Differential capacitance-based particle detection system and method
By adopting differential capacitive sensor probe and circuit processing technology in the particle detection system, the poor detection accuracy caused by environmental factors is solved, and higher detection accuracy and real-time detection functions are achieved.
Patent Information
- Application Number
- CN202510149457.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-11
- Publication Date
- 2025-05-16
AI Technical Summary
In the prior art, sensors are subject to poor detection accuracy due to interference from environmental factors.
Using a particle detection system based on differential capacitance type, the first and second capacitance signals are outputted through the first sensing unit and the second sensing unit in the sensor probe module, and differential processing is performed through the sensing circuit module to suppress the background noise of the common mode, and finally display the target signal in real time through the computer program.
Effectively eliminate background noise from common mode components, improve the accuracy of target signals, enhance the detection accuracy of pollutant particles, and realize real-time detection and display.
Smart Images
Figure CN120009352A_ABST
Abstract
Description
Technical Field
[0001] The present application belongs to the field of precision measurement, and more specifically, to a particle detection system and method based on differential capacitance. Background Art
[0002] In industrial production, the wear and aging of various machines seriously endanger the life safety of practitioners and affect production efficiency, so the reliability analysis of machines is very important. The size and concentration of pollutant particles in the oil can well characterize the wear condition of the machine, and the reliability analysis of the machine can be realized by detecting oil pollution.
[0003] At the same time, pollutant particles in water bodies also seriously endanger the healthy and sustainable development of human beings and natural ecology. Methods for detecting oil or water pollution usually include optical microscope detection, fiber optic sensing and other methods. The detection accuracy of this method is easily affected by the turbidity of the liquid and the instrument is expensive; the ultrasonic detection method based on acoustics is easily affected by environmental noise and the equipment is bulky and inconvenient to operate; electronic detection methods can be divided into capacitance monitoring, inductance monitoring and resistance monitoring according to basic principles. Among them, the inductance mode is often only sensitive to metal pollutants and has poor detection effect on non-metallic pollutants; the resistance mode has better detection effect on soluble pollutants. Capacitive sensors have excellent properties such as simple structure, low cost, and sensitivity to non-metallic pollutants, but their detection accuracy is easily affected by interference such as environmental noise and liquid pulsation.
[0004] Therefore, how to reduce the interference caused by environmental factors and improve the detection accuracy of sensors is a technical problem that needs to be solved at present. Summary of the invention
[0005] In view of the defects of the prior art, the purpose of the present application is to provide a particle detection system and method based on differential capacitance, aiming to solve the problem of poor detection accuracy of the sensor due to interference from environmental factors.
[0006] To achieve the above objectives, in a first aspect, the present application provides a particle detection system based on differential capacitance, comprising: The sensor probe module includes a first sensing unit and a second sensing unit. The object to be detected passes through the first sensing unit and the second sensing unit successively. When the object to be detected passes through the first sensing unit, the first sensing unit outputs a first capacitance signal, and the second sensing unit outputs a second capacitance signal; when the object to be detected passes through the second sensing unit, the second sensing unit outputs a first capacitance signal, and the first sensing unit outputs a second capacitance signal; the first capacitance signal is obtained based on background noise and a pollutant signal, and the second capacitance signal is obtained based on the background noise; A sensing circuit module, connected to the first sensing unit and the second sensing unit, and configured to perform differential processing on the first capacitance signal and the second capacitance signal to obtain a target signal so as to suppress common-mode background noise; The display module is used to display the target signal in real time through a computer program to realize the detection of pollutant particles and the signal differential noise reduction display.
[0007] Optionally, the sensor probe module includes a first electrode plate, a second electrode plate and a third electrode plate; the length of the first electrode plate is greater than that of the second electrode plate and the third electrode plate; The first electrode plate and the second electrode plate form a first sensing unit, and the first electrode plate and the third electrode plate form a second sensing unit; When the object to be detected passes between the first electrode plate and the second electrode plate, the first electrode plate and the second electrode plate obtain a first capacitance signal according to the background noise and the pollutant signal, and the first electrode plate and the third electrode plate obtain a second capacitance signal according to the background noise; When the object to be detected passes between the first plate and the third plate, the first plate and the third plate obtain a first capacitance signal according to the background noise and the pollutant signal, and the first plate and the second plate obtain a second capacitance signal according to the background noise.
