A strong anti-interference electrostatic induction method pipeline dust concentration detection device and method

Abstract

The present invention relates to a strong anti-interference type electrostatic induction method pipeline dust concentration detection device and method, belonging to the field of dust concentration detection technology. The device includes a rotating body, an insulator, and an insulating sleeve, a metal shielding body and a detection electrode wrapped inside the insulator; the rotating body is covered outside the insulator; the detection electrode is sandwiched between the insulating sleeve and the insulator; the insulating sleeve is wrapped around the metal shielding body to isolate the detection electrode from the metal shielding body; the metal shielding body is grounded through a wire; one end of the detection electrode is suspended to detect dust particles passing through the gap between the shielding bodies, and the other end is connected to a signal processing circuit. The present invention improves the accuracy and stability of the pipeline electrostatic induction method dust concentration sensor.

Description

Technical Field

[0001] The invention belongs to the technical field of dust concentration detection, and relates to a pipeline dust concentration detection device and method using a strong anti-interference electrostatic induction method. Background Art

[0002] The electrostatic induction method is used to realize the online detection of dust concentration in dust conveying pipelines. It is mainly used in dust conveying pipelines in steel mills, cement plants, coal-fired power plants, etc. It is necessary to monitor the concentration parameters of dust particles in the pipeline in real time and adjust the operating conditions of the equipment. Therefore, accurate detection of pipeline dust concentration parameters is a prerequisite for ensuring the safe and effective operation of the equipment.

[0003] The current electrostatic induction pipeline dust concentration sensor mainly uses rod electrodes. The rod-shaped metal rod is inserted into the dust pipe as a detection electrode. When the charged dust particles pass through the metal detection electrode, a certain amount of current signal will be induced on the surface of the metal detection electrode. The dust concentration is detected by analyzing the current signal strength. However, the rod-shaped electrode has poor anti-interference performance. External static electricity and static electricity on the surface of the dust pipe can easily cause strong noise on the surface of the metal detection electrode, affecting the detection accuracy and stability of the sensor. Therefore, the current pipeline electrostatic dust concentration sensor needs to be redesigned. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a highly anti-interference type electrostatic induction method pipeline dust concentration detection device and method to solve the problems of poor stability, large fluctuations and susceptibility to external interference of the current pipeline dust concentration sensor, and to improve the accuracy and stability of the pipeline electrostatic induction method dust concentration sensor.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A strong anti-interference type electrostatic induction method pipeline dust concentration detection device comprises a rotating body 5, an insulator 1, and an insulating sleeve 2, a metal shielding body 3 and a detection electrode 4 wrapped inside the insulator 1; the rotating body 5 is covered outside the insulator 1;

[0007] The detection electrode 4 is sandwiched between the insulating sleeve 2 and the insulator 1; the insulating sleeve 2 is wrapped around the metal shielding body 3 to isolate the detection electrode 4 from the metal shielding body 3;

[0008] The metal shielding body 3 is grounded through a wire; one end of the detection electrode 4 is suspended in the air for detecting dust particles passing through the gaps between the shielding bodies, and the other end is connected to the signal processing circuit.

[0009] Preferably, the detection electrodes 4 include two electrodes, which are sandwiched between two metal shielding bodies 3 .

[0010] Preferably, two symmetrical long holes are provided in the middle of the rotating body 5.

[0011] Preferably, the width of the long hole of the rotating body is greater than the hollow distance between the two detection electrodes 4.

[0012] Preferably, when the long hole of the rotating body is opposite to the middle channel of the two detection electrodes 4, the particulate matter passes through the long hole of the rotating body and the middle channel, and the detection electrode 4 is in the detection state; when the rotating body 5 rotates 90 degrees, the axis of the long hole of the rotating body is perpendicular to the middle channel of the two detection electrodes 4, and the rotating body 5 prevents the particulate matter from passing through the detection electrode 4, and the detection electrode 4 is in the zero calibration state, and the signal output by the detection electrode 4 is the zero value.

[0013] Preferably, the detection method of the pipeline dust concentration detection device specifically includes the following steps:

[0014] 1) Rotate the rotating body 5 at the outer end of the detection electrode 4 to make the detection device in the zero calibration state, and calculate the standard deviation a1 of the signal output by the detection electrode 4 as the zero value;

[0015] 2) Rotate the rotating body 5 at the outer end of the detection electrode 4 to make the detection device in the detection state, calculate the standard deviation a0 of the signal output by the detection electrode 4, subtract the zero value, a = a0 - a1, as the detection value;

[0016] 3) Set a threshold b, where the threshold b is less than the standard deviation of the external interference signal, that is, a0 < b < a2, where a2 is the standard deviation of the additional static power source interference signal; if the detection value a is greater than or equal to the threshold b, the value is invalid and re-detection is required; if the detection value a is less than the threshold b, the detection value a is a valid value, and the dust concentration value c is obtained by multiplying by the calibration coefficient k.

