i-th discrete point of the standard sample device i = I i - I i-1 , wherein I i is the target current value of the i-th discrete point of the hydraulic system to be calibrated, I i-1 is the target current value of the i-1-th discrete point of the hydraulic system to be calibrated, 0≤I i ≤I max , I max is the maximum current value of the target proportional valve. It should be understood that one or more key discrete points can be selected according to actual needs to calculate the corresponding relative current difference value, and the control curve is calibrated according to the calculated relative current difference value. Preferably, the application can select continuous discrete points to calculate the corresponding relative current difference value, and calibrate the control curve according to the calculated relative current difference value, so as to improve the control accuracy of the control curve as much as possible.

[0041] Step 240: calibrating the control curve of the hydraulic system to be calibrated according to the relative current difference value and the standard current difference value.

[0042] After calculating the relative current difference value of the hydraulic system to be calibrated and the standard current difference value of the standard sample device, the control curve of the hydraulic system to be calibrated is calibrated based on the standard current difference value of the standard sample device, so as to exclude the interference of environmental factors (such as temperature, pressure, etc.) on the calibration, so as to improve the accuracy and consistency of the calibration. Wherein, the standard current difference value ΔI 0i = I 0i - I 0(i-1) , wherein I 0i is the current value of the target proportional valve corresponding to the i-th discrete point of the standard sample device, I 0(i-1) is the current value of the target proportional valve corresponding to the i-1-th discrete point of the standard sample device.

[0043] In an embodiment, the specific implementation of step 240 can be: calculating the difference between the relative current difference value and the standard current difference value to obtain the absolute current difference value, and calibrating the control curve of the hydraulic system to be calibrated according to the absolute current difference value. Wherein, the absolute current difference value ΔI S(i-1) = ΔI (i-1) - ΔI 0(i-1) of the i-1-th discrete point, the absolute current difference value ΔI Si = I i - I 0i - (ΔI S(i-1) + ΔI S(i-2) + … + ΔI S1 ).

[0044] The application provides an automatic calibration method of a hydraulic system. The method comprises the following steps: based on each control point of a control curve, controlling a target proportional valve of a hydraulic system to be calibrated to open and obtaining a target current value of the target proportional valve and a corresponding main pump pressure value; calculating a relative pressure difference value between adjacent main pump pressure values; when the relative pressure difference value meets a series of standards, calculating a relative current difference value between adjacent target current values; and calibrating the control curve of the hydraulic system to be calibrated according to the relative current difference value and a standard current difference value. In the calibration process, the relative pressure difference value between adjacent main pump pressure values corresponding to discrete points of the control curve is calculated, the relative current difference value between adjacent target current values is calculated on the premise that the relative pressure difference value meets a series of standards determined by the standard pressure difference value, the control curve of the hydraulic system is calibrated by analyzing the relative current difference value and the standard current difference value, so that the output effect of the engineering machinery approaches the expected standard, and the consistency and reliability of the engineering machinery are improved.

[0045] Figure 3 is a flowchart of an automatic calibration method of a hydraulic system according to another example embodiment of the application. As shown in Figure 3 the automatic calibration method of the hydraulic system can further comprise the following steps after step 230:

[0046] Step 250: calculating a slope of the hydraulic system to be calibrated according to the relative pressure difference value and the relative current difference value.

[0047] The slope of the hydraulic system to be calibrated represents the proportion of the relative pressure difference value and the relative current difference value.

[0048] Step 260: determining the running state of the hydraulic system to be calibrated according to the slope of the hydraulic system to be calibrated.

[0049] The application can predict the running state or future trend of the hydraulic system to be calibrated by calculating the slope of the hydraulic system to be calibrated to predict the change trend of the relative pressure difference value and the relative current difference value of the hydraulic system to be calibrated.

[0050] Figure 4 is a flowchart of an automatic calibration method of a hydraulic system according to another example embodiment of the application. As shown in Figure 4 the step 250 can comprise the following steps:

[0051] Step 251: calculating a relative slope of the hydraulic system to be calibrated according to the relative pressure difference value and the relative current difference value.

[0052] Specifically, the relative slope of the hydraulic system to be calibrated is ΔK i = ΔP i / ΔI i .

[0053] Step 252: according to the relative slope and the standard slope, the absolute slope difference of the hydraulic system to be calibrated is calculated.