[0008] Optionally, the sensing circuit module includes a front-end circuit, a demodulator and a voltage source connected in sequence; The front-end circuit is connected to the second plate and the third plate respectively through a transformer, and the voltage source is connected to the first plate; The front-end circuit is used to perform differential processing on the first capacitance signal to obtain a differential signal to suppress common-mode background noise; The demodulator is used to demodulate the differential signal to obtain the target signal and transmit it to the display module; The voltage source is used to provide voltage to the first electrode plate and provide the required voltage input for the entire circuit.
[0009] Optionally, the sensing circuit module further includes an AC amplifier circuit, which is connected to the output end of the front-end circuit; the AC amplifier circuit is used to amplify the differential signal to enhance the signal strength.
[0010] In a second aspect, the present application provides a particle detection method based on differential capacitance, comprising: When the object to be detected passes through the first sensing unit, the first sensing unit outputs a first capacitance signal, and the second sensing unit outputs a second capacitance signal; when the object to be detected passes through the second sensing unit, the second sensing unit outputs a first capacitance signal, and the first sensing unit outputs a second capacitance signal; the first capacitance signal is obtained based on the background signal background noise and the pollutant signal, and the second capacitance signal is obtained based on the background signal background noise; Performing differential processing on the first capacitance signal and the second capacitance signal to obtain a target signal, so as to suppress common-mode background noise; The target signal is displayed in real time through a computer program to detect pollutant particles and display differential noise reduction of the signal.
[0011] Optionally, performing differential processing on the first capacitance signal and the second capacitance signal to obtain a target signal includes: Determine the generation frequency of the voltage source and the modulation voltage of the demodulator; Determining a first capacitance and a first dielectric constant of a first sensing unit, and determining a second capacitance and a second dielectric constant of a second sensing unit; Determine a first current corresponding to the first capacitance signal according to the generation frequency, the modulation voltage of the demodulator, the first capacitance and the first dielectric constant, and determine a second current corresponding to the second capacitance signal according to the generation frequency, the modulation voltage of the demodulator, the second capacitance and the second dielectric constant; The target signal is obtained by performing differential processing on the first current and the second current.
[0012] Optionally, the method for determining the first capacitance and the second capacitance includes: determining an initial capacitance of the first sensing unit and the second sensing unit; Determining a first variation factor caused by the background noise and a second variation factor caused by a pollutant signal; The first capacitance is obtained according to the initial capacitance, the first variation factor, and the second variation factor, and the second capacitance is obtained according to the initial capacitance and the second variation factor.
[0013] Optionally, the method for determining the first current and the second current includes: Determine a first facing area of the first electrode plate and the second electrode plate, a first electrode plate distance, and a first dielectric change rate of the first dielectric constant; determine a second facing area of the first electrode plate and the third electrode plate, a second electrode plate distance, and a second dielectric change rate of the second dielectric constant; According to the first facing area, the first plate spacing, the first dielectric change rate and the electrostatic force constant, a first capacitance change rate of the first sensing unit is obtained; according to the second facing area, the second plate spacing, the second dielectric change rate and the electrostatic force constant, a second capacitance change rate of the second sensing unit is obtained; The first current is determined according to the modulation voltage, the generation frequency and the first capacitance change rate; the second current is determined according to the modulation voltage, the generation frequency and the second capacitance change rate.
[0014] In a third aspect, the present application provides an electronic device comprising: at least one memory for storing programs; and at least one processor for executing the programs stored in the memory. When the program stored in the memory is executed, the processor is used to execute the method described in the first aspect or any possible implementation of the first aspect.
[0015] In a fourth aspect, the present application provides a computer-readable storage medium, which stores a computer program. When the computer program runs on a processor, the processor executes the method described in the first aspect or any possible implementation of the first aspect.
[0016] In a fifth aspect, the present application provides a computer program product. When the computer program product runs on a processor, the processor executes the method described in the first aspect or any possible implementation of the first aspect.
[0017] It can be understood that the beneficial effects of the second to fifth aspects mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here.