[0017] The beneficial effects of the present invention are as follows: By improving the electrodes of the existing pipeline electrostatic induction method dust concentration sensor and optimizing the fluctuation signal extraction algorithm, the anti-interference ability of the electrostatic induction method pipeline dust concentration sensor is improved, and the accuracy and stability of the electrostatic induction method pipeline dust concentration sensor are ensured.

[0018] Other advantages, objectives and features of the present invention will be described to some extent in the subsequent specification, and to some extent, will be obvious to those skilled in the art based on the study of the following text, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following specification. Description of the Drawings

[0019] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be described in detail preferably with reference to the accompanying drawings, where:

[0020] Figure 1 It is a side cross-sectional view of the pipeline dust concentration detection device using the electrostatic induction method of Example 1;

[0021] Figure 2 It is a top view of the cross-sectional view of the pipeline dust concentration detection device using the electrostatic induction method according to Example 1;

[0022] Figure 3 It is a schematic diagram of the structure of the electrostatic induction method pipeline dust concentration detection device in two states of Example 1;

[0023] Figure 4 This is a flow chart of the detection method of the pipeline dust concentration detection device using the electrostatic induction method in Example 1;

[0024] Figure numerals: 1 - insulator, 2 - insulating sleeve, 3 - metal shielding body, 4 - detection electrode, 5 - rotating body. DETAILED DESCRIPTION

[0025] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0026] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0027] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0028] Embodiment 1:

[0029] See also Figure 1 to Figure 4 This embodiment provides a strong anti-interference type electrostatic induction method pipeline dust concentration detection device, including an insulator 1, an insulating sleeve 2, a metal shielding body 3, an induction detection electrode assembly 4 and a rotating body 5.

[0030] Insulator 1: The material is polytetrafluoroethylene, and its main function is to provide a high insulation impedance between the detection electrode 4 and the outside world. On the one hand, it prevents the water vapor in the pipeline from affecting the stability of the induced charge on the surface of the detection electrode and avoids the water vapor from eliminating the induced charge. On the other hand, it eliminates the charge transfer between the dust particles and the detection electrode caused by the friction between the dust particles and the detection electrode. The purpose of the sensor is to obtain the induced signal rather than transfer the charge;

[0031] Insulation sleeve 2: a PVC hose rubber sleeve is used, and the PVC insulation sleeve is wrapped around the metal shielding body 3 by heating to shrink the PVC insulation sleeve, so as to isolate the detection electrode 4 from the metal shielding body 3 and prevent the induced charge of the detection electrode 4 from being discharged to the ground;

[0032] Metal shield 3: Made of 304 stainless steel, it is directly connected to the ground through a wire. In terms of the overall structure, the detection electrode 4 is sandwiched between two metal shields 3. The detection electrode 4 can accurately detect dust particles passing through the gaps in the middle of the shields, effectively shielding external interference and ensuring the stability of the sensing signal on the surface of the detection electrode.

[0033] Detection electrode 4: It uses H62 copper sheet, which is sandwiched between the insulating sleeve 2 and the insulator 1. It has a high insulation impedance with the outside world and the shielding body. It detects dust particles passing through the gaps between the shielding bodies. It is the signal source of the electrostatic induction dust concentration sensor, and its function is equivalent to the metal rod of the current rod-shaped electrode.

[0034] Rotating body 5: Made of polytetrafluoroethylene, the rotating body 5 can be manually controlled to rotate freely. When the long hole of the rotating body is opposite to the axis of the long hole of the detection electrode, the particles pass through the long hole of the rotating body and the long hole of the detection electrode, and the detection electrode is in a detection state; when the rotating body 5 rotates 90 degrees, the axis of the long hole of the rotating body is perpendicular to the axis of the long hole of the detection electrode, the rotating body 5 prevents the particles from passing through the detection electrode, and the signal output by the detection electrode is a zero value, which is mainly caused by power supply noise and industrial frequency noise and is inevitable.

[0035] The induction signal extraction algorithm of the electrostatic induction method pipeline dust concentration detection device in this embodiment is as follows: dust particles induce a fluctuating signal on the surface of the detection electrode 4, and the dust concentration is detected by analyzing the intensity of the fluctuating component of the fluctuating signal. The fluctuating signal includes the induction signal of the dust particles, the power frequency noise, and the external static power source interference signal.

