Electric contact water level measurement method and system based on double sliding window detection

Abstract

The application discloses a kind of electric contact water level measurement method and system based on double sliding window detection, for the problem that traditional electric contact water level detection method is easy to fail after scaling, double sliding window detection electric contact water level measurement method is proposed to detect the resistance change of electric contact water level gauge probe, the method provided in the embodiment selects the energy ratio in double sliding window as decision variable, by comparing decision variable with the set two threshold values, to monitor the immersion condition of electric contact water level probe;The resistance change of electric contact water level gauge probe is comprehensively considered in a period of time, so that the decision variable of water level judgment is more significant, more reasonable than traditional determination method, and the service life of electric contact probe after scaling can be effectively prolonged.

Description

Technical Field

[0001] This application relates to the field of industrial measurement technology, specifically to a method and system for measuring electrical contact water level based on dual sliding window detection. Background Technology

[0002] Electrical contact level measurement technology is one of the commonly used level measurement technologies in automated production. It features simple structure, convenient installation, and high reliability, and is widely used in level measurement in boiler drums, deaerators, heaters, evaporators, and other applications. An electrical contact level gauge is a discontinuous level measurement device. Between the two electrodes at the probe of the electrical contact level gauge is a section of insulator with a high resistance. The basic working principle of the electrical contact level gauge is based on the significant difference in conductivity between water, air, or water vapor. It determines whether the electrodes are submerged by measuring the equivalent resistance between the electrodes and comparing it to a preset threshold. The electrical contact level gauge is installed on the side of the container being measured via a measuring cylinder, connected to the upper and lower ends of the container. When the corresponding electrical contact level gauge is submerged in water, the insulator surface between the two electrodes is coated with a low-resistance working fluid, resulting in a low-resistance state between the two electrodes; when the electrical contact level gauge is not submerged, the two electrodes exhibit a high-resistance state. By measuring the impedance state between the two electrodes in real time and comparing it with the set impedance threshold, it is possible to determine whether the electric contact level gauge is submerged in water, thereby detecting the water level height inside the measuring cylinder.

[0003] However, electric contact level gauges typically operate within the measuring cylinder of the container being measured. The working fluid in this cylinder contains strong base-weak acid salts such as phosphates, hydrogen phosphates, and sulfites, resulting in an overall alkaline water quality and high electrolyte content. Under conditions of immersion in liquid and prolonged energization, corrosion and scaling inevitably occur on the electric contact probe. Chemical testing reveals that the scale adhering to the probe surface contains a large amount of metal oxides, which reduces the probe's equivalent resistance. Consequently, the equivalent resistance of the electric contact probe decreases continuously with increasing usage time. Currently, the engineering method for measuring electric contact level is still a simple fixed threshold detection method. This involves comparing the equivalent resistance of the electric contact probe with a set threshold to determine whether the probe is in contact with water. For example, the equivalent resistance of the electric contact level probe when in contact with water is around 100KΩ, while the equivalent resistance when not in contact with water is approximately 100MΩ. Considering the possibility of residual water film on the electric contact probe, the detection threshold is usually set to 1MΩ. When the equivalent resistance of the electric contact water level probe decreases continuously due to scaling, it exhibits a low impedance state when the working fluid being measured does not submerge the electric contact water level gauge. Traditional electric contact water level determination methods are prone to failure, and the probe will be considered as a short circuit and needs to be replaced. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, this application provides a method and system for measuring the water level of electrical contacts based on dual sliding window detection. The ratio of energy within the dual sliding window is used as a decision variable, and the immersion status of the electrical contact water level probe is monitored by comparing the decision variable with two set thresholds.

[0005] This invention provides a method for measuring water level at electrical contacts based on dual sliding window detection, comprising the following steps:

[0006] S1. Continuously measure the equivalent resistance of the electrical contact level gauge located inside the measuring cylinder;

[0007] S2. The equivalent resistance of the continuously recorded electrical contact level gauge is used as the input signal of the detection module. The output signal passes through two continuous sliding windows A and B, and the energy a of sliding window A and sliding window B is calculated respectively. n and b n and the judgment variable m n ;

[0008] S3. Determine the value of the switch signal S0, wherein the initial value of the switch signal S0 is 0;

[0009] S4. If the switch signal S0 is 0, then continue to detect the decision variable m. n If the decision variable m n If the water level is less than the probe's water contact threshold H1, then the switch signal S0 outputs S0 = 1; otherwise, it outputs S0 = 0. If the switch signal S0 is 1, then the decision variable m continues to be detected. n If the decision variable m n If the value is greater than the probe's water outlet threshold H2, then the switch signal S0 outputs S0 = 0; otherwise, it outputs S0 = 1.

