A square wave signal-based turbine flow sensor self-diagnosis method

Abstract

This invention provides a self-diagnostic method for turbine flow sensors based on square wave signals, belonging to the field of turbine flow sensor technology. The method includes: constructing a dual-turbine structure; rotating the dual-turbine structure according to a preset speed ratio in response to the flow of medium through the turbine flow sensor, and acquiring the rotational state of the dual-turbine structure; installing a Hall sensor above the dual-turbine structure and constructing a signal detection circuit; acquiring the speed signal based on the rotational state of the dual-turbine structure using the signal detection circuit, and converting the speed signal into a square wave signal; using a microcontroller to collect the frequency of the square wave signal and calculate the current turbine speed; calculating the current speed ratio of the dual-turbine structure and comparing it with a preset speed ratio to determine the working condition of the turbine flow sensor, and feeding back the determination result. This invention solves the problems of difficult flow detection and lack of self-diagnostic capability in existing turbine flow sensors.

Description

Technical Field

[0001] This invention belongs to the field of turbine flow sensor technology, and particularly relates to a self-diagnostic method for turbine flow sensors based on square wave signals. Background Technology

[0002] Turbine flow sensors are precision flow measurement instruments widely used in petroleum, chemical, metallurgical, and scientific research fields. During use, impurities in the medium or those introduced during installation can enter the pipeline and, upon passing through the turbine flow sensor, cause wear or jamming of its turbine, bearings, or other components, making flow detection difficult. Furthermore, existing turbine flow sensors lack self-diagnostic capabilities. Summary of the Invention

[0003] To address the aforementioned shortcomings in the existing technology, this invention provides a self-diagnostic method for turbine flow sensors based on square wave signals, which solves the problems of difficult flow detection and lack of self-diagnostic capability in existing turbine flow sensors.

[0004] To achieve the above objectives, the technical solution adopted by this invention is: a self-diagnostic method for a turbine flow sensor based on square wave signals, comprising the following steps: S1. Construct a dual-turbine structure. In response to the medium flowing through the turbine flow sensor, rotate the dual-turbine structure according to a preset speed ratio to obtain the rotational state of the dual-turbine structure. S2. Install the Hall sensor on top of the dual-turbine structure and build a signal detection circuit. Based on the rotational state of the dual-turbine structure, use the signal detection circuit to obtain the rotational speed signal and convert the rotational speed signal into a square wave signal. S3. Using a microcontroller, the frequency of the square wave signal is collected and calculated to obtain the current turbine speed. By calculating the current speed ratio of the dual-turbine structure and comparing it with the preset speed ratio, the working status of the turbine flow sensor is determined, and the determination result is fed back to complete the self-diagnosis of the turbine flow sensor.

[0005] The beneficial effects of this invention are as follows: By constructing a dual-turbine structure and designing a signal detection circuit to convert the rotational speed signal into a square wave signal, and comparing the current rotational speed ratio with the preset rotational speed ratio, feedback is provided through a microcontroller, which reduces the difficulty of flow detection and realizes the self-diagnosis of the turbine flow sensor.

[0006] Further, S1 includes the following steps: S101. Based on the turbine flow sensor and combined with the preset speed ratio, different blade shapes are used to design the front turbine and the rear turbine, and a dual-turbine structure including the front turbine and the rear turbine is constructed. S102. In response to the medium flowing through the turbine flow sensor, the front turbine and the rear turbine are rotated according to a preset speed ratio to obtain the rotational state of the dual-turbine structure.

[0007] The beneficial effects of the above-mentioned further solutions are as follows: By designing a front turbine and a rear turbine to construct a dual-turbine structure, and forming a precise comparison basis according to a preset speed ratio, the present invention improves the diagnostic accuracy of the turbine flow sensor.

[0008] Furthermore, S2 includes the following steps: S201. A Hall sensor with its own back magnet is used as the sensor and installed above the dual turbine structure to build a signal detection circuit. S202. Based on the rotational state of the dual-turbine structure, the turbine speed signal is obtained using a signal detection circuit; S203. Based on the principle that when the turbine blade is close to the Hall sensor, the signal detection circuit outputs a low level, and when the turbine blade is far away from the Hall sensor, the signal detection circuit outputs a high level, the conversion formula is obtained. S204. Based on the turbine speed signal, the square wave signal is calculated using the conversion expression.

