A method for controlling the opening degree of an intelligent control valve

Abstract

The application provides a kind of intelligent control valve opening degree control method, comprising the following steps: step one: obtaining target temperature T 目 And according to target temperature T 目 , judge valve A reaches the preset opening degree A 预 Of valve at target temperature;Step two: by two-way AD sampling, respectively in the full open and full close state of valve cross sampling, obtain four sampling voltage values;Step three: by four sampling voltage values and AVCC calculate the total resistance value R3+R4 that potentiometer participates in in the full open and full close state of valve;Step four: by control device control valve movement, so that opening and closing resistance value is equal to (R3+R4) * A 预 ;The application is convenient for accurately determining valve position, improves the precision of control valve movement.

Description

Technical Field

[0001] This invention relates to the field of valve control technology, specifically to a method for controlling the opening degree of an intelligent control valve. Background Technology

[0002] In the heating industry, traditional ball valves only function as on / off switches. For example, if a user reports a heating outage, the valve is completely shut off. However, for ordinary heating users, the valve is usually fully open. With all residential heating ball valves fully open, this often results in different water pressures for residents on different floors of a building. Lower-floor residents have higher water pressure and a larger flow rate for heating, while higher-floor residents have lower water pressure and a smaller flow rate, leading to different heating temperatures for residents on different floors.

[0003] Therefore, automatically adjusting valve opening by comparing inlet and outlet water temperatures is a current technological trend. However, most current valve control relies on human intervention, increasing unnecessary labor costs. Precise valve opening control is crucial for achieving arbitrary valve opening. Traditional valve positioning detection initially relied on a stall mechanism, where a sudden increase and maintenance of current was detected by assessing the current. Later, limit switches were added to both sides of the valve to determine positioning. While these methods satisfy normal valve opening / closing criteria, arbitrarily controlling valve opening is extremely difficult. To roughly control valve opening, the switching time is recorded for each valve model. Since the valve moves at a constant speed during operation, the total time can be used to approximate the valve opening. However, these existing control methods offer low precision in controlling intelligent valve opening and are not suitable for accurately determining valve position. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides an intelligent control valve opening control method, which facilitates accurate determination of the valve position and improves the precision of valve movement control.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a method for controlling the opening degree of an intelligent control valve, comprising the following steps:

[0006] Step 1: Obtain the target temperature T 目 And based on the target temperature T 目 Determine the preset opening degree A of valve A when it reaches the target temperature. 预 ;

[0007] Step 2: Using two-channel AD sampling, cross-sample the voltage values ​​when the valve is fully open and fully closed, respectively, to obtain four sampled voltage values;

[0008] Step 3: Calculate the total resistance value R3+R4 of the potentiometer in the fully open and fully closed states of the valve using the four sampled voltage values ​​and AVCC.

[0009] When the valve is fully open, with PB14 as the sampling point, PB15 outputs high, the voltage of PB14 is AD1, and the total voltage is AVCC1; at this time, with PB15 as the sampling point, PB14 outputs high, the voltage of PB14 is AD2, and the total voltage is AVCC2.

[0010] When the valve is fully closed, PB15 is the sampling point, PB14 outputs high, the voltage of PB14 is AD3, and the total voltage is AVCC3; at this time, PB14 is the sampling point, PB15 outputs high, the voltage of PB14 is AD4, and the total voltage is AVCC4.

[0011] Step 4: Control the valve's movement using the control device, ensuring the opening and closing resistance equals (R3 + R4) * A. 预 ;

[0012] In step three, the four sampled voltage values ​​are input into the four formulas (1) to (4) to obtain the values ​​of R2, R3+R4, and R5;

[0013]

[0014] R1 and R6 are 10K resistance values; the movement of the endpoint of R6 on the potentiometer is assumed to be from the top of resistor R3 to the bottom of resistor R4, and the entire R3+R4 is the resistance range when the valve is open and closed; R2+R+R5 is the resistance range of the entire potentiometer, and the values ​​of R2, R3+R4, and R5 are obtained by calculation.