[0010] S5. Output the result, update and register the current switch signal S0, and return to step S3;

[0011] Among them, a n and b n This represents the cumulative sum of the current input resistance value over the window length, and the decision variable m n The ratio of the energy of the two sliding windows; S0 = 1, which means the electric contact level gauge probe is submerged in water; S0 = 0, which means the electric contact level gauge probe is not submerged in water.

[0012] According to the embodiment of the present invention, in the method for measuring electrical contact water level based on dual sliding window detection, in step S1, the power supply module applies a voltage signal to the two poles of the electrical contact water level gauge, and simultaneously measures the current signal of the two poles of the electrical contact water level gauge, calculates the equivalent resistance of the electrical contact water level gauge, and forms a real-time resistance measurement curve.

[0013] According to the embodiment of the present invention, in the method for measuring electrical contact water level based on dual sliding window detection, in step S2, the length of the sliding window A is M and the length of the sliding window B is L; wherein the length M of the sliding window A is equal to the length L of the sliding window B, and the sliding window A and the sliding window B are relatively stationary when sliding to the right.

[0014] According to the embodiment of the present invention, in the method for measuring electrical contact water level based on dual sliding window detection, in step S2, the energy a of the sliding window A is... n for:

[0015]

[0016] Where, r n To calculate the nth equivalent resistance value, M is the length of the sliding window A, and a n This is the cumulative sum of the current input resistance value data over the length of the sliding window A.

[0017] According to the embodiment of the present invention, in the method for measuring electrical contact water level based on dual sliding window detection, in step S2, the energy b of the sliding window A is... n for:

[0018]

[0019] Where, r n To calculate the nth equivalent resistance value, L is the length of the sliding window B, and b n This is the cumulative sum of the current input resistance value data over the length of the sliding window B.

[0020] According to the embodiment of the present invention, in the method for measuring electrical contact water level based on dual sliding window detection, in step S2, the decision variable m n for:

[0021] According to the embodiment of the present invention, in the method for measuring electrical contact water level based on dual sliding window detection, in step S4, when the electrical contact water level gauge is not in contact with water, the equivalent resistance of the electrical contact water level gauge is in a high-resistance state, and the cumulative sum of the resistance values ​​in sliding window A and sliding window B is a. n and b n Similarly, the decision variable m n It is in a flat state.

[0022] According to the embodiment of the present invention, in the method for measuring electrical contact water level based on dual sliding window detection, in step S4, when the electrical contact water level gauge comes into contact with water, the equivalent resistance of the electrical contact water level gauge is low, and the input signal of the detection module shows a falling edge. When the falling edge of the data reaches the sliding window A, the energy a of the sliding window A is... n The resistance will be reduced until the data contained in the sliding window A are all low resistance values, while the energy b of the sliding window B... n When the resistance is high, the decision variable m... n It reaches its lowest value; then the sliding window B begins to show a falling edge, and the decision variable m n The value begins to increase. When the data contained in the sliding window B are all low-resistance values, the decision variable m... n It is in a flat state.

[0023] According to the embodiment of the present invention, in the method for measuring electrical contact water level based on dual sliding window detection, in step S4: when the decision variable m n When the water level is less than the probe's water contact threshold H1, it indicates a rising water level, and the electrical contact water level gauge is submerged; when the decision variable m n When the water level is greater than the probe's water outlet threshold H2, it indicates that the water level has dropped and the electrical contact water level gauge is above the water level.

[0024] This invention also provides a dual-sliding-window detection electrical contact water level measurement system, the dual-sliding-window detection electrical contact water level measurement system comprising:

[0025] A measuring cylinder connected to the container being measured;

[0026] An electrical contact level gauge distributed inside the measuring cylinder for measuring the water level height of the sampled water column;

[0027] The power module connected to the electric contact level gauge is used to provide power to the electric contact level measurement system with dual sliding window detection.

[0028] A microcontroller connecting the electrical contact water level gauge and the power module, the microcontroller including a resistance measurement module, a water level detection module and an output module;

[0029] The measuring resistance module measures the equivalent resistance of the electrical contact level gauge in real time, the detecting level module detects the water level in real time based on the equivalent resistance of the electrical contact level gauge as an input signal, and the output module outputs the detected value of the detecting level module.

