阅读说明：本技术 串联电磁阀的电流检测方法及装置 (Current detection method and device for series electromagnetic valve ) 是由 于鹏飞 孙晓鹏 赵金光 许力杰 于 2020-12-23 设计创作，主要内容包括：本申请公开了一种串联电磁阀的电流检测方法及装置,其中,所述方法通过将目标设备的电流从零逐步增加,直至检测到液压马达的转速大于目标设备的起调转速,采集目标设备的实际电流,得到最小起调电流；以及将目标设备的电流设定为单个电磁阀的终调电流与第二预设值的和,采集到第三转速,以能通过逐步减小目标设备的电流,至小于第三转速时,采集到最大终调电流和第四转速,得到起始、终调单一电磁阀工作时电流曲线。通过采集两个串联电磁均已工作时的两组数据,得到两个串联电磁工作时的目标直线。单一电磁阀工作时电流曲线为目标曲线的斜率的一半,确定出起始、终调单一电磁阀工作时电流曲线与目标直线交点,得到较大起调电流和较小终点电流。(The application discloses a current detection method and a current detection device of a series electromagnetic valve, wherein the method comprises the steps of gradually increasing the current of target equipment from zero until the rotating speed of a hydraulic motor is detected to be larger than the starting adjusting rotating speed of the target equipment, and collecting the actual current of the target equipment to obtain the minimum starting adjusting current; and setting the current of the target equipment as the sum of the final regulation current of the single electromagnetic valve and a second preset value, and acquiring a third rotating speed so as to acquire a maximum final regulation current and a fourth rotating speed when the current of the target equipment is gradually reduced to be less than the third rotating speed, thereby obtaining a current curve when the single electromagnetic valve works in the initial regulation and the final regulation. The target straight line of the two series electromagnets in working is obtained by collecting two groups of data of the two series electromagnets in working. The current curve of the single electromagnetic valve during working is half of the slope of the target curve, the intersection point of the current curve of the single electromagnetic valve during working and the target straight line during initial and final adjustment is determined, and a larger starting adjustment current and a smaller end point current are obtained.)

1. A current detection method of a series electromagnetic valve is characterized by comprising the following steps:

gradually increasing the current of the target equipment from zero until the rotation speed of the hydraulic motor is detected to be greater than the starting rotation speed of the target equipment; wherein the target equipment is the hydraulic motor or a hydraulic pump in a hydraulic power system to which the hydraulic motor belongs;

acquiring the actual current of the target equipment to obtain the minimum starting current;

setting the current of the target equipment as a target current, and executing acquisition operation to obtain a first current and a first rotating speed; wherein the collecting operation is to collect an actual current of the target device and an actual rotational speed of the hydraulic motor; the two series electromagnetic valves corresponding to the target equipment are both started and adjusted under the target current;

setting the current of the target equipment as the difference value between the single final adjustment current of the electromagnet and a first preset value, and executing the acquisition operation to obtain a second current and a second rotating speed;

setting the current of the target equipment as the sum of the final regulation current of a single electromagnetic valve and a second preset value, and executing the acquisition operation to obtain a third current and a third rotating speed;

gradually reducing the current of the target device until the rotation speed of the hydraulic motor is detected to be less than the third rotation speed;

executing the acquisition operation to obtain a maximum final adjusting current and a fourth rotating speed;

determining a current value in an intersection point coordinate of a first straight line where a first coordinate is located and a target straight line as a first synchronous current, and determining a current value in an intersection point coordinate of a second straight line where a fourth coordinate is located and the target straight line as a first final current;

wherein the first coordinate comprises the minimum key-on current and a key-on speed of the target device; the fourth coordinate comprises the maximum final regulation current and the fourth rotation speed; the target straight line is a straight line where a second coordinate and a third coordinate are located together, and the second coordinate comprises the first current and the first rotating speed; the third coordinate comprises the second current and the second rotational speed; the slope of the target straight line is twice that of the first straight line, and the slopes of the first straight line and the second straight line are equal.

2. The method of claim 1, wherein setting the current of the target device to a target current comprises:

and setting the current of the target device as the sum of the minimum start-up current and a third preset value.

3. The method of claim 1, wherein setting the current of the target device to a target current and performing a capture operation to obtain a first current and a first speed comprises:

setting a current of the target device to a target current;

executing the acquisition operation for preset times to obtain multiple groups of first acquisition data;

calculating the mean value of all currents in the multiple groups of first collected data to obtain the first currents, and calculating the mean value of all rotating speeds in the multiple groups of first collected data to obtain the first rotating speed.

4. The method of claim 1, wherein the setting the current of the target device to a sum of a final regulated current of a single solenoid valve and a second preset value and performing the collecting operation to obtain a third current and a third rotational speed comprises:

setting the current of the target equipment as the sum of the final regulating current of the electromagnetic valve and a second preset value;

executing the acquisition operation for preset times to obtain multiple groups of second acquisition data;

and respectively calculating the mean value of all currents in the multiple groups of second collected data and the mean value of all rotating speeds in the multiple groups of second collected data to obtain a third current and a third rotating speed.