[0054] Specifically, the standard slope ΔK 0i = ΔP 0i / ΔI 0i , and the absolute slope difference ΔK Si of the hydraulic system to be calibrated = ΔK i - ΔK 0i .

[0055] Correspondingly, step 260 can include:

[0056] Step 261: according to the absolute slope difference, the running state of the hydraulic system to be calibrated is determined.

[0057] By comparing the relative slope of the hydraulic system to be calibrated and the standard slope of the standard prototype device, the running state of the hydraulic system to be calibrated is determined, so that the change trend of the relative pressure difference and the relative current difference of the hydraulic system to be calibrated can be predicted to determine whether the hydraulic system to be calibrated has a fault or a hidden danger.

[0058] In an embodiment, the specific implementation of step 261 can be: when the absolute slope difference exceeds the preset slope range, it is predicted that the hydraulic system to be calibrated is running abnormally and a pre-alarm signal is sent.

[0059] For example, if the difference between the relative slope of the hydraulic system to be calibrated and the standard slope of the standard prototype device is large, it indicates that the running state of the hydraulic system to be calibrated has a fault or a hidden danger.

[0060] In an embodiment, the specific implementation of step 261 can be: the difference between the absolute slope difference of this calibration and the absolute slope difference of the last calibration is calculated to obtain the absolute slope difference variation, and when the absolute slope difference variation exceeds the preset variation range, it is predicted that the hydraulic system to be calibrated is running abnormally and a pre-alarm signal is sent. The present application obtains the absolute slope difference variation by calculating the difference between the absolute slope difference of this calibration and the absolute slope difference of the last calibration, so as to obtain the change trend of the absolute slope difference of the hydraulic system to be calibrated, and when the absolute slope difference variation exceeds the preset variation range, it indicates that the change trend of the absolute slope difference is changing in an abnormal direction, at which time it can be predicted that the hydraulic system to be calibrated is running abnormally and a pre-alarm signal is sent. Specifically, as shown in Figure 5 the running state determination method includes the following steps:

[0061] Step 510: calculate the absolute slope difference variation of this calibration.

[0062] Specifically, the absolute slope difference variation amount ΔK of the i-th node of the hydraulic system to be calibrated in the N-th overall calibration (this calibration) is calculated as follows: TSi

[0063] ΔK TSi = ΔK NSi - ΔK (N-1)Si = ΔK Ni - ΔK (N-1)i ;

[0064] wherein ΔK NSi is the absolute slope difference of this calibration, ΔK （N-1)Si is the absolute slope difference of the last calibration, ΔK Ni is the relative slope of this calibration, ΔK (N-1)i is the relative slope of the last calibration, N≥2, 0≤i≤n.

[0065] Step 520: determining whether the absolute slope difference variation amount of this calibration is within the preset variation range, if yes, turning to step 530, otherwise, turning to step 540.

[0066] Step 530: determining that the running state is normal.

[0067] If the absolute slope difference variation rate of this calibration is within the preset variation range (error range), it indicates that the relative slope of the hydraulic system to be calibrated changes less, and the performance of the corresponding hydraulic system to be calibrated is more stable, and thus it can be determined that the hydraulic system to be calibrated tends to be in a normal state.

[0068] Step 540: determining that the running state is abnormal, and the system fault is predicted and warned.

[0069] If the absolute slope difference variation rate of this calibration exceeds the preset variation range (error range), it indicates that the relative slope of the hydraulic system to be calibrated changes more, and the performance of the corresponding hydraulic system to be calibrated is unstable, and thus it can be determined that the hydraulic system to be calibrated tends to be in an abnormal state.

[0070] Figure 6 is a flowchart of an automatic calibration method of a hydraulic system provided by another exemplary embodiment of the present application. As shown in Figure 6 , after step 210, the automatic calibration method of the hydraulic system can further include:

[0071] Step 270: adjusting the target current value when the target current value exceeds the preset current range.

[0072] ​When the target current value exceeds the preset current range, it indicates that the hydraulic system to be calibrated is abnormal. However, the abnormality of the hydraulic system may be caused by excessive error (which cannot be reduced or eliminated) or system failure (which can be reduced and eliminated). At this time, in order to further determine the cause of the abnormality, the present application starts the abnormality cause determination process after the first abnormality alarm, and adjusts the target current. Specifically, the target current value can be modified by setting a function.

[0073] Step 280: If the relative pressure difference value still does not meet the series standard after adjusting the target current value, it is determined that the hydraulic system to be calibrated is faulty.