[0015] Preferably, the steps for adjusting the valve opening using a control device are as follows:

[0016] Obtain the target temperature T 目 and actual ambient temperature T 实 And compare the target temperature T 目 and actual ambient temperature T 实 ;

[0017] If the target temperature T 目 Greater than the actual ambient temperature T 实 Then calculate the target temperature T. 目 Compared with the actual ambient temperature T 实 The temperature difference is obtained, and the temperature difference value is compared with the preset temperature difference threshold. When the temperature difference value is greater than the preset temperature difference threshold, the opening adjustment direction is marked as opening larger, and the valve opening is increased by adjusting the adjustment device.

[0018] If the target temperature T 目 Less than the actual ambient temperature T实 Then calculate the temperature difference between the current ambient temperature and the target temperature, and compare the temperature difference value with the preset temperature difference threshold. When the temperature difference value is greater than the preset temperature difference threshold, mark the opening adjustment direction as closing, and adjust the valve opening to decrease through the adjustment device.

[0019] If the target temperature T 目 Equal to the actual ambient temperature T 实 The valve opening direction is marked as none, and the valve opening remains unchanged.

[0020] Preferably, the control device uses a DC motor to drive the control valve to open and close.

[0021] The beneficial effects of this invention are as follows: A potentiometer detects the voltage value of the valve in both fully open and fully closed states, and the sum of the corresponding resistance values ​​of the potentiometer in the fully open and fully closed states is obtained from these voltage values. A control device then controls the valve's movement, ensuring that the opening and closing resistance is equal to (R3 + R4) * A. 预 This facilitates real-time and precise adjustment of the valve opening, enabling automatic control of inlet and outlet water temperatures, improving the accuracy of valve movement control, and preventing the valve opening judgment result from being affected by the power supply voltage. Attached Figure Description

[0022] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention, but do not constitute a limitation thereof. In the drawings:

[0023] Figure 1 This is a schematic diagram of the opening control method for the intelligent control valve proposed in this invention.

[0024] Figure 2 This is a schematic diagram of the potentiometer and its equivalent structure according to the present invention. Detailed Implementation

[0025] To make the technical means, creative features, achieved objectives, and effects of this invention readily understandable, the invention is further described below with reference to specific embodiments and accompanying drawings. However, the following embodiments are merely preferred embodiments of this invention and not all embodiments. Other embodiments obtained by those skilled in the art based on the embodiments described herein without creative effort are all within the protection scope of this invention.

[0026] Please see Figure 1-2 As shown, a method for controlling the opening degree of an intelligent control valve includes the following steps:

[0027] Step 1: Obtain the target temperature T 目 And based on the target temperature T目 Determine the preset opening degree A of valve A when it reaches the target temperature. 预 ;

[0028] Step 2: Using two-channel AD sampling, cross-sample the voltage values ​​when the valve is fully open and fully closed, respectively, to obtain four sampled voltage values;

[0029] Step 3: Calculate the total resistance value R3+R4 of the potentiometer in the fully open and fully closed states of the valve using the four sampled voltage values ​​and AVCC.

[0030] Step 4: Control the valve's movement using the control device, ensuring the opening and closing resistance equals (R3 + R4) * A. 预 .

[0031] like Figure 2 As shown, the resistance values ​​of the potentiometer when it is open and closed are calculated through these two channels. Then, the resistance value is used to determine the opening degree, which is not affected by the power supply voltage. This makes it easier to accurately determine the valve position and improves the precision of valve movement control. By judging the valve opening degree through the resistance value, the judgment result is avoided from being affected by the power supply voltage. The valve movement is directly adjusted by the control device, and the valve position can be precisely controlled and adjusted by controlling the opening and closing resistance value.

