阅读说明：本技术 一种控制方法、控制系统及电动阀 (Control method, control system and electric valve ) 是由 不公告发明人 于 2019-06-03 设计创作，主要内容包括：一种控制方法、控制系统及电动阀,控制方法包括获取实际测量的设定参数曲线；其中,设定参数曲线包括电动阀的位置与设定参数的对应关系,设定参数曲线包括第一端点至第二端点的第一曲线段和第二端点至第三端点的第二曲线段；根据第二曲线段获取单位设定参数；根据单位设定参数和第一曲线段获取插值设定参数点；将插值设定参数点插入第一曲线段,并将第一端点、插值设定参数点和第二端点作为依次相邻的设定参数点以使实际测量的设定参数曲线形成修正设定参数曲线；根据修正设定参数曲线控制电动阀运行。这样,有利于提高电动阀的设定参数的均匀程度,改善电动阀的设定参数波动的问题。(A control method, a control system and an electric valve are provided, wherein the control method comprises the steps of obtaining a set parameter curve of actual measurement; the setting parameter curve comprises a corresponding relation between the position of the electric valve and a setting parameter, and the setting parameter curve comprises a first curve section from a first end point to a second end point and a second curve section from the second end point to a third end point; acquiring unit setting parameters according to the second curve segment; obtaining interpolation setting parameter points according to the unit setting parameters and the first curve segment; inserting the interpolation setting parameter points into the first curve segment, and taking the first end point, the interpolation setting parameter points and the second end point as the adjacent setting parameter points in sequence to enable the actually measured setting parameter curve to form a correction setting parameter curve; and controlling the electric valve to operate according to the corrected set parameter curve. Therefore, the uniformity of the set parameters of the electric valve is improved, and the problem of the fluctuation of the set parameters of the electric valve is solved.)

1. A control method capable of controlling an electrically operated valve, characterized by comprising:

acquiring a set parameter curve of actual measurement; the set parameter curve comprises a corresponding relation between the position of the electric valve and set parameters, and comprises a first curve section from a first end point to a second end point and a second curve section from the second end point to a third end point;

acquiring unit setting parameters according to the second curve segment;

obtaining interpolation setting parameter points according to the unit setting parameters and the first curve segment;

inserting the interpolation setting parameter points into the first curve segment, and taking the first endpoint, the interpolation setting parameter points and the second endpoint as the adjacent setting parameter points in sequence so as to enable the actually measured setting parameter curve to form a modified setting parameter curve;

and controlling the electric valve to operate according to the corrected set parameter curve.

2. The control method according to claim 1, wherein said obtaining unit setting parameters from the second curve segment includes:

acquiring the unit setting parameter according to a second position and a second setting parameter corresponding to the second endpoint and a third position and a third setting parameter corresponding to the third endpoint;

the difference between the third position and the second position is a first difference, the difference between the third setting parameter and the second setting parameter is a second difference, and the unit setting parameter is equal to the ratio of the second difference to the first difference.

3. The control method of claim 1, wherein said obtaining interpolation set parameter points from the unit set parameter and the first curve segment comprises:

acquiring the number of interpolation setting parameter points to be inserted according to the unit setting parameters and the first curve segment;

and obtaining the interpolation setting parameter points according to the unit setting parameters, the first curve section and the number of the interpolation setting parameter points to be inserted.

4. The control method according to claim 3, wherein the obtaining the number of interpolation setting parameter points to be interpolated according to the unit setting parameter and the first curve segment comprises:

acquiring the number of the interpolation setting parameter points to be inserted according to a second setting parameter corresponding to the second endpoint, a first setting parameter corresponding to the first endpoint and the unit setting parameter;

the difference value between the second setting parameter and the first setting parameter is a third difference value, and the number of the interpolation setting parameter points to be inserted is equal to the ratio of the third difference value to the unit setting parameter minus 1.

5. The control method according to claim 3, wherein the obtaining the interpolation setting parameter points according to the unit setting parameter, the first curve segment, and the number of the interpolation setting parameter points to be inserted comprises:

respectively taking La +1 pf, … … and La + n pf as setting parameters corresponding to the interpolation setting parameter points; la is a first setting parameter corresponding to the first endpoint, n is the number of interpolation setting parameter points needing to be inserted, n is a positive integer, pf is the unit setting parameter, and La + n pf is smaller than a second setting parameter corresponding to the second endpoint;

and setting parameter points, of which the setting parameters are equal to the setting parameters corresponding to the interpolation setting parameter points, on the first curve segment are used as the interpolation setting parameter points.

6. The control method according to claim 1, wherein the difference between the positions of the electrically operated valve corresponding to adjacent set parameter points corresponds to one micro-step of a stepping motor in the electrically operated valve.

7. The method of claim 1, wherein the difference between the setting parameters for one microstep of the stepper motor in the electrically operated valve in the second curve segment is greater than 4% of the difference between the third setting parameter corresponding to the third endpoint and the first setting parameter corresponding to the first endpoint.

8. The control method according to claim 1, wherein the electric valve comprises an electronic expansion valve including a valve spool, the setting parameter comprises a flow rate, and the setting parameter curve comprises a correspondence relationship between a position of the valve spool and the flow rate.