[0009] Furthermore, the signal detection circuit includes: a first sub-circuit and a second sub-circuit; The first sub-circuit is used to detect the turbine speed signal of the front turbine in the dual-turbine structure, and includes: Hall sensor N1, capacitor C1, capacitor C3, resistor R1 and diode V1; The first pin of the Hall sensor N1 is connected to a +15V power supply and one end of capacitor C1; the second pin of the Hall sensor N1 is connected to the other end of capacitor C1 and one end of capacitor C3; the third pin of the Hall sensor N1 is connected to the negative terminal of diode V1; the other end of capacitor C3 is connected to the positive terminal of diode V1 and one end of resistor R1; the other end of resistor R1 is connected to a 3.3V pull-up power supply. The second sub-circuit is used to detect the turbine speed signal of the rear turbine in the dual-turbine structure, and includes: Hall sensor N2, capacitor C2, capacitor C4, resistor R2 and diode V2; The first pin of the Hall sensor N2 is connected to a +15V power supply and one end of capacitor C2; the second pin of the Hall sensor N2 is connected to the other end of capacitor C2 and one end of capacitor C4; the third pin of the Hall sensor N2 is connected to the negative terminal of diode V2; the other end of capacitor C4 is connected to the positive terminal of diode V2 and one end of resistor R2; the other end of resistor R2 is connected to a 3.3V pull-up power supply.

[0010] Furthermore, the conversion formula is as follows: ; in, Indicates the frequency of the square wave signal. Indicates turbine speed. This represents the conversion factor.

[0011] The beneficial effects of the above-mentioned further solutions are as follows: By installing the Hall sensor above the dual-turbine structure, constructing a signal detection circuit, and using the signal principle between the turbine blades and the Hall sensor to obtain the conversion formula, the turbine blade position is accurately determined through the precise conversion of the square wave signal, thereby accurately measuring the turbine speed and improving the efficiency of the turbine flow sensor's self-diagnosis.

[0012] Furthermore, step S3 includes the following steps: S301. Using a microcontroller, a square wave signal is acquired, and the current turbine speed, including the front turbine speed and the rear turbine speed, is obtained by solving the square wave signal based on its frequency. S302. Calculate the current speed ratio of the dual-turbine structure based on the front turbine speed and the rear turbine speed; S303. Compare the current speed ratio with the preset speed ratio. If the current speed ratio is consistent with the preset speed ratio, the turbine flow sensor is determined to be working normally and a normal working signal is fed back. Otherwise, the turbine flow sensor is determined to be stalled or stuck, and an alarm signal is fed back, prompting the user to inspect the turbine flow sensor, thus completing the turbine flow sensor self-diagnosis.

[0013] The beneficial effects of the above-mentioned further solution are as follows: When the medium flows through the turbine flow sensor, the present invention determines whether the speed ratio of the front turbine and the rear turbine in the dual-turbine structure is the set speed ratio to determine whether the turbine is working normally. When the operation is abnormal, an alarm signal is output to prompt the user to inspect the turbine flow sensor. This can detect turbine stall or jamming of the turbine flow sensor in advance and prevent the turbine flow sensor from continuing to be used when it is working abnormally, which would cause the entire system to operate in an abnormal state. Attached Figure Description

[0014] Figure 1 This is a flowchart of the method of the present invention.

[0015] Figure 2 This is a structural diagram of the self-diagnosis method in this embodiment.

[0016] Figure 3 This is a diagram of the dual-turbine structure in this embodiment.

[0017] Figure 4 This is a circuit diagram of the Hall sensor in this embodiment.

[0018] Among them, 101 is a dual-turbine structure, 102 is a signal detection circuit, 103 is a microcontroller, 201 is a front turbine, 202 is a rear turbine, and 203 is a Hall sensor. Detailed Implementation

[0019] The specific embodiments of the present invention are described below to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0020] Before describing this embodiment, the following terms will be explained: RPM: Rotational speed per minute; DGND: Digital Land.