[0030] The beneficial effects of this invention are as follows: This invention provides a method and system for measuring water level at electrical contacts based on dual sliding window detection. Addressing the problem of scaling on electrical contact water level gauge probes in existing technologies, this invention designs a dual sliding window detection method to measure the resistance change of the electrical contact water level gauge probe. The method provided in this embodiment uses the energy ratio within the dual sliding window as the decision variable. By comparing the decision variable with two set thresholds, the immersion status of the electrical contact water level probe is monitored. By comprehensively considering the resistance change of the electrical contact water level gauge probe over a period of time, the decision variable for water level judgment becomes more significant and more reasonable than traditional methods, effectively extending the service life of the electrical contact probe after scaling. Attached Figure Description

[0031] The technical solution and other beneficial effects of this application will become apparent from the following detailed description of specific embodiments in conjunction with the accompanying drawings.

[0032] Figure 1 This is a schematic diagram showing the change in the equivalent resistance of an electric contact water level gauge as the measured water level changes.

[0033] Figure 2 This is a flowchart illustrating the electrical contact water level measurement method based on dual sliding window detection provided in this embodiment.

[0034] Figure 3 This is a schematic diagram of the dual sliding window detection provided in this embodiment.

[0035] Figure 4 This is a schematic diagram of the electrical contact water level gauge provided in this embodiment.

[0036] Figure 5 This is a schematic diagram of the installation of the electric contact water level gauge provided in this embodiment. Detailed Implementation

[0037] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0038] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0039] The following disclosure provides many different embodiments or examples for implementing different structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, various specific examples of processes and materials are provided in this application, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0040] An electric contact level gauge is a discontinuous liquid level measuring device. Between the two electrodes at the probe of the electric contact level gauge is a section of insulator with a high resistance. The basic working principle of the electric contact level gauge is based on the significant difference in conductivity between water, air, or water vapor. It determines whether the electrodes are submerged by measuring the equivalent resistance between the electrodes and comparing it to a preset threshold. When the corresponding electric contact level gauge is submerged, the surface of the insulator between the two electrodes is coated with a low-resistance working fluid, resulting in a low-resistance state between the two electrodes; conversely, when the electric contact level gauge is not submerged, the two electrodes exhibit a high-resistance state. By measuring the impedance state between the two electrodes in real time and comparing it to a set impedance threshold, it is possible to determine whether the electric contact level gauge is submerged, thereby detecting the water level height in the measuring cylinder.

[0041] Figure 1 This is a schematic diagram showing the change in the equivalent resistance of an electric contact water level gauge as the measured water level changes. (Example:) Figure 1As shown, when the electric contact level gauge probe is not in contact with water, the equivalent resistance of the electric contact level gauge is in a high-resistance state, which is much greater than the detection threshold. When the equivalent resistance of the electric contact level gauge probe is lower than the detection threshold, it can be determined that the probe is in contact with water and conducting, thereby obtaining the water level in the container being measured. However, as the electric contact level gauge probe is used for longer periods, its equivalent resistance decreases due to continuous scaling. If the equivalent resistance of the electric contact level gauge is lower than the set detection threshold, the electric contact level gauge probe will be considered "short-circuited" and will be unable to correctly detect the water level.

[0042] Therefore, this embodiment provides a method for measuring the water level of electrical contacts based on dual sliding window detection. The ratio of energy within the dual sliding window is used as a decision variable. By comparing the decision variable with two set thresholds, the immersion status of the electrical contact water level probe is monitored.

[0043] Figure 2 This is a flowchart illustrating the electrical contact water level measurement method based on dual sliding window detection provided in this embodiment. Figure 2 As shown, the method for measuring water level at electrical contacts based on dual sliding window detection includes the following steps:

[0044] S1. Continuously measure the equivalent resistance of the electrical contact level gauge located inside the measuring cylinder;

[0045] S2. The equivalent resistance of the continuously recorded electrical contact level gauge is used as the input signal of the detection module. The output signal passes through two continuous sliding windows A and B, and the energy a of sliding window A and sliding window B is calculated respectively. n and b n and the judgment variable m n ;

[0046] S3. Determine the value of the switch signal S0, wherein the initial value of the switch signal S0 is 0;

[0047] S4. If the switch signal S0 is 0, then continue to detect the decision variable m. n If the decision variable m n If the water level is less than the probe's water contact threshold H1, then the switch signal S0 outputs S0 = 1; otherwise, it outputs S0 = 0. If the switch signal S0 is 1, then the decision variable m continues to be detected. n If the decision variable m n If the value is greater than the probe's water outlet threshold H2, then the switch signal S0 outputs S0 = 0; otherwise, it outputs S0 = 1.