9. The control method according to claim 8, wherein the electronic expansion valve further comprises a motor, the setting parameter further comprises a microstep value of the motor, the position of the valve element is determined by the microstep value of the motor, the setting parameter curve further comprises a corresponding relationship between the microstep value of the motor and a flow rate, and the operation of the electronic expansion valve is made to conform to the corrected setting parameter curve by adjusting the microstep value of the motor.

10. A control method capable of controlling an electrically operated valve, characterized by comprising:

controlling the operation of the electric valve to accord with the corrected set parameter curve;

the correction setting parameter curve is prestored in a control system for controlling the operation of the electric valve, the correction setting parameter curve changes along with the change of the setting parameter curve, the setting parameter curve comprises the corresponding relation between the position of the electric valve and the setting parameter, and the setting parameter curve comprises a first curve section from a first end point to a second end point and a second curve section from the second end point to a third end point;

the correction setting parameter curve is obtained by obtaining a unit setting parameter according to the second curve segment, obtaining an interpolation setting parameter point according to the unit setting parameter and the first curve segment, inserting the interpolation setting parameter point into the first curve segment, and taking the first endpoint, the interpolation setting parameter point and the second endpoint as the adjacent setting parameter points in sequence.

11. A control system capable of controlling an electrically operated valve, comprising:

the actual curve acquisition module is used for acquiring a set parameter curve of actual measurement; the set parameter curve comprises a corresponding relation between the position of the electric valve and set parameters, and comprises a first curve section from a first end point to a second end point and a second curve section from the second end point to a third end point;

the unit parameter acquisition module is used for acquiring unit setting parameters according to the second curve segment;

the interpolation parameter point acquisition module is used for acquiring interpolation setting parameter points according to the unit setting parameters and the first curve section;

a correction curve obtaining module, configured to insert the interpolation setting parameter point into the first curve segment, and use the first endpoint, the interpolation setting parameter point, and the second endpoint as sequentially adjacent setting parameter points, so that a actually measured setting parameter curve forms a correction setting parameter curve;

and the electric valve control module is used for controlling the electric valve to operate according to the corrected set parameter curve.

12. A control system capable of controlling an electrically operated valve, comprising:

the electric valve control module is used for controlling the operation of the electric valve to accord with the corrected set parameter curve;

the storage module is used for storing a correction setting parameter curve, the correction setting parameter curve changes along with the change of the setting parameter curve, the setting parameter curve comprises the corresponding relation between the position of the electric valve and a setting parameter, and the setting parameter curve comprises a first curve section from a first end point to a second end point and a second curve section from the second end point to a third end point; the correction setting parameter curve is obtained by obtaining a unit setting parameter according to the second curve segment, obtaining an interpolation setting parameter point according to the unit setting parameter and the first curve segment, inserting the interpolation setting parameter point into the first curve segment, and taking the first endpoint, the interpolation setting parameter point and the second endpoint as the adjacent setting parameter points in sequence.

13. An electrically operated valve comprising a stator assembly, a rotor assembly, a valve core and a circuit board assembly, wherein the stator assembly comprises a coil, the rotor assembly comprises a permanent magnet, the coil is electrically connected with the circuit board assembly, the coil generates an excitation magnetic field after being electrified, the rotor assembly operates in the excitation magnetic field, the position of the valve core is the position of the electrically operated valve, and the circuit board assembly is integrated with the control system according to claim 11 or 12.

Technical Field

The embodiment of the invention relates to the field of control, in particular to a control method, a control system and an electric valve.

Background

The electrically operated valve generally includes a controller, a stepping motor and a valve core, the controller sends a driving signal to the stepping motor to control the stepping motor to rotate, the stepping motor drives the valve core of the electrically operated valve to operate relative to the valve port, so that the valve port reaches a corresponding opening degree, the electrically operated valve may be, for example, an electronic expansion valve, and the adjustment of the flow rate of the working medium can be realized by adjusting the position of the valve core in the electronic expansion valve.

Generally, when a stepping motor is controlled in micro-steps, a sine step-shaped driving current is input to the stepping motor, theoretically, each micro-step of the stepping motor should have the same rotation angle under the action of the sine step-shaped driving current, the change of flow corresponding to each micro-step should be uniform, but is limited by the production process and the assembly precision of mechanical structures such as a rotor and a stator of the stepping motor, and in addition, a magnetic field generated by the rotor in the stepping motor and the matching between the rotor and the stator have deviation, so that when the stepping motor is controlled in micro-steps, the rotation angle corresponding to each micro-step is not uniform, the flow change corresponding to each micro-step is not uniform, the problem of flow fluctuation exists, and the control precision of an air conditioning system is influenced.

Disclosure of Invention

In view of this, embodiments of the present invention provide a control method, a control system and an electric valve, so that the fluctuation degree of the formed corrected setting parameter curve relative to the actually measured setting parameter curve is reduced, and the problem of the fluctuation of the setting parameter of the electric valve is solved.

In a first aspect, an embodiment of the present invention provides a control method, capable of controlling an electrically operated valve, where the control method includes:

acquiring a set parameter curve of actual measurement; the set parameter curve comprises a corresponding relation between the position of the electric valve and set parameters, and comprises a first curve section from a first end point to a second end point and a second curve section from the second end point to a third end point;

acquiring unit setting parameters according to the second curve segment;

obtaining interpolation setting parameter points according to the unit setting parameters and the first curve segment;

inserting the interpolation setting parameter points into the first curve segment, and taking the first endpoint, the interpolation setting parameter points and the second endpoint as the adjacent setting parameter points in sequence so as to enable the actually measured setting parameter curve to form a modified setting parameter curve;

and controlling the electric valve to rotate according to the corrected set parameter curve.