[0021] Example In this embodiment, the present invention aims to design a novel turbine flow sensor with a dual-turbine assembly having a specific speed ratio. The turbine flow sensor detects the speed of the dual-turbine assembly and compares the dual-turbine speed with the design ratio to determine whether the turbine is stuck by impurities, thus enabling the turbine flow sensor to have self-diagnostic capabilities. The overall steps are as follows: adopting a dual-turbine structure, setting the speed ratio of the front turbine 201 and the rear turbine 202 to a specific value, detecting the turbine speed through the signal detection circuit 102, and then calculating the speed ratio of the front turbine 201 and the rear turbine 202 through the microcontroller 103. When the calculated speed ratio is consistent with the set speed ratio, the working status of the turbine flow sensor is determined, thereby realizing the self-diagnosis of the turbine flow sensor.

[0022] like Figure 1 As shown, this invention provides a self-diagnostic method for turbine flow sensors based on square wave signals, the implementation of which is as follows: S1. Construct a dual-turbine structure. In response to the medium flowing through the turbine flow sensor, rotate the dual-turbine structure according to a preset speed ratio and obtain the rotational state of the dual-turbine structure. The specific steps are as follows: S101. Based on the turbine flow sensor and combined with the preset speed ratio, different blade shapes are used to design the front turbine and the rear turbine, and a dual-turbine structure including the front turbine and the rear turbine is constructed. S102. In response to the medium flowing through the turbine flow sensor, the front turbine and the rear turbine are rotated according to a preset speed ratio to obtain the rotational state of the dual-turbine structure.

[0023] In this embodiment, as Figure 2As shown in the diagram, the self-diagnosis method of the present invention includes: a dual-turbine structure 101, a signal detection circuit 102, and a microcontroller 103, and the microcontroller 103 feeds back the determination result of the working status of the turbine flow sensor to the user. like Figure 3 As shown, a dual-turbine structure 101 is adopted, and the speed ratio of the front turbine 201 and the rear turbine 202 is preset to a specific value. The turbine material is magnetic stainless steel, and the front turbine 201 and the rear turbine 202 adopt different blade designs. The turbine speed under different blade designs is calculated by fluid simulation, and the speed ratio of the front turbine 201 and the rear turbine 202 is determined. When the medium flows through the turbine flow sensor, the front turbine 201 and the rear turbine 202 rotate according to the preset speed ratio, so as to obtain the rotation state of the dual-turbine structure 101 when the medium flows through the turbine flow sensor.

[0024] S2. Install the Hall sensor above the dual-turbine structure and construct a signal detection circuit. Based on the rotational state of the dual-turbine structure, use the signal detection circuit to acquire the rotational speed signal and convert the rotational speed signal into a square wave signal. The specific steps are as follows: S201. A Hall sensor with its own back magnet is used as the sensor and installed above the dual turbine structure to build a signal detection circuit. S202. Based on the rotational state of the dual-turbine structure, the turbine speed signal is obtained using a signal detection circuit; S203. Based on the principle that when the turbine blade is close to the Hall sensor, the signal detection circuit outputs a low level, and when the turbine blade is far away from the Hall sensor, the signal detection circuit outputs a high level, the conversion formula is obtained. S204. Based on the turbine speed signal, the square wave signal is calculated using the conversion expression.

[0025] In this embodiment, as Figure 3 As shown, a Hall sensor 203 with its own back magnet is used as the sensor. The Hall sensor 203 is mounted on top of the dual-turbine structure 101 and constructed as shown in the diagram. Figure 4 The signal detection circuit shown; Based on the rotational state of the dual-turbine structure, the rotational speeds of the front turbine 201 and the rear turbine 202 are detected by a signal detection circuit to obtain turbine speed signals. The turbine speed signal is converted into a square wave signal by outputting a low level when the turbine blade is close to the Hall sensor and a high level when it is far away from the Hall sensor, and the conversion formula is obtained. Therefore, the turbine speed signal is converted using a conversion expression to obtain a square wave signal; The conversion formula is as follows: ; in, This indicates the frequency of a square wave signal, measured in Hertz (Hz). This indicates the turbine speed, measured in RPM. The conversion factor is determined by dividing the number of turbine blades by the time conversion ratio of 60.