5. The method of claim 1, wherein the step-wise decreasing the current of the target device until the rotational speed of the hydraulic motor is detected to be less than the third rotational speed further comprises:

setting the current of the target device to the third current.

6. A current detection device of a series solenoid valve, comprising:

a first adjusting unit for gradually increasing the current of a target device from zero until detecting that the rotation speed of a hydraulic motor is greater than the starting adjustment rotation speed of the target device; wherein the target equipment is the hydraulic motor or a hydraulic pump in a hydraulic power system to which the hydraulic motor belongs;

the first acquisition unit is used for acquiring the actual current of the target equipment to obtain the minimum starting current;

the second acquisition unit is used for setting the current of the target equipment as a target current and executing acquisition operation to obtain a first current and a first rotating speed; wherein the collecting operation is to collect an actual current of the target device and an actual rotational speed of the hydraulic motor; the two series electromagnetic valves corresponding to the target equipment are both started and adjusted under the target current;

the third acquisition unit is used for setting the current of the target equipment as the difference value between the single final modulation current of the electromagnet and a first preset value, and executing the acquisition operation to obtain a second current and a second rotating speed;

the fourth acquisition unit is used for setting the current of the target equipment as the sum of the final regulation current of the single electromagnetic valve and a second preset value, and executing the acquisition operation to obtain a third current and a third rotating speed;

a second adjustment unit for gradually reducing the current of the target device until it is detected that the rotation speed of the hydraulic motor is less than the third rotation speed;

the fifth acquisition unit is used for executing the acquisition operation to obtain the maximum final adjustment current and the fourth rotating speed;

the determining unit is used for determining a current value in an intersection point coordinate of a first straight line where the first coordinate is located and the target straight line as a first synchronous regulation current, and determining a current value in an intersection point coordinate of a second straight line where the fourth coordinate is located and the target straight line as a first final regulation current;

wherein the first coordinate comprises the minimum key-on current and a key-on speed of the target device; the fourth coordinate comprises the maximum final regulation current and the fourth rotation speed; the target straight line is a straight line where a second coordinate and a third coordinate are located together, and the second coordinate comprises the first current and the first rotating speed; the third coordinate comprises the second current and the second rotational speed; the slope of the target straight line is twice that of the first straight line, and the slopes of the first straight line and the second straight line are equal.

7. The apparatus of claim 6, wherein the second acquisition unit, when executing the setting of the current of the target device to the target current, is configured to:

and setting the current of the target device as the sum of the minimum start-up current and a third preset value.

8. The apparatus of claim 6, wherein the second acquisition unit comprises:

a first setting unit for setting a current of the target device as a target current;

the second acquisition subunit is used for executing the acquisition operation for preset times to obtain multiple groups of first acquisition data;

the first calculating unit is used for calculating the mean value of all currents in the multiple groups of first collected data to obtain the first currents, and calculating the mean value of all rotating speeds in the multiple groups of first collected data to obtain the first rotating speed.

9. The apparatus of claim 6, wherein the fourth acquisition unit comprises:

the second setting unit is used for setting the current of the target equipment as the sum of the final regulating current of the electromagnetic valve and a second preset value;

the third acquisition subunit is used for executing the acquisition operation for preset times to obtain a plurality of groups of second acquisition data;

and the second calculating unit is used for calculating the mean value of all currents in the multiple groups of second collected data and the mean value of all rotating speeds in the multiple groups of second collected data respectively to obtain a third current and a third rotating speed.

10. The apparatus of claim 6, further comprising:

a third setting unit configured to set the current of the target device to the third current before the second adjusting unit performs the step-wise reduction of the current of the target device.

Technical Field

The present disclosure relates to current detection technologies, and in particular, to a method and an apparatus for detecting a current of a series solenoid valve.

Background

In the hydraulic power system, the displacement of the hydraulic pump and the hydraulic motor is controlled by controlling the current of the hydraulic pump and the hydraulic motor. Specifically, the control of the displacement of the hydraulic pump and the hydraulic motor is realized by controlling the current of the solenoid valve of the hydraulic pump and the current of the solenoid valve of the hydraulic motor. In order to accurately control the displacement of the hydraulic pump and the hydraulic motor, the start-regulation current and the final-regulation current of the electromagnetic valves of the hydraulic pump and the hydraulic motor need to be calibrated respectively.

Nowadays, a hydraulic power system usually includes only one hydraulic pump and one hydraulic motor, so for the hydraulic pump or the hydraulic motor, the starting adjustment current and the final adjustment current of the hydraulic pump or the hydraulic motor can be obtained correspondingly through the current when the hydraulic motor starts to reach the corresponding starting adjustment rotating speed and the final adjustment current calibrated by the electromagnetic valve.

However, there may be a case where a plurality of hydraulic pumps and a plurality of hydraulic motors are included in one hydraulic power system, that is, a case where two hydraulic pumps or two hydraulic motors are connected in series to form a solenoid valve, and the start and final control of the two hydraulic pumps or the two hydraulic motors is involved, so that four currents, i.e., a small start control current, a large start control current, a small final control current, and a large final control current, are involved in controlling the solenoid valve. With the above approach for a single solenoid valve, only a small trim current is available, and there is also a lack of an effective and accurate way to detect these four currents today.