In a second aspect, an embodiment of the present invention further provides a control method, capable of controlling an electrically operated valve, where the control method includes:

controlling the operation of the electric valve to accord with the corrected set parameter curve;

the correction setting parameter curve is prestored in a control system for controlling the operation of the electric valve, the correction setting parameter curve changes along with the change of the setting parameter curve, the setting parameter curve comprises the corresponding relation between the position of the electric valve and the setting parameter, and the setting parameter curve comprises a first curve section from a first end point to a second end point and a second curve section from the second end point to a third end point;

the correction setting parameter curve is obtained by obtaining a unit setting parameter according to the second curve segment, obtaining an interpolation setting parameter point according to the unit setting parameter and the first curve segment, inserting the interpolation setting parameter point into the first curve segment, and taking the first endpoint, the interpolation setting parameter point and the second endpoint as the adjacent setting parameter points in sequence.

In a third aspect, an embodiment of the present invention further provides a control system, which is capable of controlling an electrically operated valve, and includes:

the actual curve acquisition module is used for acquiring a set parameter curve of actual measurement; the set parameter curve comprises a corresponding relation between the position of the electric valve and set parameters, and comprises a first curve section from a first end point to a second end point and a second curve section from the second end point to a third end point;

the unit parameter acquisition module is used for acquiring unit setting parameters according to the second curve segment;

the interpolation parameter point acquisition module is used for acquiring interpolation setting parameter points according to the unit setting parameters and the first curve section;

a correction curve obtaining module, configured to insert the interpolation setting parameter point into the first curve segment, and use the first endpoint, the interpolation setting parameter point, and the second endpoint as sequentially adjacent setting parameter points, so that a actually measured setting parameter curve forms a correction setting parameter curve;

and the electric valve control module is used for controlling the electric valve to rotate according to the corrected set parameter curve.

In a fourth aspect, an embodiment of the present invention further provides a control system, capable of controlling an electrically operated valve, including:

the electric valve control module is used for controlling the operation of the electric valve to accord with the corrected set parameter curve;

the storage module is used for storing a correction setting parameter curve, the correction setting parameter curve changes along with the change of the setting parameter curve, the setting parameter curve comprises the corresponding relation between the position of the electric valve and a setting parameter, and the setting parameter curve comprises a first curve section from a first end point to a second end point and a second curve section from the second end point to a third end point; the correction setting parameter curve is obtained by obtaining a unit setting parameter according to the second curve segment, obtaining an interpolation setting parameter point according to the unit setting parameter and the first curve segment, inserting the interpolation setting parameter point into the first curve segment, and taking the first endpoint, the interpolation setting parameter point and the second endpoint as the adjacent setting parameter points in sequence.

In a fifth aspect, an embodiment of the present invention further provides an electrically operated valve, including a stator assembly, a rotor assembly, a valve core, and a circuit board assembly, where the stator assembly includes a coil, the rotor assembly includes a permanent magnet, the coil is electrically connected to the circuit board assembly, the coil generates an excitation magnetic field after being energized, the rotor assembly rotates in the excitation magnetic field, the position of the valve core is the position of the electrically operated valve, and the circuit board assembly is integrated with the control system according to the third aspect or the fourth aspect.

The embodiment of the invention provides a control method, a control system and an electric valve, wherein the control method comprises the steps of obtaining a set parameter curve of actual measurement, wherein the set parameter curve comprises the corresponding relation between the position of the electric valve and set parameters, the set parameter curve comprises a first curve section from a first endpoint to a second endpoint and a second curve section from the second endpoint to a third endpoint, obtaining unit set parameters according to the second curve section, obtaining interpolation set parameter points according to the unit set parameters and the first curve section, inserting the interpolation set parameter points into the first curve section, taking the first endpoint, the interpolation set parameter points and the second endpoint as the adjacent set parameter points in sequence to enable the set parameter curve of the actual measurement to form a correction set parameter curve, and controlling the electric valve to operate according to the correction set parameter curve, namely, the electric valve operates by inserting the interpolation set parameter points into the first curve section and taking the first endpoint as the adjacent set parameter points, The interpolation setting parameter point and the second end point are used as the adjacent setting parameter points in sequence, so that the fluctuation degree of the formed correction setting parameter curve relative to the setting parameter curve is reduced, the electric valve is controlled to operate according to the correction setting curve, the uniformity degree of the setting parameters of the electric valve is improved, and the problem of the fluctuation of the setting parameters of the electric valve is solved.

Drawings

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

Fig. 1 is a schematic flow chart of a first control method according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a set parameter curve for actual measurement according to an embodiment of the present invention;

FIG. 3 is an enlarged partial view of the actual measured set-point parameter curve of FIG. 2;

fig. 4 is a schematic diagram of a modified setup parameter curve according to an embodiment of the present invention;

fig. 5 is a schematic flowchart of a second control method according to an embodiment of the present invention;

fig. 6 is a schematic flowchart of a third control method according to an embodiment of the present invention;

fig. 7 is a schematic diagram of a set parameter curve according to an embodiment of the present invention;

FIG. 8 is a schematic block diagram of a first control system provided in accordance with an embodiment of the present invention;

fig. 9 is a schematic structural diagram of an electrically operated valve according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described through embodiments with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. 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 invention.