[0048] S5. Output the result, update and register the current switch signal S0, and return to step S3;

[0049] Among them, an and b n This represents the cumulative sum of the current input resistance value over the window length, and the decision variable m n The ratio of the energy of the two sliding windows; S0 = 1, which means the electric contact level gauge probe is submerged in water; S0 = 0, which means the electric contact level gauge probe is not submerged in water.

[0050] Specifically, in step S1, the power module applies a voltage signal to the two poles of the electric contact level gauge, while simultaneously measuring the current signal at the two poles of the electric contact level gauge, calculating the equivalent resistance of the electric contact level gauge, and generating a real-time resistance measurement curve.

[0051] In step S2, the length of the sliding window A is M, and the length of the sliding window B is L; wherein the length M of the sliding window A is equal to the length L of the sliding window B, and the sliding window A and the sliding window B are relatively stationary when sliding to the right.

[0052] In step S2, the energy a of the sliding window A n for:

[0053]

[0054] Where, r n To calculate the nth equivalent resistance value, M is the length of the sliding window A, and a n This is the cumulative sum of the current input resistance value data over the length of the sliding window A.

[0055] The energy b of the sliding window A n for:

[0056]

[0057] Where, r n To calculate the nth equivalent resistance value, L is the length of the sliding window B, and b n This is the cumulative sum of the current input resistance value data over the length of the sliding window B.

[0058] In step S2, the decision variable m n for:

[0059] Specifically, a n and b n This represents the cumulative sum of the current input resistance value over a window length. This type of summation is called a sliding window. Its principle is that at each time step n, a new value is added to the summation while an old value is discarded. By considering the resistance change over a period of time within a window length, the decision variable regarding water level becomes more significant.

[0060] Figure 3 This is a schematic diagram of the dual sliding window detection provided in this embodiment. Figure 3 As shown, the equivalent resistance curve of the electrical contact water level gauge probe is regarded as the input signal of the sliding window detection end. Window A and window B are two continuous windows of equal length, and window A and window B are relatively stationary when sliding to the right.

[0061] In step S3, the value of the switching signal S0 is determined. If the switching signal S0 = 0, it means that the probe of the electric contact level gauge was not submerged in water in the previous moment. If the switching signal S0 = 1, it means that the probe of the electric contact level gauge was submerged in water in the previous moment.

[0062] In step S4, when the electric contact level gauge is not in contact with water, the equivalent resistance of the electric contact level gauge is in a high-resistance state, and the cumulative sum of the resistance values ​​in sliding window A and sliding window B is a. n and b n Similarly, the decision variable m n It is in a flat state.

[0063] In step S4, when the electric contact level gauge comes into contact with water, the equivalent resistance of the electric contact level gauge becomes low, and the input signal of the detection module shows a falling edge. When the falling edge of the data reaches the sliding window A, the energy a of the sliding window A... n The resistance will be reduced until the data contained in the sliding window A are all low resistance values, while the energy b of the sliding window B... n When the resistance is high, the decision variable m... n It reaches its lowest value; then the sliding window B begins to show a falling edge, and the decision variable m n The value begins to increase. When the data contained in the sliding window B are all low-resistance values, the decision variable m... n It is in a flat state.

[0064] In step S4: when the decision variable m n When the water level is less than the probe's water contact threshold H1, it indicates a rising water level, and the electrical contact water level gauge is submerged; when the decision variable m n When the water level is greater than the probe's water outlet threshold H2, it indicates that the water level has dropped and the electrical contact water level gauge is above the water level.

[0065] Specifically, such as Figure 3 As shown, when the electrical contact level gauge is not in contact with water, the equivalent resistance of the probe is in a high-resistance state. The cumulative sum of the resistance values ​​in the sliding window A and the sliding window B is the same, that is, the energy of the signal in the sliding window A and the sliding window B is equal, and the resulting response is flat.

[0066] As shown Figure 3 When the electric contact water level gauge contacts water, the equivalent resistance value of the probe starts to decrease, and a falling edge appears in the input signal. When the data falling edge reaches the sliding window A, the energy in the sliding window A will continuously decrease until all the data in the entire window are of low resistance value. At this time, the decision variable m n will drop to the minimum value, which corresponds to all the data in the sliding window A being of low resistance value and all the data in the sliding window B being of high resistance value. After this moment, the data in the sliding window B starts to include low resistance values, and the decision variable m n starts to increase. When all the data in the sliding window B are of low resistance value, the decision variable m n returns to being flat.