[0032] The existing method for controlling the valve opening degree is as follows: first, perform the valve opening and closing movement, record the opening and closing time, and determine the opening degree based on the ratio of the running time to the total time.

[0033] The current valve opening control method is as follows: Figure 2 As shown in the two diagrams, R1 and R6 are known 10K resistance values. The potentiometer in the left diagram is equivalent to R2 / R3 / R4 / R5 in the right diagram. The movement of the endpoint of R6 on the potentiometer will not be exactly at both ends (the top of R2 and the bottom of R5). Therefore, we assume the maximum upward movement of the endpoint of R6 is to the top of resistor R3, and the maximum downward movement is to the bottom of resistor R4. The entire R3+R4 represents the resistance range when the valve is open and closed, which we denote as R. R2+R+R5 represents the entire resistance range of the potentiometer.

[0034] like Figure 2 As shown, with vertex R3 fully open and bottom point R4 fully closed, by connecting the two endpoints to high and sampling respectively, the following formula can be obtained:

[0035]

[0036] Given R1 and R6, the values ​​of R2, R3+R4, and R5 can be calculated. Then, based on the resistance ratio, the corresponding sampled values ​​are obtained to determine the current potentiometer position.

[0037] The origin of the formulas can be illustrated by the first formula:

[0038] With the top of R3 representing a fully open valve and the bottom of R4 representing a fully closed valve, assuming that when the valve reaches the top of R3, PB14 is the sampling point and PB15 outputs high, according to the series voltage divider, we can obtain formula (1). The voltage of PB14 is AD1, and the total voltage is AVCC1. If PB15 is the sampling point and PB14 outputs high, we can similarly obtain formula (2).

[0039] Assuming the valve reaches the bottom of R4, formulas (3) and (4) can be obtained similarly. The voltage of AVCC is basically the same. By combining these formulas, we can obtain R2, R = R3 + R4, R5. When the valve is running dynamically, assuming the opening is 20%, the resistance value is equal to (R3 + R4) * 20%, which is the opening we want.

[0040] Specifically, two potentiometers are used to detect the voltage values ​​of the control valve in the fully open and fully closed states, respectively; and a potentiometer is used to detect the voltage value U across the control valve in its actual state. 工 The valve opening degree A is determined by the voltage value across the valve under actual conditions; the valve opening degree A is then controlled by the control device to the predetermined opening degree A. 预 The opening degree A of the control valve is verified by using a potentiometer.

[0041] This method can also be used to achieve precise control of valves.

[0042] like Figure 1-2 As shown, the key to intelligent valves lies in their arbitrary opening degree. To achieve this, potentiometers are added to both ends of the valve. Determining the valve position through these potentiometers is convenient and accurate. In actual valve applications, only a small portion of the potentiometer's resistance may participate in the entire valve opening and closing process. Therefore, an initial test is necessary to detect the voltage values ​​corresponding to the opening and closing of the valve when the potentiometer is involved. The opening voltage value lies between these two voltage values. By sampling the relatively real-time voltage value, the current valve opening degree is determined. Verifying the valve opening degree through the potentiometer ensures the correctness and accuracy of the valve position, guaranteeing precise valve control.

[0043] While this technical solution is feasible compared to determining the valve position through resistance values, if powered by a battery, the voltage will inevitably change over time. This may not be noticeable in the short term, but as time goes on, if the positions at both ends are not frequently sampled and corrected, the valve will become increasingly inaccurate because the power supply voltage affects the sampling voltage.

[0044] One method to determine the valve position (valve opening) is by measuring the voltage across the valve terminals, which can be compared with the method of measuring the valve position by measuring the resistance value. This helps to ensure the accuracy of the valve's movement.