[0018] In general, the above technical solutions conceived by this application have the following beneficial effects compared with the prior art: (1) The present application can effectively eliminate the common-mode components of the first capacitance signal and the second capacitance signal by performing differential processing on the first capacitance signal and the second capacitance signal, thereby helping to reduce the impact of external noise on the detection results, effectively eliminating the common-mode background noise, and making the target signal more accurate, thereby improving the detection accuracy of pollutant particles.
[0019] (2) With the support of computer programs, this application can display the processed target signal in real time, realize real-time detection of pollutant particles, and facilitate users to grasp the detection results of pollutants in a timely manner, so as to facilitate rapid response and decision-making.
[0020] (3) The sensor probe of the present application has a simple structure, low cost, and is easy to integrate, and has great prospects for popularization and application. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1This is one of the structural schematic diagrams of a particle detection system based on differential capacitance provided in an embodiment of the present application; Figure 2 This is the second structural schematic diagram of the differential capacitance-based particle detection system provided in the embodiment of the present application; Figure 3 This is one of the flow charts of the differential capacitance-based particle detection system provided in the embodiments of the present application.
[0022] Throughout the drawings, the same reference numerals are used to denote the same elements or structures, wherein: 110 is a sensor probe module; 120 is a sensor circuit module; 130 is a display module; 1 is the object to be detected; 2 is the first electrode plate; 3 is the second electrode plate; 4 is the third electrode plate; 5 is the front-end circuit; 6 is the amplifier circuit; 7 is the demodulator; 8 is the voltage source; and 9 is the computer. DETAILED DESCRIPTION
[0023] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.
[0024] The term "and / or" in this article is a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The symbol " / " in this article indicates that the associated objects are in an or relationship, for example, A / B means A or B.
[0025] The terms "first" and "second" in the specification and claims herein are used to distinguish different objects rather than to describe a specific order of the objects. For example, a first response message and a second response message are used to distinguish different response messages rather than to describe a specific order of the response messages.
[0026] In the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.
[0027] In the description of the embodiments of the present application, unless otherwise specified, "multiple" means two or more than two. For example, multiple processing units refer to two or more processing units, etc.; multiple elements refer to two or more elements, etc.
[0028] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application.
[0029] Reference Figure 1 , the present application provides a particle detection system based on differential capacitance, comprising: The sensor probe module 110 includes a first sensing unit and a second sensing unit. The object to be detected passes through the first sensing unit and the second sensing unit successively. When the object to be detected passes through the first sensing unit, the first sensing unit outputs a first capacitance signal, and the second sensing unit outputs a second capacitance signal; when the object to be detected passes through the second sensing unit, the second sensing unit outputs a first capacitance signal, and the first sensing unit outputs a second capacitance signal; the first capacitance signal is obtained based on background noise and a pollutant signal, and the second capacitance signal is obtained based on background noise; A sensing circuit module 120, connected to the first sensing unit and the second sensing unit, and configured to perform differential processing on the first capacitance signal and the second capacitance signal to obtain a target signal, so as to suppress common-mode background noise; The display module 130 is used to display the target signal in real time through a computer program to realize the detection of pollutant particles and the signal differential noise reduction display.
[0030] Reference Figure 2 , the sensor probe module includes a first electrode plate 2, a second electrode plate 3 and a third electrode plate 4; the length of the first electrode plate 2 is greater than that of the second electrode plate 3 and the third electrode plate 4; When the object 1 to be detected passes between the first electrode plate 2 and the second electrode plate 3, the first electrode plate 2 and the second electrode plate 3 obtain a first capacitance signal according to the background noise and the pollutant signal, and the first electrode plate 2 and the third electrode plate 4 obtain a second capacitance signal according to the background noise; When the object 1 to be detected passes between the first plate 2 and the third plate 4, the first plate 2 and the third plate 4 obtain a first capacitance signal according to the background noise and the pollutant signal, and the first plate 2 and the second plate 3 obtain a second capacitance signal according to the background noise.