Fig. 1 is a schematic flowchart of a first control method provided in an embodiment of the present invention, where the control method may be applied to a scenario where an electric valve needs to be controlled, and may be executed by a control system of the electric valve, where the control system may be executed in a software and/or hardware manner. As shown in fig. 1, the control method includes:

s101, acquiring a set parameter curve of actual measurement; the setting parameter curve comprises a corresponding relation between the position of the electric valve and the setting parameter, and the setting parameter curve comprises a first curve section from a first endpoint to a second endpoint and a second curve section from the second endpoint to a third endpoint.

And acquiring a set parameter curve of actual measurement, wherein the set parameter curve comprises the corresponding relation between the position of the electric valve and the set parameter. For example, the electric valve may be an electronic expansion valve, the setting parameter may include a flow rate, and the curve of the setting parameter may include a corresponding relationship between a position of the electronic expansion valve and the flow rate.

The electric valve generally comprises a controller, a stepping motor and a valve core, wherein the controller sends a driving signal to the stepping motor to control the stepping motor to rotate, the stepping motor drives the valve core of the electric valve to move relative to the valve port to enable the valve port to reach corresponding opening degree, the position of the electric valve can be understood as the position of the valve core of the electric valve, and the position of the valve core of the electric valve, the opening area of the valve port of the electric valve and the microstep number of the stepping motor are in linear relation, so that the position of the electric valve can be represented by the microstep number of the stepping motor in the electric valve.

Fig. 2 is a schematic diagram of an actually measured set parameter curve according to an embodiment of the present invention, fig. 3 is a partially enlarged view of the actually measured set parameter curve shown in fig. 2, an abscissa in fig. 2 and fig. 3 represents a micro step number of a stepping motor, an ordinate represents a set parameter, the set parameter may be, for example, a flow rate, and the micro step number of the stepping motor may represent a position of an electric valve, so that the curves shown in fig. 2 and fig. 3 may represent the set parameter curve, and include a corresponding relationship between a position of the electric valve and the set parameter.

As shown in fig. 2, under the constraints of the production process and assembly accuracy of mechanical structures such as the rotor and the stator of the stepping motor in the electric valve, and the influence of the magnetic field generated by the rotor in the stepping motor and the matching deviation between the rotor and the stator, the fluctuation of the actually measured set parameter curve has a certain periodicity, it should be noted that, the curve has a certain periodicity and does not limit the trend of the curve c1 to have a strict periodicity, the curve periodically appears convex and concave, i.e. the curve of the embodiment of the present invention periodically fluctuates, for example, the shape of the setting parameter curve in each area a is similar, fig. 3 is an enlarged schematic view of the setting parameter curve in one area a in fig. 2, the actually measured set parameter curve obtained in the following embodiments refers to an actually measured set parameter curve within one area a.

As shown in fig. 3, the actually measured set parameter curve includes a first curve segment from the first end point a to the second end point b and a second curve segment from the second end point b to the third end point c, where the first curve segment and the second curve segment may be partitions of the actually measured set parameter curve corresponding to a curve segment of the area a. For example, as shown in fig. 3, the difference of the setting parameters corresponding to one micro step of the stepping motor in the electric valve in the second curve segment may be set to be greater than 4% of the difference between the third setting parameter corresponding to the third endpoint c and the first setting parameter corresponding to the first endpoint a. Specifically, the third setting parameter corresponding to the third end point c is Lc, the first setting parameter corresponding to the first end point a is La, and the difference between the setting parameters corresponding to one micro step of the stepping motor in the electric valve in the second curve segment, that is, the difference between the vertical coordinates corresponding to two adjacent setting parameter points on the second curve segment needs to be greater than 4% of the difference between Lc and La, so as to improve the relative linearity of the second curve segment.

And S102, acquiring unit setting parameters according to the second curve segment.

And acquiring unit setting parameters according to the second curve segment. For example, the unit setting parameter may be obtained according to a second endpoint and a third endpoint on the second curve segment, where the unit setting parameter is a variation value of the setting parameter corresponding to one micro step of the stepping motor on the second curve segment, the unit setting parameter may be obtained according to a second position and the second setting parameter corresponding to the second endpoint and a third position and a third setting parameter corresponding to the third endpoint, a difference between the third position and the second position is a first difference, a difference between the third setting parameter and the second setting parameter is a second difference, and the unit setting parameter is equal to a ratio of the second difference to the first difference.

The second end point b may be set to have coordinates (Sb, Lb) and the third end point c may be set to have coordinates (Sc, Lc), and the unit setting parameter Pf satisfies the following calculation formula:

s103, obtaining interpolation setting parameter points according to the unit setting parameters and the first curve segment.

The interpolation setting parameter points are obtained according to the unit setting parameters and the first curve segment, and illustratively, the number of the interpolation setting parameter points to be inserted can be obtained according to the unit setting parameters and the first curve segment, and then the interpolation setting parameter points are obtained according to the unit setting parameters, the first curve segment and the number of the interpolation setting parameter points to be inserted.