[0074] If the relative pressure difference value of the corresponding main pump pressure value still does not meet the series standard after adjusting the target current value, it indicates that the hydraulic system to be calibrated has a problem, i.e., it can be determined that the cause of the abnormality of the hydraulic system to be calibrated is system failure, and an alarm prompt of system failure can be issued. If the relative pressure difference value of the corresponding main pump pressure value meets the series standard after adjusting the target current value, it indicates that the hydraulic system to be calibrated does not have a problem, i.e., it can be determined that the cause of the abnormality of the hydraulic system to be calibrated is excessive error, and an alarm prompt of excessive error can be issued.

[0075] Figure 7 is a flowchart of an automatic calibration method of a hydraulic system provided by another exemplary embodiment of the present application. As shown in Figure 7 After step 280, the automatic calibration method of the hydraulic system described above can further include:

[0076] Step 290: Overhauling the hydraulic system to be calibrated.

[0077] In an embodiment, the specific implementation of step 290 can be: controlling the current change of the target proportional valve according to a preset wave function, and collecting the corresponding main pump pressure value, and when the relative pressure difference value between the corresponding main pump pressure values meets the series standard, it is determined that the repair is complete. When the hydraulic system failure alarm signal is detected, the overhauling process can be started after the completion of the present calibration, the target current is changed in the form of a wave function, the relative pressure difference value between the main pump pressure values of adjacent two discrete points is calculated, and it is determined whether each relative pressure difference value meets the requirement. If yes, it is prompted that the repair is complete, and the calibration can be continued. If not, it is prompted that the overhauling is not completed. Specifically, as shown in Figure 8 The overhauling method includes the following steps:

[0078] Step 810: It is determined whether there is an overhauling signal. If yes, go to step 820, otherwise go to step 830.

[0079] Specifically, the overhauling signal can be a hydraulic system failure alarm signal, or a manually input overhauling signal.

[0080] Step 820: change the current of the target proportional valve according to the set wave function.

[0081] That is, change the current of the target proportional valve (target current) according to the set wave function and synchronously collect the main pump pressure value corresponding to the main pump, and then obtain the relative pressure difference value between the main pump pressure values of adjacent discrete points.

[0082] Step 830: prompt that no repair is needed.

[0083] Step 840: determine whether the relative pressure difference value meets the requirement, if yes, go to step 850, otherwise go to step 860.

[0084] Specifically, determine whether the relative pressure difference value between the main pump pressure values of adjacent two discrete points meets the series requirement (for example, the requirement of the series standard).

[0085] Step 850: prompt that the repair is completed.

[0086] Step 860: prompt that the repair fails.

[0087] Figure 9 is a flowchart of an automatic calibration method of a hydraulic system provided by another exemplary embodiment of the present application. As shown in the figure, the automatic calibration method of the hydraulic system can include the following steps: Figure 9

[0088] Step 901: collect the target current value and the main pump pressure value.

[0089] Specifically, set a separate oil circuit for the prototype device, and control the target current of the target proportional valve and the current of other auxiliary valves, and synchronously collect the main pump pressure value of the main pump.

[0090] Step 902: determine whether the target current value is out of range, if yes, go to step 903, otherwise go to step 904.

[0091] Step 903: system abnormality alarm.

[0092] This step is similar to the above-mentioned step 270, which will not be described here again.

[0093] Step 904: determine whether the relative pressure difference value between adjacent main pump pressure values reaches the series standard, if yes, go to step 905, otherwise go to step 901.

[0094] This step is similar to the above-mentioned step 280, which will not be described here again.

[0095] Step 905: calculate the absolute slope difference value.

[0096] This step is similar to the above-mentioned step 250, which will not be described here again.​

[0097] Step 906: Determine whether the absolute slope difference exceeds the preset slope range. If yes, proceed to step 907; otherwise, proceed to step 908.

[0098] Step 907: System pre-alarm.

[0099] This step is similar to step 260 above, and will not be repeated here.

[0100] Step 908: Increment the calibration count by 1.

[0101] Step 909: Determine whether the number of calibrations exceeds the preset number. If yes, proceed to step 910; otherwise, proceed to step 901.

[0102] Step 910: Calibrate the control curve point by point.