[0026] In this embodiment, as Figure 4 As shown, the signal detection circuit includes a first sub-circuit and a second sub-circuit. The specific conversion method is as follows: the Hall sensor 203 is powered by a +15V power supply, the power supply is filtered by capacitor C1 (or capacitor C2), the output signal of the Hall sensor 203 is pulled up by a resistor R1 (or resistor R2), and the output signal F1 (or output signal F2) is connected to the resistor R1 (or resistor R2) by diode V1 (or diode V2). The signal is filtered by capacitor C3 (or capacitor C4). The specific circuit principle is as follows: The first sub-circuit is used to detect the turbine speed signal of the front turbine in the dual-turbine structure, and includes: Hall sensor N1, capacitor C1, capacitor C3, resistor R1 and diode V1; The first pin of the Hall sensor N1 is connected to a +15V power supply and one end of capacitor C1; the second pin of the Hall sensor N1, serving as the DGND pin, is connected to the other end of capacitor C1 and one end of capacitor C3; the third pin of the Hall sensor N1 is connected to the negative terminal of diode V1; the other end of capacitor C3 is connected to the positive terminal of diode V1 and one end of resistor R1; the other end of resistor R1 is connected to a 3.3V pull-up power supply. The second sub-circuit is used to detect the turbine speed signal of the rear turbine in the dual-turbine structure, and includes: Hall sensor N2, capacitor C2, capacitor C4, resistor R2 and diode V2; The first pin of the Hall sensor N2 is connected to a +15V power supply and one end of capacitor C2; the second pin of the Hall sensor N2 is connected to the other end of capacitor C2 and one end of capacitor C4; the third pin of the Hall sensor N2 is connected to the negative terminal of diode V2; the other end of capacitor C4 is connected to the positive terminal of diode V2 and one end of resistor R2; the other end of resistor R2 is connected to a 3.3V pull-up power supply.

[0027] S3. Using a microcontroller, the frequency of the square wave signal is acquired and calculated to obtain the current turbine speed. By calculating the current speed ratio of the dual-turbine structure and comparing it with the preset speed ratio, the working status of the turbine flow sensor is determined, and the determination result is fed back to complete the self-diagnosis of the turbine flow sensor. The specific steps are as follows: S301. Using a microcontroller, a square wave signal is acquired, and the current turbine speed, including the front turbine speed and the rear turbine speed, is obtained by solving the square wave signal based on its frequency. S302. Calculate the current speed ratio of the dual-turbine structure based on the front turbine speed and the rear turbine speed; S303. Compare the current speed ratio with the preset speed ratio. If the current speed ratio is consistent with the preset speed ratio, the turbine flow sensor is determined to be working normally and a normal working signal is fed back. Otherwise, the turbine flow sensor is determined to be stalled or stuck, and an alarm signal is fed back, prompting the user to inspect the turbine flow sensor, thus completing the turbine flow sensor self-diagnosis.

[0028] In this embodiment, the microcontroller 103 acquires the frequency of the square wave signal output by the signal detection circuit and calculates it into the current turbine speed. The current turbine speed includes the front turbine speed and the rear turbine speed. Then, it calculates the speed ratio between the front turbine 201 and the rear turbine 202 to obtain the current speed ratio. The current speed ratio is compared with the preset speed ratio. If the current speed ratio is consistent with the preset speed ratio, it is determined that the turbine flow sensor is working normally and a normal working signal is fed back. Otherwise, it is determined that the turbine flow sensor is stalled or stuck and an alarm signal is fed back to prompt the user to inspect the turbine flow sensor, thus completing the self-diagnosis of the turbine flow sensor. The expression for calculating the turbine speed is as follows: ; in, This indicates the current turbine speed, in RPM. This indicates the frequency of a square wave signal, measured in Hertz (Hz). This represents the conversion factor.