[0067] When the probe of the electric contact water level gauge continuously remains in water, the decision variable m n will remain flat. Similarly, when the water level drops and the equivalent resistance of the probe of the electric contact water level gauge rises after the probe is not in contact with water, a rising edge appears in the equivalent resistance curve at this time, and the decision variable m n will first increase and then decrease.

[0068] In the prior art, the decision variable m n is the equivalent resistance value of the probe at the current moment, and it is compared with a set fixed threshold H. If m n <H, it means the probe is submerged in water, otherwise the probe is above the water surface. However, the decision variable m n in the embodiment of the present invention can actually be regarded as a differentiator, and its value will be relatively large when the cumulative sum of the input resistance value changes violently. According to the changes of the decision variable m n , a water contact threshold H1 and a water outlet detection threshold H2 are respectively set. The water level height needs to be judged by combining the two thresholds: when m n <H1, it means the water level is rising and the probe is submerged in water, and this state continues until m n >H2. At this time, the water level drops and the probe position is higher than the water level until the decision variable m n <H1 is detected again, and the probe is submerged in water again.

[0069] Figure 4 is the structural schematic diagram of the electric contact water level gauge provided by this embodiment. Figure 5 is the measurement and installation schematic diagram of the electric contact water level gauge provided by this embodiment.

[0070] As Figure 4 , Figure 5 shown, the embodiment of the present invention also provides an electric contact water level measurement system with double sliding window detection. The electric contact water level measurement system with double sliding window detection includes:

[0071] A measuring cylinder connected to the container being measured;

[0072] An electrical contact level gauge distributed inside the measuring cylinder for measuring the water level height of the sampled water column;

[0073] The power module connected to the electric contact level gauge is used to provide power to the electric contact level measurement system with dual sliding window detection.

[0074] A microcontroller connecting the electrical contact water level gauge and the power module, the microcontroller including a resistance measurement module, a water level detection module and an output module;

[0075] The measuring resistance module measures the equivalent resistance of the electrical contact level gauge in real time, the detecting level module detects the water level in real time based on the equivalent resistance of the electrical contact level gauge as an input signal, and the output module outputs the detected value of the detecting level module.

[0076] like Figure 4 As shown, the electrical contact level gauge includes an anode and a cathode. A lower end cap is provided on the anode, and an upper end cap is provided on the cathode. An insulator is provided between the anode and the cathode. The anode lead is connected to the anode through the lower end cap, and the cathode lead is connected to the cathode through the upper end cap. The anode lead and the cathode lead are respectively connected to the power module and the microcontroller.

[0077] Specifically, in addition to Figure 5 In addition to the single-probe installation method, common industrial installation methods include dual-probe and multi-probe installations. Dual-probe installation involves installing two water level probes at a single measurement point; when both probes are simultaneously submerged, they output a water level signal. Multi-probe installation involves installing multiple electrical contact water level gauges at equal or non-equal intervals on the measuring cylinder for discontinuous water level measurement. The electrical contact water level measurement method based on dual sliding window detection provided in this invention can be used in conjunction with the above installation methods, extending the service life of the electrical contact water level gauge by 50% in environments with poor water quality and where probes are prone to scaling.

[0078] This invention provides a method and system for measuring water level at electrical contacts based on dual sliding window detection. Addressing the issue of scaling on electrical contact water level gauge probes in existing technologies, this invention designs a dual sliding window detection method to detect changes in the probe's resistance. The method uses the energy ratio within the dual sliding windows as the decision variable. By comparing this decision variable with two set thresholds, the immersion status of the electrical contact water level probe is monitored. By comprehensively considering the resistance change of the electrical contact water level gauge probe over a period of time, the decision variable for water level determination becomes more significant and more reasonable than traditional methods, effectively extending the service life of the electrical contact probe after scaling.