[0103] Figure 10 This is a schematic diagram of the structure of an automatic calibration device for a hydraulic system provided in an exemplary embodiment of this application. Figure 10 As shown, the automatic calibration device 90 of the hydraulic system includes: a data acquisition module 91, used to control the target proportional valve of the hydraulic system to be calibrated to open and acquire the target current value and the corresponding main pump pressure value of the target proportional valve based on each control point of the control curve; a pressure difference calculation module 92, used to calculate the relative pressure difference between adjacent main pump pressure values; a current difference calculation module 93, used to calculate the relative current difference between adjacent target current values ​​when the relative pressure difference meets a series of standards; wherein the series of standards are obtained based on the standard pressure difference; and a curve calibration module 94, used to calibrate the control curve of the hydraulic system to be calibrated according to the relative current difference and the standard current difference.

[0104] This application provides an automatic calibration device for a hydraulic system. A data acquisition module 91, based on each control point of the control curve, controls the opening of the target proportional valve of the hydraulic system to be calibrated and acquires the target current value of the target proportional valve and the corresponding main pump pressure value. A pressure difference calculation module 92 calculates the relative pressure difference between adjacent main pump pressure values. When the relative pressure difference meets a series of standards, a current difference calculation module 93 calculates the relative current difference between adjacent target current values. A curve calibration module 94 calibrates the control curve of the hydraulic system to be calibrated based on the relative current difference and the standard current difference. In other words, during the calibration process, by calculating the relative pressure difference between adjacent main pump pressure values ​​corresponding to discrete points of the control curve, and under the premise that the relative pressure difference meets a series of standards determined by the standard pressure difference, the relative current difference between adjacent target current values ​​is calculated. The relative current difference and the standard current difference are analyzed to calibrate the control curve of the hydraulic system, so as to achieve an output effect of the engineering machinery that is close to the expected standard, thereby improving the consistency and reliability of the engineering machinery.

[0105] In an embodiment, the curve calibration module 94 can be further configured to: calculate a difference between the relative current difference value and the standard current difference value to obtain an absolute current difference value, and calibrate the control curve of the hydraulic system to be calibrated according to the absolute current difference value.

[0106] Figure 11 is a structural schematic diagram of an automatic calibration device of a hydraulic system according to another exemplary embodiment of the present application. As shown in Figure 11 The automatic calibration device 90 of the hydraulic system can further include: a slope calculation module 95 configured to calculate a slope of the hydraulic system to be calibrated according to the relative pressure difference value and the relative current difference value, wherein the slope of the hydraulic system to be calibrated represents a ratio of the relative pressure difference value and the relative current difference value; and a state determination module 96 configured to determine an operating state of the hydraulic system to be calibrated according to the slope of the hydraulic system to be calibrated.

[0107] In an embodiment, as shown in Figure 11 The slope calculation module 95 can include: a first calculation unit 951 configured to calculate a relative slope of the hydraulic system to be calibrated according to the relative pressure difference value and the relative current difference value; and a second calculation unit 952 configured to calculate an absolute slope difference value of the hydraulic system to be calibrated according to the relative slope and a standard slope. Correspondingly, the state determination module 96 can be further configured to determine the operating state of the hydraulic system to be calibrated according to the absolute slope difference value.

[0108] In an embodiment, the state determination module 96 can be further configured to predict that the hydraulic system to be calibrated is operating abnormally and issue a pre-alarm signal when the absolute slope difference value exceeds a preset slope range.

[0109] In an embodiment, the state determination module 96 can be further configured to calculate a difference between the absolute slope difference value of the present calibration and the absolute slope difference value of the last calibration to obtain an absolute slope difference variation, and predict that the hydraulic system to be calibrated is operating abnormally and issue a pre-alarm signal when the absolute slope difference variation exceeds a preset variation range.

[0110] In an embodiment, as shown in Figure 11 The automatic calibration device 90 of the hydraulic system can further include: a current adjustment module 97 configured to adjust the target current value when the target current value exceeds a preset current range; and a fault determination module 98 configured to determine that the hydraulic system to be calibrated is faulty if the relative pressure difference value between the adjacent main pump pressure values still does not satisfy the series standard after the target current value is adjusted.

[0111] In an embodiment, as shown in Figure 11As shown, the automatic calibration device 90 of the hydraulic system can further include a system maintenance module 99 configured to perform maintenance on the hydraulic system to be calibrated.