Claims

1. A square wave signal-based turbine flow sensor self-diagnostic method, characterized by, Includes the following steps: S1. Design front and rear turbines with different blade structures according to a preset speed ratio to construct a dual-turbine structure with a preset speed ratio. In response to the medium flowing through the turbine flow sensor, the dual-turbine structure rotates according to the preset speed ratio to obtain the comparative rotational states of the front and rear turbines, specifically: S101. Based on a turbine flow sensor and combined with a preset speed ratio, a dual-turbine structure with a set of preset speed ratios is constructed by using different blade shapes to design the front and rear turbines. S102. In response to the medium flowing through the turbine flow sensor, the front turbine and the rear turbine rotate according to a preset speed ratio to obtain the comparative rotation state of the front turbine and the rear turbine. Specifically: The front turbine and the rear turbine are designed with different blade shapes. The turbine speed under different blade shapes is calculated through fluid simulation. The speed ratio of the front turbine and the rear turbine is determined. When the medium flows through the turbine flow sensor, the front turbine and the rear turbine rotate according to the preset speed ratio. The rotation state of the dual turbine structure when the medium flows through the turbine flow sensor is obtained. S2. Install a Hall sensor with a built-in back magnet on top of the dual-turbine structure and construct a signal detection circuit. Based on the rotational state of the dual-turbine structure, use the signal detection circuit to acquire the rotational speed signal, and convert the rotational speed signal into a square wave signal to obtain the comparative rotational state of the front and rear turbines. Specifically: S201. A Hall sensor with its own back magnetism is used as the sensor and installed above a double turbine structure made of magnetic material to construct a signal detection circuit. S202. Use a signal detection circuit to obtain the turbine speed signal and obtain the comparative rotational states of the front turbine and the rear turbine. The signal detection circuit includes: a first sub-circuit and a second sub-circuit; The first sub-circuit is used to detect the turbine speed signal of the front turbine in the dual-turbine structure, and includes: Hall sensor N1, capacitor C1, capacitor C3, resistor R1 and diode V1; The second sub-circuit is used to detect the turbine speed signal of the rear turbine in the dual-turbine structure, and includes: Hall sensor N2, capacitor C2, capacitor C4, resistor R2 and diode V2; The specific conversion method is as follows: power the Hall sensor through a +15V power supply, filter the power supply through capacitor C1, pull up the output signal of the Hall sensor through a resistor R1, connect the output signal F1 to the resistor R1 through diode V1, and filter the signal through capacitor C3. S203. Based on the principle that when the turbine blade is close to the Hall sensor, the signal detection circuit outputs a low level, and when the turbine blade is far away from the Hall sensor, the signal detection circuit outputs a high level, the conversion formula is obtained. S204. Based on the turbine speed signal, the frequency of the square wave signal is calculated using the conversion expression; The conversion formula is as follows: in, Indicates the frequency of the square wave signal. Indicates turbine speed. Indicates the conversion factor; S3. Using a microcontroller, the frequency of the square wave signal is collected and calculated to obtain the current turbine speed. By calculating the current speed ratio of the dual-turbine structure and comparing it with the preset speed ratio, the working status of the turbine flow sensor is determined, and the determination result is fed back to complete the self-diagnosis of the turbine flow sensor.

2. The self-diagnostic method for turbine flow sensors based on square wave signals according to claim 1, characterized in that, The first pin of the Hall sensor N1 is connected to a +15V power supply and one end of capacitor C1; the second pin of the Hall sensor N1 is connected to the other end of capacitor C1 and one end of capacitor C3; the third pin of the Hall sensor N1 is connected to the negative terminal of diode V1; the other end of capacitor C3 is connected to the positive terminal of diode V1 and one end of resistor R1; the other end of resistor R1 is connected to a 3.3V pull-up power supply. The first pin of the Hall sensor N2 is connected to a +15V power supply and one end of capacitor C2; the second pin of the Hall sensor N2 is connected to the other end of capacitor C2 and one end of capacitor C4; the third pin of the Hall sensor N2 is connected to the negative terminal of diode V2; the other end of capacitor C4 is connected to the positive terminal of diode V2 and one end of resistor R2; the other end of resistor R2 is connected to a 3.3V pull-up power supply.

3. The self-diagnostic method for turbine flow sensors based on square wave signals according to claim 1, characterized in that, S3 includes the following steps: S301. Using a microcontroller, a square wave signal is acquired, and the current turbine speed, including the front turbine speed and the rear turbine speed, is obtained by solving the square wave signal based on its frequency. S302. Calculate the current speed ratio of the dual-turbine structure based on the front turbine speed and the rear turbine speed; S303. Compare the current speed ratio with the preset speed ratio. If the current speed ratio is consistent with the preset speed ratio, the turbine flow sensor is determined to be working normally and a normal working signal is fed back. Otherwise, the turbine flow sensor is determined to be stalled or stuck, and an alarm signal is fed back, prompting the user to inspect the turbine flow sensor, thus completing the turbine flow sensor self-diagnosis.

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