[0036] Zero value measurement: Through the detection electrode 4 designed with high anti-interference ability, the industrial frequency clutter interference on the surface of the detection electrode and the external electromagnetic radiation interference are very small. This noise exists for a long time and is relatively stable. When no dust particles pass through the detection electrode 4, the standard deviation of the output signal of the detection electrode is calculated as a1, and this value is used as the zero value of the detection electrode. By adjusting the detection electrode to the zero calibration state, the standard deviation of the output signal of the detection electrode can be obtained.

[0037] Interference noise measurement: The interference signal intensity of the external static power source is relatively high, such as the static electricity interference of the human body, etc. The static electricity amount of the human body is much larger than the electric charge carried by the dust particles. The interference noise intensity is high and the duration is short. The standard deviation of the additional static power source interference signal is a2.

[0038] Dust particle induction value detection: When dust particles pass through the detection electrode 4, the dust particles induce a certain amount of fluctuating signal on the surface of the detection electrode. Without external interference, the output signal of the detection electrode is the superposition of the zero value noise and the dust particle induction signal. The standard deviation value of the output signal is calculated as a0.

[0039] Through test analysis, a1 < a0 < a2; Therefore, a threshold b is designed to eliminate the industrial frequency, electromagnetic radiation interference and human static power source interference. The specific data processing algorithm is as Figure 4 shown, and specifically includes the following steps:

[0040] 1) Rotate the rotating body 5 at the outer end of the detection electrode 4. The detection device is in the zero calibration state, and the standard deviation a1 of the output signal of the detection electrode 4 is calculated as the zero value.

[0041] 2) Rotate the rotating body 5 at the outer end of the detection electrode. The detection device is in the detection state, and the standard deviation a0 of the output signal of the detection electrode 4 is calculated, and the zero value is subtracted, a = a0 - a1, as the detection value.

[0042] 3) Set the threshold b, and the threshold b is less than the standard deviation of the external interference signal, that is, a0 < b < a2. If the detection value a is greater than or equal to the threshold b, the value is invalid and re-detection is required; if the detection value a is less than the threshold b, the detection value a is the valid value, and the dust concentration value c is obtained by multiplying it by the calibration coefficient k.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the purpose and scope of the present technical solution, and they should all be covered by the scope of the claims of the present invention.

Claims

1. A strong anti-interference type electrostatic induction method pipeline dust concentration detection device, characterized in that: The device includes a rotating body (5), an insulator (1), and an insulating sleeve (2), a metal shielding body (3), and a detection electrode (4) enclosed inside the insulator (1); the rotating body (5) covers the outside of the insulator (1). The detection electrode (4) is sandwiched between the insulating sleeve (2) and the insulator (1); the insulating sleeve (2) wraps around the metal shielding body (3) to isolate the detection electrode (4) from the metal shielding body (3). The metal shielding body (3) is grounded through a wire; one end of the detection electrode (4) is suspended for detecting dust particles passing through the gap between the shielding bodies, and the other end is connected to a signal processing circuit; two symmetrical long holes are provided in the middle of the rotating body (5); the width of the long holes in the rotating body is greater than the hollowing distance between the two detection electrodes (4); when the long holes in the rotating body are opposite to the middle channel of the two detection electrodes (4), the particulate matter passes through the long holes in the rotating body and the middle channel, and the detection electrode (4) is in the detection state; when the axis of the long holes in the rotating body is perpendicular to the middle channel of the two detection electrodes (4), the rotating body (5) prevents the particulate matter from passing through the detection electrode (4), the detection electrode (4) is in the zero calibration state, and the signal output by the detection electrode (4) is the zero value. The detection method of this device specifically includes the following steps: 1) Rotate the rotating body (5) to make the detection device in the zero calibration state, and calculate the standard deviation a1 of the signal output by the detection electrode (4) as the zero value. 2) Rotate the rotating body (5) to make the detection device in the detection state, calculate the standard deviation a0 of the signal output by the detection electrode (4), and subtract the zero value, a = a0 - a1, as the detection value. 3) Set a threshold b, where the threshold b is less than the standard deviation of the external interference signal, that is, a0 < b < a2, where a2 is the standard deviation of the additional static power source interference signal; if the detection value a is greater than or equal to the threshold b, the value is invalid and re-detection is required; if the detection value a is less than the threshold b, the detection value a is the effective value, and multiplying by the calibration coefficient k gives the dust concentration value c.

2. The strong anti-interference electrostatic induction method pipeline dust concentration detection device according to claim 1 is characterized in that: The detection electrode (4) includes two and is sandwiched between the two metal shielding bodies (3).

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