[0031] Further, the sensing circuit module includes a front-end circuit 5, a demodulator 7 and a voltage source 8 connected in sequence; The front-end circuit 5 is connected to the second plate 3 and the third plate 4 respectively through a transformer, and the voltage source 8 is connected to the first plate 2; The front-end circuit 5 is used for performing differential processing on the first capacitance signal to obtain a differential signal to suppress common-mode background noise; The demodulator 7 is used to demodulate the differential signal to obtain the target signal and transmit it to the computer 9 of the display module; The voltage source 8 is used to provide voltage to the first electrode plate 2 and provide the required voltage input for the entire circuit.
[0032] Optionally, the sensing circuit module further includes an AC amplifier circuit 6, which is connected to the output end of the front-end circuit 5; the AC amplifier circuit 6 is used to amplify the differential signal to enhance the signal strength.
[0033] Specifically, the various modules of the differential capacitance-based particle detection system of the present application are described in detail below: The sensor probe module includes a first electrode plate, a second electrode plate and a third electrode plate, wherein the length of the first electrode plate is greater than that of the second electrode plate and the third electrode plate.
[0034] In this embodiment, the first electrode plate, the second electrode plate and the third electrode plate are all placed vertically, and the second electrode plate and the third electrode plate are adjacent to each other but not in contact.
[0035] The first sensing unit is composed of a first electrode plate and a second electrode plate, and the second sensing unit is composed of a first electrode plate and a third electrode plate; when the object to be detected passes between the first electrode plate and the second electrode plate, the first sensing unit generates a first capacitance signal based on background noise and pollutant signals, while the second sensing unit does not detect pollutant signals, only background noise, and generates a second capacitance signal.
[0036] In this process, the appearance of the object to be detected will cause the change of the capacitance between the plates, and due to the possible presence of pollutants, the capacitance signal will contain the comprehensive information of the pollutant signal and background noise.
[0037] Accordingly, when the object to be detected passes between the first electrode plate and the third electrode plate, the second sensing unit generates a first capacitance signal according to the background noise and the pollutant signal, while the first sensing unit does not detect the pollutant signal but only the background noise, and generates a second capacitance signal. The second capacitance signal mainly reflects the capacitance change under the influence of the background noise alone, because the detection process does not involve the additional influence of the pollutant at this time.
[0038] The sensing circuit module is connected to the first sensing unit and the second sensing unit through a transformer and is the core processing part of the entire detection system.
[0039] The front-end circuit is connected to the second plate and the third plate respectively through a transformer, and the voltage source is connected to the first plate. The main function of the front-end circuit is to perform differential processing on the first capacitance signal and the second capacitance signal obtained from the first sensing unit and the second sensing unit.
[0040] It should be noted that the embodiment of the present application utilizes the difference between the first capacitance signal and the second capacitance signal to eliminate the common mode background noise and obtain a differential signal. Because the first capacitance signal contains the pollutant signal and the background noise, and the second capacitance signal only contains the background noise, subtracting the two can highlight the pollutant signal and reduce the interference of the background noise.
[0041] The demodulator is connected to the front-end circuit, and its function is to demodulate the differential signal. Demodulation is the process of restoring the modulated signal to the original signal. The demodulator converts the differential signal into a target signal that can be directly recognized and processed by the display module.
[0042] The voltage source not only provides the required voltage for the first plate to ensure that an electric field is formed between the first plate and other plates so that capacitance detection can be realized, but also provides the necessary voltage input for the entire circuit to ensure the normal operation of the entire circuit.
[0043] Optionally, an AC amplifier circuit is connected to the output end of the front-end circuit to amplify the differential signal. In actual detection, since the differential signal obtained in some cases may be weak, the amplification function of the AC amplifier circuit can enhance the signal strength, making the subsequent processing and display clearer and more accurate. Finally, the target signal processed by the sensor circuit module is displayed in real time through a computer program.
[0044] The embodiment of the present application forms a sensing unit by combining different electrodes in the sensor probe module, utilizes the change in capacitance signal generated when the object to be detected passes by, and then undergoes differential processing, demodulation and possible signal amplification operations in the sensing circuit module, and finally displays the processed target signal in real time through the display module, thereby realizing the detection of pollutant particles and the signal differential noise reduction display function.
[0045] The sensor probe of the embodiment of the present application has a simple structure, low cost, and is easy to integrate, and has great prospects for promotion and application; differential capacitive sensing can suppress common-mode noise, greatly reduce the background noise level, and improve the signal-to-noise ratio of the sensor; real-time display of the sensor signal is achieved through a computer program, thereby realizing real-time detection of pollutant particles.