Disclosure of Invention

Based on the defects of the prior art, the application provides a current detection method and a current detection device for a series electromagnetic valve, so as to solve the problem that the prior art lacks of effectively detecting the start-up current and the final-adjustment current of the series electromagnetic valve.

In order to achieve the above object, the present application provides the following technical solutions:

the application provides a current detection method of a series electromagnetic valve in a first aspect, which comprises the following steps:

gradually increasing the current of the target equipment from zero until the rotation speed of the hydraulic motor is detected to be greater than the starting rotation speed of the target equipment; wherein the target equipment is the hydraulic motor or a hydraulic pump in a hydraulic power system to which the hydraulic motor belongs;

acquiring the actual current of the target equipment to obtain the minimum starting current;

setting the current of the target equipment as a target current, and executing acquisition operation to obtain a first current and a first rotating speed; wherein the collecting operation is to collect an actual current of the target device and an actual rotational speed of the hydraulic motor; the two series electromagnetic valves corresponding to the target equipment are both started and adjusted under the target current;

setting the current of the target equipment as the difference value between the single final adjustment current of the electromagnet and a first preset value, and executing the acquisition operation to obtain a second current and a second rotating speed;

setting the current of the target equipment as the sum of the final regulation current of a single electromagnetic valve and a second preset value, and executing the acquisition operation to obtain a third current and a third rotating speed;

gradually reducing the current of the target device until the rotation speed of the hydraulic motor is detected to be less than the third rotation speed;

executing the acquisition operation to obtain a maximum final adjusting current and a fourth rotating speed;

determining a current value in an intersection point coordinate of a first straight line where a first coordinate is located and a target straight line as a first synchronous current, and determining a current value in an intersection point coordinate of a second straight line where a fourth coordinate is located and the target straight line as a first final current;

wherein the first coordinate comprises the minimum key-on current and a key-on speed of the target device; the fourth coordinate comprises the maximum final regulation current and the fourth rotation speed; the target straight line is a straight line where a second coordinate and a third coordinate are located together, and the second coordinate comprises the first current and the first rotating speed; the third coordinate comprises the second current and the second rotational speed; the slope of the target straight line is twice that of the first straight line, and the slopes of the first straight line and the second straight line are equal.

Optionally, in the above method for detecting a current of a series solenoid valve, the setting the current of the target device to a target current includes:

and setting the current of the target device as the sum of the minimum start-up current and a third preset value.

Optionally, in the above method for detecting a current of a series solenoid valve, setting a current of the target device as a target current, and performing a collecting operation to obtain a first current and a first rotation speed includes:

setting a current of the target device to a target current;

executing the acquisition operation for preset times to obtain multiple groups of first acquisition data;

calculating the mean value of all currents in the multiple groups of first collected data to obtain the first currents, and calculating the mean value of all rotating speeds in the multiple groups of first collected data to obtain the first rotating speed.

Optionally, in the above method for detecting current of serially connected solenoid valves, the setting the current of the target device as a sum of a final control current of a single solenoid valve and a second preset value, and performing the collecting operation to obtain a third current and a third rotation speed includes:

setting the current of the target equipment as the sum of the final regulating current of the electromagnetic valve and a second preset value;

executing the acquisition operation for preset times to obtain multiple groups of second acquisition data;

and respectively calculating the mean value of all currents in the multiple groups of second collected data and the mean value of all rotating speeds in the multiple groups of second collected data to obtain a third current and a third rotating speed.

Optionally, in the above method for detecting a current of a series solenoid valve, before the step of reducing the current of the target device until the rotation speed of the hydraulic motor is detected to be less than the third rotation speed, the method further includes:

setting the current of the target device to the third current.

The present application provides in a second aspect a current detection device for series connected solenoid valves, comprising:

a first adjusting unit for gradually increasing the current of a target device from zero until detecting that the rotation speed of a hydraulic motor is greater than the starting adjustment rotation speed of the target device; wherein the target equipment is the hydraulic motor or a hydraulic pump in a hydraulic power system to which the hydraulic motor belongs;

the first acquisition unit is used for acquiring the actual current of the target equipment to obtain the minimum starting current;

the second acquisition unit is used for setting the current of the target equipment as a target current and executing acquisition operation to obtain a first current and a first rotating speed; wherein the collecting operation is to collect an actual current of the target device and an actual rotational speed of the hydraulic motor; the two series electromagnetic valves corresponding to the target equipment are both started and adjusted under the target current;

the third acquisition unit is used for setting the current of the target equipment as the difference value between the single final modulation current of the electromagnet and a first preset value, and executing the acquisition operation to obtain a second current and a second rotating speed;

the fourth acquisition unit is used for setting the current of the target equipment as the sum of the final regulation current of the single electromagnetic valve and a second preset value, and executing the acquisition operation to obtain a third current and a third rotating speed;