[0112] In an embodiment, the system maintenance module 99 can be further configured to control the current of the target proportional valve according to the preset wave function, collect the corresponding main pump pressure values, and determine that the maintenance is completed when the relative pressure difference between the corresponding main pump pressure values meets the series of standards.

[0113] The application also provides an engineering machine, comprising: a hydraulic system; and an automatic calibration device of the hydraulic system as above.

[0114] The application provides an engineering machine, which controls the opening of a target proportional valve of a hydraulic system to be calibrated based on each control point of a control curve, acquires a target current value of the target proportional valve and a corresponding main pump pressure value, calculates a relative pressure difference between adjacent main pump pressure values, calculates a relative current difference between adjacent target current values when the relative pressure difference meets a series of standards, and calibrates the control curve of the hydraulic system to be calibrated according to the relative current difference and a standard current difference; that is, in the calibration process, the relative pressure difference between adjacent main pump pressure values corresponding to discrete points of the control curve is calculated, the relative current difference between adjacent target current values is calculated on the premise that the relative pressure difference meets a series of standards determined by the standard pressure difference, the control curve of the hydraulic system is calibrated by analyzing the relative current difference and the standard current difference, so that the output effect of the engineering machine approaches the expected standard, thereby improving the consistency and reliability of the engineering machine.

[0115] Next, an electronic device according to embodiments of the application will be described with reference to Figure 12 The electronic device can be either or both of the first and second devices, or a standalone device independent of them, which can communicate with the first and second devices to receive the acquired input signals therefrom.

[0116] Figure 12 FIG. 1 illustrates a block diagram of an electronic device according to embodiments of the application.

[0117] As Figure 12 shown, the electronic device 10 includes one or more processors 11 and a memory 12.

[0118] The processor 11 can be a central processing unit (CPU) or other form of processing unit having data processing and / or instruction execution capabilities, and can control other components in the electronic device 10 to perform desired functions.

[0119] The memory 12 can include one or more computer program products that can include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory, for example, can include random access memory (RAM), cache memory, and / or the like. The non-volatile memory, for example, can include read only memory (ROM), hard disk, flash memory, and / or the like. One or more computer program instructions can be stored on the computer-readable storage media, which the processor 11 can execute to implement the methods of the embodiments of the present application described above and / or other desired functions. Various contents such as input signals, signal components, noise components, and the like can also be stored in the computer-readable storage media.

[0120] In one example, the electronic device 10 can further include an input device 13 and an output device 14, which are interconnected through a bus system and / or other forms of connection mechanisms (not shown).

[0121] When the electronic device is a stand-alone device, the input device 13 can be a communication network connector for receiving acquired input signals from the first device and the second device.

[0122] In addition, the input device 13 can further include, for example, a keyboard, a mouse, and the like.

[0123] The output device 14 can output various information including the determined distance information, direction information, and the like to the outside. The output device 14 can include, for example, a display, a speaker, a printer, a communication network and a remote output device connected thereto, and the like.

[0124] Of course, in order to simplify, Figure 12 Only some of the components of the electronic device 10 related to the present application are shown in the block diagram of FIG. 1, and components such as a bus, an input / output interface, and the like are omitted. In addition to this, the electronic device 10 can further include any other appropriate components according to the specific application.

[0125] The computer program product can be written in any combination of one or more programming languages, including an object oriented programming language such as Java, C++, and the like, and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The program code can execute entirely on the user's computing device, partly on the user's device, as a stand-alone software package, partly on the user's computing device and partly on a remote computing device or entirely on the remote cloud device or server.

[0126] The computer readable storage medium can be any combination of one or more computer readable media. The computer readable medium can be a computer readable signal medium or a computer readable storage medium. A computer readable storage medium can be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the computer readable storage medium include an electrical connection having one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0127] The foregoing description has been presented for the purposes of illustration and description. Furthermore, the description is not intended to limit the embodiments of the application to the form disclosed herein. Although various example aspects and embodiments have been discussed above, those of ordinary skill in the art will appreciate a variety of modifications, alternatives, permutations, additions, and sub-combinations of the described aspects and embodiments.