[0079] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the present invention. Finally, it should be noted that in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0080] The above provides a detailed description of the electrical contact water level measurement method and system based on dual sliding window detection provided in the embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the technical solutions and core ideas of this application. Those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A method for measuring water level at electrical contacts based on dual sliding window detection, characterized in that, Including the following steps: S1. Continuously measure the equivalent resistance of the electrical contact level gauge located inside the measuring cylinder; S2. The equivalent resistance of the continuously recorded electrical contact level gauge is used as the input signal of the detection module. The input signal passes through two continuous sliding windows A and B, and the energy a of sliding window A and sliding window B is calculated respectively. n and b n and the judgment variable m n ; S3. Determine the value of the switch signal S0, wherein the initial value of the switch signal S0 is 0; S4. If the switch signal S0 is 0, then continue to detect the decision variable m. n If the decision variable m n If the water level is less than the probe's water contact threshold H1, then the switch signal S0 outputs S0=1; otherwise, it outputs S0=0. If the switch signal S0 is 1, then the decision variable m continues to be detected. n If the decision variable m n If the value is greater than the probe's water outlet threshold H2, then the switch signal S0 outputs S0=0; otherwise, it outputs S0=1. S5. Output the result, update and register the current switch signal S0, and return to step S3; Among them, a n and b n This represents the cumulative sum of the current input resistance value over the window length, and the decision variable m n The ratio of the energy of the two sliding windows; S0=1 indicates that the electric contact level gauge probe is submerged in water; S0=0 indicates that the electric contact level gauge probe is not submerged in water.

2. The method for measuring water level at electrical contacts based on dual sliding window detection according to claim 1, characterized in that, In step S1, the power module applies a voltage signal to the two poles of the electric contact level gauge, and simultaneously measures the current signal at the two poles of the electric contact level gauge, calculates the equivalent resistance of the electric contact level gauge, and generates a real-time resistance measurement curve.

3. The method for measuring water level at electrical contacts based on dual sliding window detection according to claim 1, characterized in that, In step S2, the length of the sliding window A is M, and the length of the sliding window B is L; wherein the length M of the sliding window A is equal to the length L of the sliding window B, and the sliding window A and the sliding window B are relatively stationary when sliding to the right.

4. The method for measuring water level at electrical contacts based on dual sliding window detection according to claim 3, characterized in that, In step S2, the energy a of the sliding window A n for: Where, r n To calculate the nth equivalent resistance value, M is the length of the sliding window A, and a n This is the cumulative sum of the current input resistance value data over the length of the sliding window A.

5. The method for measuring water level at electrical contacts based on dual sliding window detection according to claim 4, characterized in that, In step S2, the energy b of the sliding window A n for: ， Where, r n To calculate the nth equivalent resistance value, L is the length of the sliding window B, and b n This is the cumulative sum of the current input resistance value data over the length of the sliding window B.

6. The method for measuring water level at electrical contacts based on dual sliding window detection according to claim 5, characterized in that, In step S4, when the electric contact level gauge is not in contact with water, the equivalent resistance of the electric contact level gauge is in a high-resistance state, and the cumulative sum of the resistance values ​​in sliding window A and sliding window B is a. n and b n Similarly, the decision variable m n It is in a flat state.

7. The method for measuring water level at electrical contacts based on dual sliding window detection according to claim 6, characterized in that, In step S4, when the electric contact level gauge comes into contact with water, the equivalent resistance of the electric contact level gauge becomes low, and the input signal of the detection module shows a falling edge. When the falling edge of the data reaches the sliding window A, the energy a of the sliding window A... n The resistance will be reduced until the data contained in the sliding window A are all low resistance values, while the energy b of the sliding window B... n When the resistance is high, the decision variable m... n It reaches its lowest value; then the sliding window B begins to show a falling edge, and the decision variable m n The value begins to increase. When the data contained in the sliding window B are all low-resistance values, the decision variable m... n It is in a flat state.

8. The method for measuring water level at electrical contacts based on dual sliding window detection according to claim 7, characterized in that, In step S4: when the decision variable m n When the water level is less than the probe's water contact threshold H1, it indicates a rising water level, and the electrical contact water level gauge is submerged; when the decision variable m n When the water level is greater than the probe's water outlet threshold H2, it indicates that the water level has dropped and the electrical contact water level gauge is above the water level.

9. A dual-sliding-window detection electrical contact water level measurement system, wherein the measurement is performed using the method described in any one of claims 1-8, characterized in that, The electrical contact water level measurement system with dual sliding window detection includes: A measuring cylinder connected to the container being measured; An electrical contact level gauge distributed inside the measuring cylinder for measuring the water level height of the sampled water column; The power module connected to the electric contact level gauge is used to provide power to the electric contact level measurement system with dual sliding window detection. A microcontroller connecting the electrical contact water level gauge and the power module, the microcontroller including a resistance measurement module, a water level detection module and an output module; The measuring resistance module measures the equivalent resistance of the electrical contact level gauge in real time, the detecting level module detects the water level height in real time based on the equivalent resistance of the electrical contact level gauge as an input signal, and the output module outputs the detected value of the detecting level module.

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