a second adjustment unit for gradually reducing the current of the target device until it is detected that the rotation speed of the hydraulic motor is less than the third rotation speed;

the fifth acquisition unit is used for executing the acquisition operation to obtain the maximum final adjustment current and the fourth rotating speed;

the determining unit is used for determining a current value in an intersection point coordinate of a first straight line where the first coordinate is located and the target straight line as a first synchronous regulation current, and determining a current value in an intersection point coordinate of a second straight line where the fourth coordinate is located and the target straight line as a first final regulation current;

wherein the first coordinate comprises the minimum key-on current and a key-on speed of the target device; the fourth coordinate comprises the maximum final regulation current and the fourth rotation speed; the target straight line is a straight line where a second coordinate and a third coordinate are located together, and the second coordinate comprises the first current and the first rotating speed; the third coordinate comprises the second current and the second rotational speed; the slope of the target straight line is twice that of the first straight line, and the slopes of the first straight line and the second straight line are equal.

Optionally, in the above current detection apparatus of a series solenoid valve, the second collecting unit is configured to, when the current of the target device is set as a target current,:

and setting the current of the target device as the sum of the minimum start-up current and a third preset value.

Optionally, in the above current detection device of a series solenoid valve, the second collecting unit includes:

a first setting unit for setting a current of the target device as a target current;

the second acquisition subunit is used for executing the acquisition operation for preset times to obtain multiple groups of first acquisition data;

the first calculating unit is used for calculating the mean value of all currents in the multiple groups of first collected data to obtain the first currents, and calculating the mean value of all rotating speeds in the multiple groups of first collected data to obtain the first rotating speed.

Optionally, in the above current detection device of a series solenoid valve, the fourth collecting unit includes:

the second setting unit is used for setting the current of the target equipment as the sum of the final regulating current of the electromagnetic valve and a second preset value;

the third acquisition subunit is used for executing the acquisition operation for preset times to obtain a plurality of groups of second acquisition data;

and the second calculating unit is used for calculating the mean value of all currents in the multiple groups of second collected data and the mean value of all rotating speeds in the multiple groups of second collected data respectively to obtain a third current and a third rotating speed.

Optionally, the current detection device for series electromagnetic valves further includes:

a third setting unit configured to set the current of the target device to the third current before the second adjusting unit performs the step-wise reduction of the current of the target device.

According to the current detection method of the series electromagnetic valve, the current of the target equipment is gradually increased from zero until the rotation speed of the hydraulic motor is detected to be larger than the starting adjustment rotation speed of the target equipment, the actual current of the target equipment is collected, and the minimum starting adjustment current is obtained. And setting the current of the target equipment as the sum of the final regulation current of the single electromagnetic valve and a second preset value, and executing acquisition operation to obtain a third current and a third rotating speed so as to acquire the maximum final regulation current and a fourth rotating speed by gradually reducing the current of the target equipment until the third rotating speed is reached. Thereby obtaining the minimum starting current and the maximum final current of the target device. Then, the current of the target equipment is set as the target current, acquisition operation is carried out to obtain a first current and a first rotating speed, the target equipment is set as the difference value between the final regulation current of a single electromagnet and a first preset value, and a second current and a second rotating speed are acquired. Finally, the collected minimum starting current and the starting rotating speed of the target equipment are used as a first coordinate, the maximum final current and the fourth rotating speed are used as a fourth coordinate, the first current and the first rotating speed are used as a second coordinate, the second current and the second rotating speed are used as a third coordinate, and determining that the straight line where the second coordinate and the third coordinate are located is a target straight line, the straight line where the first coordinate is located is a first straight line, the straight line where the fourth coordinate is located is a second straight line, and the slope of the target straight line is twice of that of the first straight line and the second straight line, finally, the current value in the intersection point coordinate of the first straight line and the target straight line is determined as the first start-up current to obtain larger start-up current, and determining the current value in the intersection point coordinate of the second straight line and the target straight line as a first final adjusting current to obtain a smaller final adjusting current, therefore, the starting current and the final current of the series electromagnetic valves can be effectively and accurately measured.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, it is obvious that the drawings in the following description are only embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

Fig. 1 is a flowchart of a current detection method for series-connected solenoid valves according to an embodiment of the present disclosure;

FIG. 2 is a flow chart of a method for collecting a first current and a first rotational speed according to an embodiment of the present disclosure;

FIG. 3 is a flowchart of a method for collecting a third current and a fourth rotational speed according to an embodiment of the present disclosure;

FIG. 4 is a graph of current curves for a hydraulic pump according to an embodiment of the present disclosure;

fig. 5 is a schematic structural diagram of a current detection device of a series solenoid valve according to another embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In this application, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The embodiment of the application provides a current detection method of series electromagnetic valves, which is mainly applied to detecting the start-up current and the final-adjustment current of the electromagnetic valves of the series hydraulic pumps and detecting the start-up current and the final-adjustment current of the electromagnetic valves of the series hydraulic motors. As shown in fig. 1, a method for detecting a current of a series solenoid valve provided in an embodiment of the present application includes the following steps:

and S101, gradually increasing the current of the target equipment from zero until the rotation speed of the hydraulic motor is detected to be greater than the starting rotation speed of the target equipment.