[0046] Reference Figure 3 The present application provides a particle detection method based on differential capacitance, comprising: S301. When the object to be detected passes through the first sensing unit, the first sensing unit outputs a first capacitance signal, and the second sensing unit outputs a second capacitance signal; when the object to be detected passes through the second sensing unit, the second sensing unit outputs a first capacitance signal, and the first sensing unit outputs a second capacitance signal; the first capacitance signal is obtained based on background noise and a pollutant signal, and the second capacitance signal is obtained based on background noise; S302. Perform differential processing on the first capacitance signal and the second capacitance signal to obtain a target signal to suppress common mode background noise; S303. Display the target signal in real time through a computer program to detect pollutant particles and display the signal differential noise reduction.
[0047] Specifically, in this embodiment, when the object to be detected flows through the sensor probe module in S301, the system starts to work. The sensor probe module includes a first sensing unit and a second sensing unit.
[0048] When the object to be detected passes by, it will interact with the surrounding environment. At the same time, due to the possible presence of pollutants, the electromagnetic environment in which the unit is located will change. The first sensing unit generates a first capacitance signal based on the background noise (the electromagnetic characteristics of the environment itself) and the pollutant signal (the impact of the pollutant on the electromagnetic environment). The first capacitance signal contains information about the interaction of the object to be detected, the pollutant, and the environment. The second sensing unit generates a second capacitance signal based on the background noise. (At this time, the object to be detected has not flowed through the second sensing unit, so there is no pollutant signal).
[0049] Similarly, when the object to be detected flows through the second sensing unit, this unit generates a first capacitance signal based on the pollutant signal and background noise. At this time, the first sensing unit only detects the background noise and generates a second capacitance signal based on the background noise. The second capacitance signal here mainly reflects the signal generated only by the environment (background) without the influence of pollutants, providing a reference benchmark for subsequent processing and helping to distinguish the signal changes actually caused by pollutants.
[0050] In step S302 , the first capacitance signal and the second capacitance signal are differentially processed.
[0051] Differential processing is a key step in this solution, and its purpose is to suppress common-mode background noise. Because the first capacitance signal contains comprehensive information about pollutants and background, while the second capacitance signal is mainly background noise, when the two are differentially operated, the background noise will offset each other to a certain extent, highlighting the impact of pollutants on the signal, thereby obtaining a target signal that better reflects the characteristics of pollutants. Through this processing method, the interference of background noise can be effectively reduced, making the subsequent detection of pollutants more accurate and reliable.
[0052] Finally, in step S303, the processed target signal is displayed in real time through a computer program, so that the user can find abnormal conditions in time during the detection process.
[0053] Optionally, performing differential processing on the first capacitance signal and the second capacitance signal to obtain a target signal includes: Determine the generation frequency of the voltage source and the modulation voltage of the demodulator; Determining a first capacitance and a first dielectric constant of a first sensing unit, and determining a second capacitance and a second dielectric constant of a second sensing unit; Determine a first current corresponding to the first capacitance signal according to the generation frequency, the modulation voltage of the demodulator, the first capacitance and the first dielectric constant, and determine a second current corresponding to the second capacitance signal according to the generation frequency, the modulation voltage of the demodulator, the second capacitance and the second dielectric constant; The target signal is obtained by performing differential processing on the first current and the second current.
[0054] Optionally, the method for determining the first capacitance and the second capacitance includes: determining an initial capacitance of the first sensing unit and the second sensing unit; Determining a first variation factor caused by the background noise and a second variation factor caused by a pollutant signal; The first capacitance is obtained according to the initial capacitance, the first variation factor, and the second variation factor, and the second capacitance is obtained according to the initial capacitance and the second variation factor.
[0055] Optionally, the method for determining the first current and the second current includes: Determine a first facing area of the first electrode plate and the second electrode plate, a first electrode plate distance, and a first dielectric change rate of the first dielectric constant; determine a second facing area of the first electrode plate and the third electrode plate, a second electrode plate distance, and a second dielectric change rate of the second dielectric constant; According to the first facing area, the first plate spacing, the first dielectric change rate and the electrostatic force constant, a first capacitance change rate of the first sensing unit is obtained; according to the second facing area, the second plate spacing, the second dielectric change rate and the electrostatic force constant, a second capacitance change rate of the second sensing unit is obtained; The first current is determined according to the modulation voltage, the generation frequency and the first capacitance change rate; the second current is determined according to the modulation voltage, the generation frequency and the second capacitance change rate.