For example, the number of the interpolation setting parameter points to be inserted may be obtained according to the unit setting parameter and the first curve segment, the number of the interpolation setting parameter points to be inserted may be obtained according to the second endpoint, the first endpoint and the unit setting parameter, for example, the number of the interpolation setting parameter points to be inserted may be obtained according to the first setting parameter corresponding to the second endpoint and the first endpoint and the unit setting parameter, a difference between the second setting parameter and the first setting parameter is a third difference, and the number of the interpolation setting parameter points to be inserted is equal to a ratio of the third difference to the unit setting parameter minus 1.

The coordinates of the first end point a may be (Sa, La), the coordinates of the second end point b may be (Sb, Lb), and the unit setting parameter Pf, the number n of interpolation setting parameter points to be inserted may satisfy the following calculation formula:

illustratively, the interpolation setting parameter points are obtained according to the unit setting parameters, the first curve segment and the number of the interpolation setting parameter points to be inserted, La +1 × pf, … …, La + n × pf are respectively used as the setting parameters corresponding to the interpolation setting parameter points, where La is the first setting parameter, n is the number of the interpolation setting parameter points to be inserted, n is a positive integer, pf is the unit setting parameter, La + n × pf is smaller than the second setting parameter corresponding to the second endpoint, and the setting parameter points on the first curve segment whose setting parameters are equal to the setting parameters corresponding to the interpolation setting parameter points are used as the interpolation setting parameter points.

For example, La may be equal to 2000mL/min, Lb may be equal to 2200mL/min, Lc may be equal to 4000mL/min, Sa may be equal to 100, Sb may be equal to 113, and Sc may be equal to 131, then it may be calculated according to the above calculation formula, Pf is equal to 100, n is equal to 1, that is, an interpolation setting parameter point needs to be inserted, then the setting parameter corresponding to the interpolation setting parameter point is La +1 × Pf is equal to 2100mL/min, it may be assumed that the abscissa of the setting parameter point d on the first curve segment whose setting parameter is equal to 2100mL/min is Sd, and Sd may be equal to Sa 8 plus 108, for example, then the setting parameter point with coordinates (108, 2100) may be used as the interpolation setting parameter point d.

It should be noted that, the number of interpolation setting parameter points to be inserted is only taken as 1 for example, and the number of interpolation setting parameter points to be inserted is not particularly limited in the embodiment of the present invention.

S104, inserting the interpolation setting parameter points into the first curve section, and taking the first endpoint, the interpolation setting parameter points and the second endpoint as the adjacent setting parameter points in sequence to enable the actually measured setting parameter curve to form a correction setting parameter curve.

The interpolation setting parameter points are inserted into the first curve section, the first end point, the interpolation setting parameter points and the second end point are used as the adjacent setting parameter points in sequence, and the difference of the positions of the electric valves corresponding to the adjacent parameter points can be set to correspond to one micro step of the stepping motor in the electric valve.

Fig. 4 is a schematic diagram of a modified setting parameter curve according to an embodiment of the present invention. As shown in fig. 4, the number of interpolation setting parameter points to be inserted may be set to 1, the first end point a and the interpolation setting parameter point d may be respectively used as a first setting parameter point and a second setting parameter point adjacent to each other on the correction setting parameter curve, the interpolation setting parameter point d and the second end point b may be respectively used as a second setting parameter point and a third setting parameter point adjacent to each other on the correction setting parameter curve, a difference between positions of the electrically operated valve corresponding to the first setting parameter point and the second setting parameter point corresponds to a microstep of the stepping motor in the electrically operated valve, and a difference between positions of the electrically operated valve corresponding to the second setting parameter point and the third setting parameter point corresponds to a microstep of the stepping motor in the electrically operated valve.

TABLE 1 correction of the relationship between the change in position of the front and rear electrically operated valves

Table 1 shows a relationship between changes in the position of the electrically operated valve before and after correction by using the control method provided in the embodiment of the present invention, and table 1 represents the position of the electrically operated valve by using the micro-step of the rotation of the stepping motor in the electrically operated valve. Referring to the above embodiment, La is equal to 2000mL/min, Lb is equal to 2200mL/min, Lc is equal to 4000mL/min, Sa is equal to 100, Sb is equal to 113, and Sc is equal to 131, corresponding to the actually measured set parameter curve, that is, before the interpolation set parameter point is not inserted, the flow rate of the stepping motor in the electric valve is changed from 2000mL/min to 2200mL/min and is rotated for 13 microsteps, and the flow rate of the stepping motor in the electric valve is changed from 2000mL/min to 4000mL/min and is rotated for 31 microsteps, corresponding to the set parameter curve before correction shown in fig. 3.