It should be noted that, in the present embodiment, the current of the target device is the current of the solenoid valve in the target device. Also, since the target devices are connected in series, i.e., the solenoids are connected in series, the currents of the two solenoids are equal, i.e., the currents of the two target devices are equal.

Wherein, the starting adjusting rotating speed is the rotating speed output by the hydraulic motor when the target equipment is started. The target device is the hydraulic motor with the detected rotating speed or a hydraulic pump in a hydraulic power system to which the hydraulic motor belongs. The hydraulic power system includes a hydraulic pump and a hydraulic motor, and the hydraulic motor is driven by high-speed liquid generated by pressurizing the liquid by the hydraulic pump.

Specifically, since the starting rotational speed corresponding to the hydraulic pump is 0, when the target device is the hydraulic pump, step S101 is: and gradually increasing the current of the hydraulic pump from zero until the rotation speed of the hydraulic motor belonging to the same hydraulic power system is detected to be greater than 0, stopping increasing the current at the moment, and executing the step S102.

Since the rotation speed of the hydraulic motor is not completely positively correlated with the displacement of the hydraulic motor, empirical coefficient fitting needs to be adopted for the corresponding start-up and transition. Specifically, the corresponding starting and adjusting rotation speed of the hydraulic motor is as follows: the hydraulic pump in the same hydraulic power system just has the product of the rotation speed of the hydraulic motor at the maximum arrangement and the empirical coefficient. Or simply by increasing the current of the hydraulic pump, the maximum speed that can be reached by the hydraulic motor is multiplied by an empirical factor, which is typically 1.03, i.e. the third speed obtained by implementing the present solution when the target device is a hydraulic pump. It should be noted that this is not the maximum rotation speed of the hydraulic motor, and the rotation speed of the hydraulic motor is also increased when the current of the hydraulic motor is increased. Likewise, when the target device is a hydraulic motor, step S101 is specifically: the current of the hydraulic motor is gradually increased from zero until the rotation speed of the hydraulic motor is detected to be greater than the self-regulation rotation speed, at which time the current is stopped to be increased, and step S102 is executed.

And S102, collecting the actual current of the target equipment to obtain the minimum starting current.

It should be noted that the actual current of the target device collected at this time is the smaller start-up current of the target device.

Optionally, in order to make the minimum start-up current more accurate, the actual current of the target device may be collected for multiple times, and then the collected multiple actual currents are averaged, and the averaged value is used as the minimum start-up current.

S103, setting the current of the target equipment as a target current, collecting the actual current of the target equipment and the actual rotating speed of the hydraulic motor to obtain a first current and a first rotating speed, wherein the two series-connected electromagnetic valves corresponding to the target equipment are adjusted under the target current.

It should be noted that, in the present application, the operation of acquiring the actual current of the target device and the actual rotation speed of the hydraulic motor is to perform the acquisition operation.

The two series electromagnetic valves corresponding to the target equipment refer to electromagnetic valves in the two target equipment which are connected in series.

It should be noted that, under the target current, both the two series-connected solenoid valves corresponding to the target device are started to be adjusted, but the target current is not yet the maximum, and the target current is smaller than the final adjustment current.

Alternatively, one specific implementation of setting the current of the target device as the target current in step S103 may be: and setting the current of the target equipment as the sum of the minimum start-up current and a third preset value.

It should be noted that the target current is necessarily larger than the minimum start-up current, so that the current of the target device can more conveniently reach the target current meeting the requirement by setting the current of the target device to be the sum of the minimum start-up current and the third preset value. The third preset value is obtained according to the characteristics of the solenoid valve of the target device, and may be, for example, 50 milliamperes.

Optionally, a specific implementation manner of step S103, as shown in fig. 2, includes the following steps:

s201, setting the current of the target device as the target current.

After the current of the target device and the rotation speed of the hydraulic motor are stabilized, step S202 is executed.

S202, executing the collection operation for preset times to obtain multiple groups of first collected data.

Wherein the collecting operation is to collect an actual current of the target device and an actual rotation speed of the hydraulic motor. Each set of collected data comprises the actual current of one target device and the actual rotating speed of one hydraulic motor, which are collected by performing one collecting operation.

S203, calculating the mean value of all currents in the multiple groups of first collected data to obtain first currents, and calculating the mean value of all rotating speeds in the multiple groups of first collected data to obtain first rotating speeds.

S104, setting the current of the target equipment as the difference value between the final regulation current of the single electromagnet and the first preset value, and acquiring the actual current of the target equipment and the actual rotating speed of the hydraulic motor to obtain a second current and a second rotating speed.

The final regulation current of a single solenoid valve refers to the final regulation current of the solenoid valve in a target device under the condition that the solenoid valves are not connected in series. When the current of the target equipment is set as the difference value between the final regulation current of a single electromagnet and the first preset value, the two series-connected electromagnetic valves are started to regulate, but all the electromagnetic valves do not reach the final regulation state. Also, the first preset value is also obtained according to the characteristics of the solenoid valve of the target apparatus, and may be equal to the third preset value.