Claims

1. A method of automatic calibration of a hydraulic system, characterized in that, The method comprises: controlling a target proportional valve of a hydraulic system to be calibrated to open based on each control point of a control curve, and obtaining a target current value of the target proportional valve and a corresponding main pump pressure value; calculating a relative pressure difference between adjacent main pump pressure values; when the relative pressure difference meets a series of criteria, calculating a relative current difference between adjacent target current values; wherein the series of criteria is based on a standard pressure difference value, and the relative pressure difference meeting the series of criteria includes the relative pressure difference being the same as the standard pressure difference value or having a difference less than a preset value; and calibrating the control curve of the hydraulic system to be calibrated according to the relative current difference and a standard current difference.

2. The method of automatic calibration of a hydraulic system according to claim 1, wherein, The calibration of the control curve of the hydraulic system to be calibrated according to the relative current difference and the standard current difference comprises: calculating a difference between the relative current difference and the standard current difference to obtain an absolute current difference; and calibrating the control curve of the hydraulic system to be calibrated according to the absolute current difference.

3. The method of automatic calibration of a hydraulic system of claim 1, wherein, After the calculation of the relative current difference between adjacent target current values, the automatic calibration method of the hydraulic system further comprises: calculating a slope of the hydraulic system to be calibrated according to the relative pressure difference and the relative current difference; wherein the slope of the hydraulic system to be calibrated represents the proportion of the relative pressure difference and the relative current difference; and determining an operating state of the hydraulic system to be calibrated according to the slope of the hydraulic system to be calibrated.

4. The method of automatic calibration of a hydraulic system of claim 3, wherein, The calculation of the slope of the hydraulic system to be calibrated according to the relative pressure difference and the relative current difference comprises: calculating a relative slope of the hydraulic system to be calibrated according to the relative pressure difference and the relative current difference; and calculating an absolute slope difference of the hydraulic system to be calibrated according to the relative slope and a standard slope; The determination of the operating state of the hydraulic system to be calibrated according to the slope of the hydraulic system to be calibrated comprises: determining the operating state of the hydraulic system to be calibrated according to the absolute slope difference.

5. The method of automatic calibration of a hydraulic system of claim 4, wherein, The determination of the operating state of the hydraulic system to be calibrated according to the absolute slope difference comprises: when the absolute slope difference exceeds a preset slope range, predicting that the hydraulic system to be calibrated is operating abnormally and issuing a pre-warning signal.

6. The method of automatic calibration of a hydraulic system of claim 4, wherein, The determination of the operating state of the hydraulic system to be calibrated according to the absolute slope difference comprises: calculating a difference between the absolute slope difference of this calibration and the absolute slope difference of the last calibration to obtain an absolute slope difference change amount; and when the absolute slope difference change amount exceeds a preset change range, predicting that the hydraulic system to be calibrated is operating abnormally and issuing a pre-warning signal.

7. The method of automatic calibration of a hydraulic system of claim 1, wherein, After the control of the target proportional valve of the hydraulic system to be calibrated to open based on each control point of the control curve, and the obtaining of the target current value of the target proportional valve and the corresponding main pump pressure value, the automatic calibration method of the hydraulic system further comprises: when the target current value exceeds a preset current range, adjusting the target current value; If the relative pressure difference value still does not satisfy the series of standards after adjusting the target current value, it is determined that the hydraulic system to be calibrated is faulty.

8. The method of automatic calibration of a hydraulic system of claim 7, wherein, After the determination that the hydraulic system to be calibrated is faulty, the automatic calibration method of the hydraulic system further comprises: controlling the current change of the target proportional valve according to a preset wave function, and collecting corresponding main pump pressure values; When the relative pressure difference value between adjacent main pump pressure values satisfies the series of standards, it is determined that the repair is completed.

9. An apparatus for automatic calibration of a hydraulic system, characterized by The method comprises: a data acquisition module configured to control a target proportional valve of a hydraulic system to be calibrated to open based on each control point of a control curve, and acquire a target current value of the target proportional valve and corresponding main pump pressure values; a pressure difference calculation module configured to calculate a relative pressure difference value between adjacent main pump pressure values; a current difference calculation module configured to calculate a relative current difference value between adjacent target current values when the relative pressure difference value satisfies a series of standards, wherein the series of standards is obtained based on a standard pressure difference value, and the relative pressure difference value satisfying the series of standards includes the relative pressure difference value being the same as the standard pressure difference value or the difference being less than a preset value; and a curve calibration module configured to calibrate the control curve of the hydraulic system to be calibrated according to the relative current difference value and a standard current difference value. The method comprises:

10. A working machine, characterized in that a hydraulic system; and an automatic calibration device of the hydraulic system according to claim 9. ​

Images