And correspondingly correcting the set parameter curve, namely after the interpolation set parameter point is inserted, calculating the coordinate of the obtained interpolation set parameter point d as (108, 2100), combining the first 8 microsteps from 0 to 7 into one microstep, combining the 5 microsteps from 8 to 12 into one microstep, and realizing that the first end point a, the interpolation set parameter point d and the second end point b are used as sequentially adjacent set parameter points on the correction set parameter curve, the difference of the positions of the electric valves corresponding to the adjacent set parameter points corresponds to one microstep of the stepping motor in the electric valve, namely the difference of the positions of the electric valves corresponding to the first end point a and the interpolation set parameter point d corresponds to one microstep of the stepping motor in the electric valve, and the difference of the positions of the electric valves corresponding to the interpolation set parameter point d and the second end point b corresponds to one microstep of the stepping motor in the electric valve. In addition, comparing fig. 3 and fig. 4, from the view point of curve change, the above operation is equivalent to that the actually measured set parameter curve before correction is from Sa to Sb, the stepping motor needs to rotate 13 microsteps, and the correction set curve is from Sa to Sb, the stepping motor only needs to rotate two microsteps, the point a position is not changed, the point b moves forward, that is, under the condition that the ordinate of the point b is not changed, the abscissa of the point b is reduced, and meanwhile, the point b moves forward to drive the second curve segment to keep the original shape and move forward as a whole. In this way, the difference in trend between the first and second curve segments is reduced, i.e. the trend of the first curve segment is closer to the trend of the second curve segment.

The method is applied to the complete set parameter curve with a plurality of fluctuation cycles shown in figure 2, so that each fluctuation cycle, namely the curve in each area A can be changed into the curve shape shown in figure 4, and the curve shown in figure 2 integrally moves forwards and upwards under the condition that the minimum flow value corresponding to the initial set parameter point and the maximum flow value corresponding to the final set parameter point are not changed, so that the actually measured set parameter curve forms a corrected set parameter curve, because the change trend of the first curve section is closer to the change trend of the second curve section in each area A, the fluctuation degree of the complete corrected set parameter curve relative to the actually measured set parameter curve is reduced, the operation of the electric valve is controlled according to the corrected set parameter curve, the uniformity degree of the set parameters of the electric valve is improved, and the problem of the fluctuation of the set parameters of the electric valve is improved, when the electric valve is an electronic expansion valve and the set parameter is flow, the problem of flow fluctuation can be improved.

And S105, controlling the operation of the electric valve according to the corrected set parameter curve.

The method includes the steps of controlling the operation of the electric valve according to a corrected set parameter curve, for example, controlling the operation of the electric valve to conform to the corrected set parameter curve, and exemplarily, obtaining a target driving current required by driving a stepping motor in the electric valve according to a change rule of a set parameter corresponding to each set parameter point on the corrected set parameter curve, and adjusting the driving current output to the stepping motor to the target driving current so that the change of the set parameter corresponding to the electric valve conforms to the change rule of the corrected set parameter curve. Therefore, the electric valve operation is controlled according to the corrected setting curve, so that the uniformity degree of the setting parameters of the electric valve is improved, the problem of the fluctuation of the setting parameters of the electric valve is solved, and when the electric valve is an electronic expansion valve and the setting parameters are flow, the problem of the fluctuation of the flow can be solved.

Fig. 5 is a flowchart illustrating a second control method according to an embodiment of the present invention. On the basis of the control method shown in fig. 1, before the set parameter curve of the actual measurement is obtained, the set parameter calibration interval may also be obtained according to whether a calibration instruction is received, and accordingly, obtaining the set parameter curve of the actual measurement includes obtaining the set parameter curve of the actual measurement corresponding to the set parameter calibration interval. As shown in fig. 5, the control method includes:

s201, acquiring a set parameter calibration interval according to whether a calibration instruction is received.

Before the set parameter curve of actual measurement is obtained, the set parameter calibration interval can be obtained according to whether a calibration instruction is received or not. For example, the set parameter calibration interval may be set to correspond to a stage from the start of the operation of the electric valve to the time when the flow rate corresponding to the electric valve is 3% of the maximum flow rate, and since the electric valve has a set parameter in a small opening range, for example, in 15 whole steps after the occurrence of the valve opening pulse, for example, the fluctuation of the flow rate is large, the set parameter calibration interval may be set to correspond to the small opening range of the electric valve, for example, the set parameter calibration interval may be set to correspond to 15 whole steps after the occurrence of the valve opening pulse.

S202, acquiring a set parameter curve of actual measurement corresponding to a set parameter calibration interval; the setting parameter curve comprises a corresponding relation between the position of the electric valve and the setting parameter, and the setting parameter curve comprises a first curve section from a first endpoint to a second endpoint and a second curve section from the second endpoint to a third endpoint.

The set parameter curve of actual measurement can be obtained by obtaining the set parameter curve of actual measurement corresponding to the set parameter calibration interval, and similarly, the electric valve can be set to comprise an electronic expansion valve comprising a valve core, the set parameter comprises flow, and the set parameter curve comprises the corresponding relation between the position of the valve core and the flow.

In an exemplary embodiment, the electronic expansion valve may further include a motor, the setting parameter may further include a micro-step value of the motor, the position of the valve element is determined by the micro-step value of the motor, the setting parameter curve further includes a corresponding relationship between the micro-step value of the motor and a flow rate, and the operation of the electronic expansion valve conforms to the corrected setting parameter curve by adjusting the micro-step value of the motor.

And S203, acquiring unit setting parameters according to the second curve segment.

And S204, obtaining interpolation setting parameter points according to the unit setting parameters and the first curve segment.

S205, the interpolation setting parameter points are inserted into the first curve segment, and the first end point, the interpolation setting parameter points and the second end point are used as the adjacent setting parameter points in sequence, so that the actually measured setting parameter curve forms a correction setting parameter curve.