It should be noted that, in order to obtain the relationship between the current and the rotation speed when both the two series-connected solenoid valves corresponding to the target device have been started and have not all reached the final regulation, so as to obtain the target straight line, it is necessary to determine two sets of current and rotation speed parameters when both the two series-connected solenoid valves have been started and have not all reached the final regulation, and step S103 obtains a set of parameters for solving the minimum starting regulation current, so in step S104, another set of parameters is collected.

It should be further noted that, the steps S103 and S104 are two relatively independent steps, so that the step S104 may also be executed before the step S103, or both the steps may be executed simultaneously, and the execution sequence in the embodiment of the present application is only one optional execution sequence.

And S105, setting the current of the target equipment as the sum of the final regulation current of the single electromagnetic valve and a second preset value, and acquiring the actual current of the target equipment and the actual rotating speed of the hydraulic motor to obtain a third current and a third rotating speed.

The second preset value is also selected based on the current characteristic of the solenoid valve, and may be equal to the first preset value and the third preset value.

It should be noted that, when the current of the target device is set as the sum of the final regulation current of a single electromagnetic valve and the second preset value, it can be effectively ensured that both the electromagnetic valves are in the final regulation state, and at this time, the current of the target device is increased, and the rotation speed of the hydraulic motor is not increased, so the main objective of executing step S105 is to determine the maximum rotation speed that can be reached when the series electromagnetic valve is in the complete final regulation, that is, the third rotation speed. Since the set current is larger than the final regulation current of a single electromagnetic valve, the obtained third current is larger than the maximum final regulation current. And if the target device is a hydraulic pump, the hydraulic pump reaches the maximum displacement at this time.

It should be further noted that step S105 and step S104 are also two relatively independent steps, so step S105 may also be executed before step S104, or both steps may be executed simultaneously, and the execution sequence in the embodiment of the present application is only one of optional execution sequences.

Optionally, in another embodiment of the present application, as shown in fig. 3, a specific implementation manner of step S105 includes the following steps:

and S301, setting the current of the target device as the sum of the final regulating current of the solenoid valve and a second preset value.

Specifically, after the current of the target device and the rotation speed of the hydraulic motor are stabilized, step S302 is executed.

And S302, executing the preset times of acquisition operation to obtain multiple groups of second acquisition data.

Wherein the collecting operation is to collect an actual current of the target device and an actual rotation speed of the hydraulic motor. Each set of collected data comprises the actual current of one target device and the actual rotating speed of one hydraulic motor, which are collected by performing one collecting operation.

And S303, respectively calculating the mean value of all currents in the multiple groups of second collected data and the mean value of all rotating speeds in the multiple groups of second collected data to obtain a third current and a third rotating speed.

And S106, gradually reducing the current of the target equipment until the rotation speed of the hydraulic motor is detected to be less than the third rotation speed.

It should be noted that, since the rotation speed of the hydraulic motor is detected in real time, the rotation speed less than the third rotation speed is only a small difference from the third rotation speed and can be ignored.

In order to make the rotation speed of the hydraulic motor rapidly smaller than the fourth rotation speed, optionally before executing step S106, it may also be executed: and setting the current of the target device as the sum of the final regulating current of the single electromagnetic valve and the second preset value.

By setting the current of the target apparatus to the third current, the rotation speed of the hydraulic motor is brought close to the fourth rotation speed, so that the rotation speed of the hydraulic motor is rapidly increased to the fourth rotation speed while the current of the target apparatus is gradually increased.

Specifically, when it is detected that the rotation speed of the hydraulic motor is less than the fourth rotation speed, the increase of the current of the target device is stopped, and step S106 is executed after the current of the target device and the rotation speed of the hydraulic motor are stabilized.

Of course, it is also possible to set the current of the target device to the difference between the terminal current of the single solenoid valve and the fourth preset value, and then increase the current of the target device stepwise until it is detected that the rotation speed of the hydraulic motor is equal to or greater than the third rotation speed.

The value can be taken according to the characteristics of the electromagnetic valve, and the second preset value, the third preset value and the fourth preset value can be the same value, for example, all values are 50 milliamperes.

And S107, acquiring the actual current of the target equipment and the actual rotating speed of the hydraulic motor to obtain the maximum final speed and the fourth rotating speed.

Since the third rotation speed is the maximum rotation speed reached, when the rotation speed just reaches the third rotation speed, the current of the target device is the maximum final regulation current. Although the difference between the acquired fourth rotation speed and the third rotation speed is a certain value, the difference is relatively small and can be ignored, so that the fourth rotation speed is equal to the third rotation speed.

Optionally, the actual currents of multiple groups of target devices and the actual rotation speed of the hydraulic motor may also be collected, and then an average value of the collected actual currents and the collected actual rotation speed is calculated to obtain the maximum final regulation current and the fourth rotation speed.