[0045] Actual valve opening A 实 and preset opening A 预 The steps for adjusting the valve opening using the control device are as follows:

[0046] Obtain the target temperature T 目 and actual ambient temperature T 实 And compare the target temperature T 目 and actual ambient temperature T 实 ;

[0047] If the target temperature T 目 Greater than the actual ambient temperature T 实 Then calculate the target temperature T. 目 Compared with the actual ambient temperature T 实 The temperature difference is obtained, and the temperature difference value is compared with the preset temperature difference threshold. When the temperature difference value is greater than the preset temperature difference threshold, the opening adjustment direction is marked as opening larger, and the valve opening is increased by adjusting the adjustment device.

[0048] If the target temperature T 目 Less than the actual ambient temperature T 实 Then calculate the temperature difference between the current ambient temperature and the target temperature, and compare the temperature difference value with the preset temperature difference threshold. When the temperature difference value is greater than the preset temperature difference threshold, mark the opening adjustment direction as closing, and adjust the valve opening to decrease through the adjustment device.

[0049] If the target temperature T 目 Equal to the actual ambient temperature T 实 The valve opening direction is marked as none, and the valve opening remains unchanged.

[0050] The control device uses a DC motor to drive the control valve to open and close.

[0051] The target temperature is the temperature of the liquid flowing through the valve as set by the user, while the actual ambient temperature refers to the actual temperature outside the valve.

[0052] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method of controlling the opening degree of an intelligent control valve, characterized by, Comprising the following steps: Step one: Obtain target temperature T 目 And according to target temperature T 目 , determine the preset opening A of valve A when valve A reaches target temperature 预 ; Step two: through two-way AD sampling, respectively in the valve full open and full closed state cross sampling, get four sampling voltage values; Step three: through four sampling voltage values and AVCC calculate the total resistance value R3+R4 of the potentiometer in the valve full open and full closed state; Valve full open, PB14 as the sampling point, PB15 output high, PB14 voltage is AD1, the total voltage is AVCC1; At this time, PB15 as the sampling point, PB14 output high, PB14 voltage is AD2, the total voltage is AVCC2; Valve full closed, PB15 as the sampling point, PB14 output high, PB14 voltage is AD3, the total voltage is AVCC3; At this time, PB14 as the sampling point, PB15 output high, PB14 voltage is AD4, the total voltage is AVCC4; Step four: control the valve to move by the control device, so that the opening and closing resistance value is equal to (R3+R4)*A 预 ; Step three will be obtained four sampling voltage values input (1) to (4) four formulas, get R2, R3+R4, R5 value; Where R1 and R6 are 10K resistance; R6 endpoint on the potentiometer movement, R6 endpoint movement range is assumed to be up to the top of R3 resistance, down to the bottom of R4 resistance, the whole R3+R4 for the valve opening and closing resistance range; R2+R+R5 is the resistance range of the whole potentiometer, through the calculation of R2, R3+R4, R5 value.

2. The method of claim 1, wherein: Through the control device to adjust the valve opening steps as follows: acquire a target temperature T 目 and the actual ambient temperature T 实 , and compare the target temperature T 目 and the actual ambient temperature T 实 ; If the target temperature T 目 Greater than the actual ambient temperature T 实 Then calculate the target temperature T. 目 Compared with the actual ambient temperature T 实 The temperature difference is obtained, and the temperature difference value is compared with the preset temperature difference threshold. When the temperature difference value is greater than the preset temperature difference threshold, the opening adjustment direction is marked as opening larger, and the valve opening is increased by adjusting the adjustment device. If the target temperature T 目 is less than the actual ambient temperature T 实 , the temperature difference between the current ambient temperature and the target temperature is recalculated, and the temperature difference value is compared with the preset temperature difference threshold value. When the temperature difference value is greater than the preset temperature difference threshold value, the opening adjustment direction is marked as closing small, and the valve opening is adjusted to be smaller by the adjusting device. If the target temperature T 目 is equal to the actual ambient temperature T 实 , the flag opening adjustment direction is null, and the valve opening is maintained as is.

3. The method of claim 1, wherein: The control device uses a DC motor, through the DC motor drive control valve valve opening and closing movement.

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