And S206, controlling the electric valve to operate according to the corrected set parameter curve.

Before the set parameter curve of actual measurement is obtained, the set parameter calibration interval is obtained according to whether a calibration instruction is received or not, and then the set parameter curve of actual measurement corresponding to the set parameter calibration interval is obtained, namely, the set parameter curve in the set parameter calibration interval needing to be adjusted is only corrected, so that the efficiency of correcting the set parameter curve is improved.

Fig. 6 is a flowchart illustrating a third control method according to an embodiment of the present invention. The control method can be applied to a scene needing to control the electric valve, and can be executed by a control system of the electric valve, and the control system can be executed in a software and/or hardware mode. As shown in fig. 6, the control method includes:

s301, acquiring a set parameter curve of actual measurement; the setting parameter curve comprises the corresponding relation between the position of the electric valve and the setting parameter.

And acquiring a set parameter curve of actual measurement, wherein the set parameter curve comprises the corresponding relation between the position of the electric valve and the set parameter. For example, the electric valve may include an electronic expansion valve including a valve core, the setting parameter includes a flow rate, and the setting parameter curve includes a corresponding relationship between a position of the valve core and the flow rate. The position of the electric valve can be understood as the position of a valve core of the electric valve, and the position of the valve core of the electric valve, the opening area of a valve port of the electric valve and the micro-step number of the stepping motor are all in a linear relation, so that the position of the electric valve can be represented by the micro-step number of the stepping motor in the electric valve.

Fig. 7 is a schematic diagram of a set parameter curve according to an embodiment of the present invention. As shown in fig. 7, the abscissa represents the number of micro steps of the stepping motor, the ordinate represents the setting parameter, the setting parameter may be, for example, the flow rate, and the number of micro steps of the stepping motor may represent the position of the electric valve, so the curve shown in fig. 7 may represent the setting parameter curve, including the corresponding relationship between the position of the electric valve and the setting parameter, and the curve c1 in fig. 7 is the actually measured setting parameter curve, and it can be seen that the actually measured setting parameter curve c1 has large fluctuation and unsmooth curve as a whole.

S302, acquiring reference setting parameters according to a setting parameter curve of actual measurement; wherein, the reference setting parameter is equal to a% of the ratio of the total setting parameter corresponding to the actually measured setting parameter curve to the position variation value of the electric valve.

Acquiring reference setting parameters according to a setting parameter curve actually measured; wherein, the reference setting parameter is equal to a% of the ratio of the total setting parameter corresponding to the actually measured setting parameter curve to the position variation value of the electric valve.

For example, the total flow rate may be L, that is, the difference between the ordinate corresponding to the end point setting parameter point and the ordinate corresponding to the start point setting parameter point on the curve c1 is L, the position variation value of the electrically operated valve corresponding to the actually measured setting parameter curve is a, that is, the number of microsteps from the start point setting parameter point to the end point setting parameter point in fig. 7 is a, that is, the difference between the abscissa corresponding to the end point setting parameter point and the abscissa corresponding to the start point setting parameter point on the curve c1 is a, and a% of the ratio of L to a is the reference setting parameter Δ L. Illustratively, a% is 6% or more and 14% or less.

And S303, deleting part of setting parameter points on the actually measured setting parameter curve according to the reference setting parameter to form a corrected setting parameter curve.

After the reference setting parameter Δ L is determined, a correction setting parameter curve may be formed by deleting a part of the setting parameter points on the actually measured setting parameter curve according to the reference setting parameter. Specifically, the difference between the vertical coordinates corresponding to every two adjacent set parameter points on the actually measured set parameter curve c1 may be obtained, and the correction set parameter curve may be formed by deleting the set parameter point on the actually measured set parameter curve c1 where the difference between the vertical coordinate corresponding to the previous adjacent set parameter point and the vertical coordinate corresponding to the previous adjacent set parameter point is smaller than the reference set parameter Δ L, as shown by a curve c2 in fig. 7, it can be seen that the linearity of the correction set parameter curve c2 is obviously improved and the fluctuation of the set parameter is reduced compared with the actually measured set parameter curve c1 before the correction.

And S304, controlling the operation of the electric valve according to the corrected set parameter curve.

The electric valve is controlled to operate according to the corrected set parameter curve, for example, the target driving current required by the stepping motor in the electric valve can be obtained according to the change rule of the set parameter corresponding to each micro-step point on the corrected set parameter curve, and the driving current output to the stepping motor is adjusted to the target driving current, so that the change rule of the set parameter curve is corrected in a compounding manner according to the change of the set parameter corresponding to the electric valve. Therefore, the uniform change of the set parameters of the electric valve is facilitated, the linearity of the set parameter curve is improved, and the problem of fluctuation of the set parameters is solved.