S108, determining a current value in the coordinate of the intersection point of the first straight line where the first coordinate is located and the target straight line as a second starting adjusting current, and determining a current value in the coordinate of the intersection point of the second straight line where the fourth coordinate is located and the target straight line as a first final adjusting current.

It should be noted that, in the present application, a two-dimensional coordinate system is constructed, and two coordinate axes represent the actual current of the target device and the actual rotation speed of the hydraulic motor, respectively. Thus, the acquired data can be plotted in a coordinate system. The obtained coordinates of the intersection also include a current value and a rotation speed value.

Specifically, the target straight line is a straight line where the second coordinate and the third coordinate are located together, and the straight line is determined by the two points, and the target straight line refers to a unique straight line determined by the second coordinate and the third coordinate. The second coordinate comprises a first current and the first rotating speed, the third coordinate comprises a second current and a second rotating speed, and therefore, a straight line from the second coordinate to the third coordinate represents that the electromagnetic valves connected in series are all started and adjusted, but the linear relation between the current of the target equipment and the rotating speed of the hydraulic motor is not completely achieved when the final adjustment is not completely achieved.

Specifically, the first straight line where the first coordinate is located refers to passing through the first coordinate point, and the first coordinate includes the collected minimum start-up current and the start-up rotation speed of the target device, that is, specifically, the abscissa of the first coordinate is the minimum start-up current, and the ordinate is the start-up rotation speed of the target device. Since the target straight line represents the linear relationship between the current of the target equipment and the hydraulic motor when the series solenoid valves are all started, and the first straight line where the first coordinate is located represents the linear relationship between the current of the target equipment and the hydraulic motor when the two series solenoid valves are not completely started, namely the current curve when the single solenoid valve works, the slope of the target straight line is twice of that of the first straight line. Therefore, the intersection point of the first straight line and the target straight line is the second starting point, and the coordinates of the intersection point are the large starting current of the target device and the rotation speed of the hydraulic motor under the current, that is, the second starting current is the large starting current of the target device.

The second straight line on which the fourth coordinate is located refers to a straight line passing through the fourth coordinate. Similarly, since the fourth coordinate includes the maximum final adjustment current and the fourth rotation speed, that is, the current when the series solenoid valves have all reached the final adjustment and the rotation speed of the hydraulic motor, the slope of the second line is a line half of the slope of the target line, that is, the slope of the first line is equal to the slope of the second line. Therefore, the intersection point of the second straight line and the target straight line is another final regulation point of the target device, so the current value of the intersection point coordinate is a small final regulation current of the target device, and the rotating speed value in the intersection point coordinate is a rotating speed with developed hydraulic pressure at the current value, namely the first final regulation current is the small final regulation current of the target device.

Since the slope of the target straight line can be obtained from the second coordinate and the third coordinate, the slopes of the first straight line and the second straight line can be further determined, so that the first straight line and the second straight line are determined, and for the fifth coordinate corresponding to the third current and the third rotation speed, since the rotation speeds of the fourth coordinate and the fifth coordinate are equal, and as the current increases, the rotation speed does not increase any more, the straight line is a horizontal straight line, so that the current curves of the target device are obtained by combining the straight lines.

For example, as shown in fig. 4, if the target device is a hydraulic pump, the first coordinate is a0, the second coordinate is T1, the third coordinate is T2, the fourth coordinate is A3, and the fifth coordinate is T3. And the first coordinate A0 is the minimum starting point of the hydraulic pump, and the fourth coordinate A3 is the maximum final point of the hydraulic pump, so after A3, the rotating speed of the hydraulic motor does not change along with the increase of the current of the hydraulic pump. By using the coordinate values of T1 and T2, the slope 2k of a target straight line L passing through T1 and T2 can be obtained, so that a first straight line L1 passing through A0 and having the slope of k can be determined, an intersection point A1 of the first straight line L1 and the target straight line L is obtained, and a larger starting point of the hydraulic pump is obtained. Similarly, a second straight line L2 passing through A3 and having a slope k can be determined, and an intersection point a2 of the second straight line L2 and the target straight line L is obtained, that is, a small starting point of the hydraulic pump is obtained. And the current of T3 is greater than that of A3, but the rotation speed is the same, so the straight line L3 passing through T3 and A3 is a horizontal straight line. As shown in fig. 4, the straight line a0-a1-a2-A3-T3, i.e., the curve formed by L1, L2, and L3, is the current curve of the hydraulic pump.