[0056] Specifically, the current in the circuit When there is no disturbance, it can be expressed as: , (1) The voltage source generates a frequency of The modulation voltage is , , then the capacitance is The charge change at any time can be expressed as: (2) Substituting (2) into (1), we can obtain: .(3) When the contaminant to be detected enters between the plates, the dielectric constant between the plates will change, according to the capacitance between the plates (in It represents the area between the plates. Indicates the distance between the plates, represents the electrostatic force constant), (Capacitance change rate) can be expressed as: , (4) Combining (3) and (4): , (5) in, is the change in capacitance caused by the pollutant, that is, the dielectric change rate mentioned above. According to (5), it is not difficult to see that the traditional capacitive sensor relies on the difference in average dielectric constant caused by different materials between the plates, which causes the plate capacitance fluctuation to generate a current signal, and then detects oil pollution.
[0057] The differential capacitive sensor requires the establishment of two capacitive sensing probes of the same size and adjacent to each other. The object to be detected passes through the two units in turn. Similar to the above derivation process, assume that the first capacitance of the first sensing unit is , the corresponding first dielectric constant is , the first current in the circuit is ; Assume that the second capacitance of the second sensing unit is , the corresponding second dielectric constant is , the second current in the circuit is ,but and It can be expressed as: ,(6) .(7) use represents the capacitance change due to background noise, i.e. the first change factor, represents the capacitance change caused by contamination in the object to be detected, i.e. the second change factor, is the initial capacitance. When the pollutant just flows through the first sensor unit, the capacitances of the two sensor units can be expressed as: ,(8) .(9) Substituting (8) into (6) and (9) into (7), we can obtain the sensor current response: ,(10) .(11) The differential processing of the current signal can be obtained: .(12) From (12), it can be seen that the common mode background noise in the differential capacitive sensor is is suppressed, and at the same time For example, pollutant particles will only appear in one of the two sensing units, so only one capacitor's dielectric constant changes, while the other does not. The capacitance fluctuation signal will be collected by the circuit, processed and finally displayed on the computer. In general, differential capacitance sensing can effectively suppress common-mode background noise and improve the signal-to-noise ratio of the sensor.
[0058] It should be understood that the various numerical numbers involved in the embodiments of the present application are only used for the convenience of description and are not used to limit the scope of the embodiments of the present application.
[0059] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application shall be included in the scope of protection of the present application.
Claims
1. A particle detection system based on differential capacitance, characterized in that: include: The sensor probe module includes a first sensing unit and a second sensing unit, and the object to be detected passes through the first sensing unit and the second sensing unit successively; When the object to be detected passes through the first sensing unit, the first sensing unit outputs a first capacitance signal, and the second sensing unit outputs a second capacitance signal; when the object to be detected passes through the second sensing unit, the second sensing unit outputs a first capacitance signal, and the first sensing unit outputs a second capacitance signal; the first capacitance signal is obtained based on background noise and a pollutant signal, and the second capacitance signal is obtained based on background noise; A sensing circuit module, connected to the first sensing unit and the second sensing unit, and configured to perform differential processing on the first capacitance signal and the second capacitance signal to obtain a target signal so as to suppress common-mode background noise; The display module is used to display the target signal in real time through a computer program to realize the detection of pollutant particles and the signal differential noise reduction display.
2. The particle detection system based on differential capacitance according to claim 1, characterized in that: The sensor probe module includes a first electrode plate, a second electrode plate and a third electrode plate; the length of the first electrode plate is greater than that of the second electrode plate and the third electrode plate; The first electrode plate and the second electrode plate form a first sensing unit, and the first electrode plate and the third electrode plate form a second sensing unit; When the object to be detected passes between the first electrode plate and the second electrode plate, the first electrode plate and the second electrode plate obtain a first capacitance signal according to the background noise and the pollutant signal, and the first electrode plate and the third electrode plate obtain a second capacitance signal according to the background noise; When the object to be detected passes between the first plate and the third plate, the first plate and the third plate obtain a first capacitance signal according to the background noise and the pollutant signal, and the first plate and the second plate obtain a second capacitance signal according to the background noise.