The embodiment of the invention also provides a control system which can control the electric valve. Fig. 8 is a schematic block diagram of a first control system according to an embodiment of the present invention, as shown in fig. 8, the control system includes an actual curve obtaining module 401, a unit parameter obtaining module 402, an interpolation parameter point obtaining module 403, a correction curve obtaining module 404, and an electric valve control module 405, the actual curve obtaining module 401 is configured to obtain a set parameter curve of actual measurement, the set parameter curve includes a corresponding relationship between a position of an electric valve and a set parameter, the set parameter curve includes a first curve segment from a first endpoint to a second endpoint and a second curve segment from the second endpoint to a third endpoint, the unit parameter obtaining module 402 is configured to obtain the unit set parameter according to the second curve segment, the interpolation parameter point obtaining module 403 is configured to obtain an interpolation set parameter point according to the unit set parameter and the first curve segment, the correction curve obtaining module 404 is configured to insert the interpolation set parameter point into the first curve segment, and the first end point, the interpolation setting parameter point and the second end point are taken as the adjacent setting parameter points in sequence so that the actually measured setting parameter curve forms a correction setting parameter curve, and the electric valve control module 405 is used for controlling the electric valve to operate according to the correction setting parameter curve.

The control system provided by the embodiment of the invention can also enable the fluctuation degree of the formed correction setting parameter curve relative to the actually measured setting parameter curve to be reduced by inserting the interpolation setting parameter point into the first curve section and taking the first endpoint, the interpolation setting parameter point and the second endpoint as the adjacent setting parameter points in sequence, and control the operation of the electric valve according to the correction setting parameter curve is beneficial to improving the uniformity degree of the setting parameter of the electric valve and improving the problem of the fluctuation of the setting parameter of the electric valve. The embodiment of the invention also provides an electric valve, and fig. 9 is a schematic structural view of the electric valve provided by the embodiment of the invention. As shown in fig. 9, the electric valve 100 includes a housing 60, a stator assembly 601, a rotor assembly 602, a valve core 603, and a circuit board assembly 90, the circuit board assembly 90 is disposed in an inner cavity formed by the housing 60, the stator assembly 601 is disposed at an outer periphery of the rotor assembly 602, the rotor assembly 602 and the stator assembly 601 form a stepping motor in the electric valve 100, the stator assembly 601 includes a coil, the rotor assembly 602 includes a permanent magnet, the coil is electrically connected to the circuit board assembly 90, the coil generates an excitation magnetic field after being energized, the rotor assembly 602 operates in the excitation magnetic field, the stepping motor drives the valve core 603 of the electric valve to move relative to the valve port 604, so that the valve port 604 reaches a corresponding opening degree, the position of the valve core 603 is a position of the electric valve, and. The control system of the above embodiment is integrated in the circuit board assembly, so that the control system also has the beneficial effects of the above embodiment, and details are not described here.

A fourth embodiment of a control method for controlling an electrically operated valve, the control method comprising controlling the operation of the electrically operated valve to conform to a revised set parameter curve; the correction setting parameter curve is prestored in a control system for controlling the operation of the electric valve, the correction setting parameter curve changes along with the change of the setting parameter curve, the setting parameter curve comprises the corresponding relation between the position of the electric valve and the setting parameter, and the setting parameter curve comprises a first curve section from a first end point to a second end point and a second curve section from the second end point to a third end point; the correction setting parameter curve is obtained by obtaining a unit setting parameter according to the second curve segment, obtaining an interpolation setting parameter point according to the unit setting parameter and the first curve segment, inserting the interpolation setting parameter point into the first curve segment, and taking the first endpoint, the interpolation setting parameter point and the second endpoint as the adjacent setting parameter points in sequence.

The fourth control method embodiment differs from the first, second and third control method embodiments mainly in that: the correction setting parameter curve is prestored in a control system for controlling the electric valve, the correction setting parameter curve changes along with the change of the setting parameter curve, and under the condition that the setting parameter curve is not changed, the acquisition process of the correction setting parameter curve is not required, so that the batch production is facilitated. The control method is thus simpler and the control system requires less space, wherein the set parameter curve can be corrected either on-line or off-line if it changes, wherein the on-line correction is the same as in the first, second and third embodiments of the control method and the off-line correction is the same as in the fourth embodiment.

The embodiment of the invention also provides a second control system which can control the electric valve and comprises an electric valve control module and a storage module, wherein the electric valve control module is used for controlling the operation of the electric valve to accord with the corrected set parameter curve; the storage module stores a correction setting parameter curve, the correction setting parameter curve changes along with the change of the setting parameter curve, the setting parameter curve comprises the corresponding relation between the position of the electric valve and the setting parameter, and the setting parameter curve comprises a first curve section from a first end point to a second end point and a second curve section from the second end point to a third end point; the correction setting parameter curve is obtained by obtaining a unit setting parameter according to the second curve segment, obtaining an interpolation setting parameter point according to the unit setting parameter and the first curve segment, inserting the interpolation setting parameter point into the first curve segment, and taking the first endpoint, the interpolation setting parameter point and the second endpoint as the adjacent setting parameter points in sequence.

The main differences between the embodiment of the second control system compared to the embodiment of the first control system are: under the condition that the set parameter curve is not changed, the acquisition process of correcting the set parameter curve is not needed, namely, the actual curve acquisition module 401, the unit parameter acquisition module 402, the interpolation parameter point acquisition module 403, the correction curve acquisition module 404, the storage module for setting the correction set parameter curve are not needed for storing the correction set parameter curve, and if the set parameter curve is not changed, the change of the correction set parameter curve is not needed, so that the batch production is facilitated. Wherein if the set parameter curve changes, the modification of the corrected set parameter curve can be performed on-line or off-line, wherein the on-line correction process is the same as the implementation of the first control system, and wherein the off-line correction process is the same as the implementation of the second control system.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments illustrated herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.