According to the current detection method of the series electromagnetic valve, the current of the target equipment is gradually increased from zero until the rotation speed of the hydraulic motor is detected to be larger than the starting adjustment rotation speed of the target equipment, the actual current of the target equipment is collected, and the minimum starting adjustment current is obtained. And setting the current of the target equipment as the sum of the final regulation current of the single electromagnetic valve and a second preset value, and executing acquisition operation to obtain a third current and a third rotating speed so as to acquire the maximum final regulation current and a fourth rotating speed by gradually reducing the current of the target equipment until the third rotating speed is reached. Thereby obtaining the minimum starting current and the maximum final current of the target device. Then, setting the current of the target equipment as a target current, executing acquisition operation to obtain a first current and a first rotating speed, gradually increasing the current of the target equipment, setting the current of the target equipment as a difference value between the final regulation current of a single electromagnet and a first preset value, and acquiring a second current and a second rotating speed. Finally, the collected minimum starting current and the starting rotating speed of the target equipment are used as a first coordinate, the maximum final current and the fourth rotating speed are used as a fourth coordinate, the first current and the first rotating speed are used as a second coordinate, the second current and the second rotating speed are used as a third coordinate, and determining that the straight line where the second coordinate and the third coordinate are located is a target straight line, the straight line where the first coordinate is located is a first straight line, the straight line where the fourth coordinate is located is a second straight line, and the slope of the target straight line is twice of that of the first straight line and the second straight line, finally, the current value in the intersection point coordinate of the first straight line and the target straight line is determined as the first start-up current to obtain larger start-up current, and determining the current value in the intersection point coordinate of the second straight line and the target straight line as a first final adjusting current to obtain a smaller final adjusting current, therefore, the starting current and the final current of the series electromagnetic valves can be effectively and accurately measured.

Another embodiment of the present application provides a current detection apparatus for a series solenoid valve, as shown in fig. 5, including the following units:

a first regulating unit 501 for gradually increasing the current of the target device from zero until it is detected that the rotational speed of the hydraulic motor is greater than the starting rotational speed of the target device.

The target equipment is a hydraulic motor or a hydraulic pump in a hydraulic power system to which the hydraulic motor belongs.

The first acquisition unit 502 is used for acquiring the actual current of the target device to obtain the minimum start-up current.

The second collecting unit 503 is configured to set the current of the target device as a target current, and perform a collecting operation to obtain a first current and a first rotation speed.

Wherein the collecting operation is to collect an actual current of the target device and an actual rotation speed of the hydraulic motor. And the two series electromagnetic valves corresponding to the target equipment are all started and adjusted under the target current.

The third collecting unit 504 is configured to set the current of the target device to a difference between the final adjustment current of a single electromagnetic and the first preset value, and perform a collecting operation to obtain a second current and a second rotation speed.

And a fourth collecting unit 505, configured to set the current of the target device to be the sum of the final adjustment current of the single solenoid valve and the second preset value, and perform a collecting operation to obtain a third current and a fourth rotation speed.

A second regulating unit 506 for gradually increasing the current of the target device until it is detected that the rotational speed of the hydraulic motor is less than the third rotational speed.

A fifth collecting unit 507, configured to perform a collecting operation to obtain a second current and a second rotation speed;

a determining unit 508, configured to determine a current value in an intersection coordinate of a first straight line where the first coordinate is located and the target straight line as a first final modulation current, and determine a current value in an intersection coordinate of a second straight line where the fourth coordinate is located and the target straight line as a first final modulation current;

wherein the first coordinate comprises a minimum start-up current and a start-up rotation speed of the target device; the fourth coordinate comprises the maximum final current and a fourth rotating speed; the target straight line is a straight line where a second coordinate and a third coordinate are located together, and the second coordinate comprises a first current and a first rotating speed; the third coordinate comprises a second current and a second rotating speed; the slope of the target straight line is twice that of the first straight line, and the slopes of the first straight line and the second straight line are equal.

Optionally, in the current detection apparatus for a series solenoid valve provided in another embodiment of the present application, when the second collecting unit executes setting of the current of the target device as the target current, the second collecting unit is configured to:

and setting the current of the target equipment as the sum of the minimum start-up current and a third preset value.

Optionally, in a current detection apparatus of a series solenoid valve provided in another embodiment of the present application, the second collecting unit includes the following units:

a first setting unit for setting a current of the target device as a target current.

And the second acquisition subunit is used for executing acquisition operation for preset times to obtain multiple groups of first acquisition data.

The first calculating unit is used for calculating the mean value of all currents in the multiple groups of first collected data to obtain first currents and calculating the mean value of all rotating speeds in the multiple groups of first collected data to obtain first rotating speeds.

Optionally, in a current detection apparatus of a series solenoid valve provided in another embodiment of the present application, a fourth collecting unit includes the following units:

and the second setting unit is used for setting the current of the target equipment as the sum of the final regulating current of the electromagnetic valve and a second preset value.

And the third acquisition subunit is used for executing acquisition operation for preset times to obtain multiple groups of second acquisition data.

And the second calculating unit is used for calculating the mean value of all currents in the multiple groups of second collected data and the mean value of all rotating speeds in the multiple groups of second collected data respectively to obtain a third current and a third rotating speed.

Optionally, in a current detection apparatus of series connected solenoid valves provided in another embodiment of the present application, the apparatus further includes:

a third setting unit configured to set the current of the target device to the third current before the second adjusting unit performs the step-up of the current of the target device.

It should be noted that, in the foregoing embodiments of the present application, the specific working processes of each unit may refer to the implementation processes of the corresponding steps in the foregoing method embodiments, and therefore, the detailed description is omitted here.

Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative components and steps have been described above generally in terms of their functionality in order to clearly illustrate this interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.