3. The particle detection system based on differential capacitance according to claim 2, characterized in that: The sensing circuit module includes a front-end circuit, a demodulator and a voltage source connected in sequence; The front-end circuit is connected to the second plate and the third plate respectively through a transformer, and the voltage source is connected to the first plate; The front-end circuit is used to perform differential processing on the first capacitance signal to obtain a differential signal to suppress common-mode background noise; The demodulator is used to demodulate the differential signal to obtain the target signal and transmit it to the display module; The voltage source is used to provide voltage to the first electrode plate and provide the required voltage input for the entire circuit.
4. The particle detection system based on differential capacitance according to claim 3, characterized in that: The sensing circuit module also includes an AC amplifier circuit, which is connected to the output end of the front-end circuit; the AC amplifier circuit is used to amplify the differential signal to enhance the signal strength.
5. A differential capacitance-based particle detection method implemented by the differential capacitance-based particle detection system according to any one of claims 1 to 4, characterized in that: include: When the object to be detected passes through the first sensing unit, the first sensing unit outputs a first capacitance signal, and the second sensing unit outputs a second capacitance signal; When the object to be detected passes through the second sensing unit, the second sensing unit outputs a first capacitance signal, and the first sensing unit outputs a second capacitance signal; the first capacitance signal is obtained based on background noise and a pollutant signal, and the second capacitance signal is obtained based on background noise; Performing differential processing on the first capacitance signal and the second capacitance signal to obtain a target signal, so as to suppress common-mode background noise; The target signal is displayed in real time through a computer program to detect pollutant particles and display differential noise reduction of the signal.
6. The particle detection method based on differential capacitance according to claim 5, characterized in that: Performing differential processing on the first capacitance signal and the second capacitance signal to obtain a target signal includes: Determine the generation frequency of the voltage source and the modulation voltage of the demodulator; Determining a first capacitance and a first dielectric constant of a first sensing unit, and determining a second capacitance and a second dielectric constant of a second sensing unit; Determine a first current corresponding to the first capacitance signal according to the generation frequency, the modulation voltage of the demodulator, the first capacitance and the first dielectric constant, and determine a second current corresponding to the second capacitance signal according to the generation frequency, the modulation voltage of the demodulator, the second capacitance and the second dielectric constant; The target signal is obtained by performing differential processing on the first current and the second current.
7. The particle detection method based on differential capacitance according to claim 5, characterized in that: The method for determining the first capacitance and the second capacitance includes: determining an initial capacitance of the first sensing unit and the second sensing unit; Determining a first variation factor caused by the background noise and a second variation factor caused by a pollutant signal; The first capacitance is obtained according to the initial capacitance, the first variation factor, and the second variation factor, and the second capacitance is obtained according to the initial capacitance and the second variation factor.
8. The particle detection method based on differential capacitance according to claim 6, characterized in that: The method for determining the first current and the second current includes: Determine a first facing area of the first electrode plate and the second electrode plate, a first electrode plate distance, and a first dielectric change rate of the first dielectric constant; determine a second facing area of the first electrode plate and the third electrode plate, a second electrode plate distance, and a second dielectric change rate of the second dielectric constant; According to the first facing area, the first plate spacing, the first dielectric change rate and the electrostatic force constant, a first capacitance change rate of the first sensing unit is obtained; according to the second facing area, the second plate spacing, the second dielectric change rate and the electrostatic force constant, a second capacitance change rate of the second sensing unit is obtained; The first current is determined according to the modulation voltage, the generation frequency and the first capacitance change rate; the second current is determined according to the modulation voltage, the generation frequency and the second capacitance change rate.
9. An electronic device, characterized in that: include: at least one memory for storing a computer program; At least one processor is used to execute the program stored in the memory. When the program stored in the memory is executed, the processor is used to execute the method according to any one of claims 5 to 8.
10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program runs on a processor, the processor is caused to execute the method according to any one of claims 5 to 8.