High-sensitivity differential pressure ceramic capacitive sensor based on double electrodes and measuring method thereof

Abstract

The invention discloses a dual-electrode-based high-sensitivity differential pressure ceramic capacitive sensor and a measurement method thereof, and belongs to the technical field of pressure sensors. The sensor comprises a ceramic substrate, a dual-electrode structure, a differential pressure sensitive diaphragm and a signal processing module. The two electrodes are symmetrically distributed on the two sides of the diaphragm, when the diaphragm is subjected to the differential pressure effect on the two sides, capacitance changes reversely, high-sensitivity detection of the differential pressure is achieved through a differential calculation formula, and the sensitivity is improved by two times compared with a single electrode. And the ceramic plate integrates an overvoltage protection function, so that the diaphragm is prevented from over-limit deformation. The design solves the problems that a traditional sensor is low in sensitivity and weak in interference resistance in tiny differential pressure detection, and can be widely applied to the fields of industrial pressure monitoring, automobile differential pressure control, new energy battery thermal management and the like. And the reliability and the precision are remarkably improved by a dual-electrode differential structure and an overvoltage protection mechanism, and an innovative scheme is provided for the design of a high-cost-performance capacitor core body.

Description

Technical Field

[0001] The present invention relates to the technical field of pressure sensors, and particularly to a high-sensitivity differential pressure ceramic capacitive sensor based on a dual electrode and a measurement method thereof. Background Art

[0002] In recent years, ceramic capacitive sensors have been widely used in the fields of industrial automation, automotive electronics, and new energy due to their characteristics such as high temperature resistance, corrosion resistance, and good long-term stability. Traditional ceramic capacitive pressure sensors mostly adopt a single electrode structure, and the electrode gap is changed by the deformation of the diaphragm under pressure, and then the capacitance change is detected. However, such a design has the following significant defects:

[0003] 1. Limited sensitivity: The sensitivity of a single electrode sensor is inversely proportional to the initial gap d0. To improve the sensitivity, d0 needs to be reduced, but it is difficult to achieve high-precision detection of small pressure differences (such as <1 kPa) due to processing accuracy and breakdown voltage limitations. For example, a Chinese patent proposed a thick film ceramic pressure sensor, but its linear error is still as high as ±0.5% FS, which is difficult to meet the requirements of high-precision scenarios.

[0004] 2. Weak anti-interference ability: Single capacitance measurement is easily affected by environmental factors such as temperature drift and electromagnetic noise, resulting in zero drift. The literature "Design of a Construction Site Safety Management System Based on the Internet of Things" in 2022 pointed out that the temperature drift coefficient of existing sensors generally exceeds 0.05% / °C under complex working conditions, affecting long-term stability.

[0005] 3. Lack of overpressure protection mechanism: Traditional sensors are easily damaged due to excessive deformation of the diaphragm under high pressure or impact loads. For example, a Chinese patent proposed to prevent overload by the diaphragm abutting against the base, but this passive protection method cannot dynamically limit the deformation and will sacrifice sensitivity.

[0006] 4. Single measurement algorithm: Existing technologies mostly rely on fixed calibration parameters and are difficult to adapt to multi-range or dynamic working conditions. Although the publicly disclosed technology "Intelligent Pipe Network Monitoring System" in 2023 introduced a data fusion algorithm, it did not solve the problem of real-time dynamic compensation of capacitance values.

[0007] In view of the above problems, the present invention proposes a differential pressure ceramic capacitive sensor based on a dual electrode structure and a measurement method. Through dual electrode differential design, overpressure protection integration, and dynamic calibration algorithm, the sensitivity and reliability are significantly improved, filling the gap in the existing technology. Summary of the Invention

[0008] In view of the existing problems described above, the present invention is proposed.

[0009] Therefore, the present invention provides a high-sensitivity differential pressure ceramic capacitive sensor based on a dual-electrode and its measurement method to solve the problem of detecting the change of the capacitive core body that maintains high sensitivity and stability in a complex environment.

[0010] To solve the above technical problems, the present invention provides the following technical solutions:

[0011] In a first aspect, the present invention provides a high-sensitivity differential pressure ceramic capacitive sensor based on a dual-electrode, which includes,

[0012] A ceramic substrate (1), a first ceramic plate (1a) and a second ceramic plate (2a) fixed on both sides of the substrate;

[0013] A differential pressure sensitive diaphragm (3), located between the two ceramic plates, deforming under the action of pressures (P1, P2) on both sides;

[0014] A dual-electrode structure, including a first capacitor (C1) and a second capacitor (C2) symmetrically distributed on both sides of the diaphragm, wherein the deformation of the diaphragm causes the gap d1 of C1 = d0 - Δd, the gap d2 of C2 = d0 + Δd, and Δd is the displacement of the diaphragm;

[0015] A signal processing module, based on the formula

[0016]

[0017] Outputs the differential pressure measurement value, where C date Is the final capacitance measurement value, CCP and CCN are the zero compensation internal capacitance values of C1 and C2 respectively, and K range Is the range coefficient.

[0018] As a preferred solution of the high-sensitivity differential pressure ceramic capacitive sensor based on a dual-electrode of the present invention, wherein: the second ceramic plate (2a) has an overvoltage protection function. When the deformation of the diaphragm exceeds the threshold, the second ceramic plate contacts the diaphragm to limit further deformation and prevent breakdown.

[0019] As a preferred solution of the high-sensitivity differential pressure ceramic capacitive sensor based on a dual-electrode of the present invention, wherein: the sensitivity of the dual-electrode structure is 2 times that of the single-electrode structure, satisfying the relationship

[0020]

[0021] Where d0 is the initial gap, and Δd << d0.

[0022] As a preferred solution of the high-sensitivity differential pressure ceramic capacitive sensor based on a dual-electrode of the present invention, wherein: the signal processing module dynamically calibrates the values of CCP and CCN to satisfy

[0023]

[0024] To eliminate zero drift.

[0025] As a preferred embodiment of the high-sensitivity differential pressure ceramic capacitive sensor based on dual electrodes according to the present invention, wherein: the linear error of the sensor is ≤ ±0.25% FS, the temperature drift coefficient is ≤ 0.02% / °C, and it is applicable to the temperature range of -40°C to 150°C; the deformation amount Δd of the diaphragm (3) satisfies Δd / d0 ≤ 0.1 to ensure linear response; the ceramic substrate (1) and the ceramic plates (1a, 2a) are made of alumina ceramic material, and the dielectric strength is ≥ 15 kV / mm.

[0026] As a preferred embodiment of the measurement method of a differential pressure ceramic capacitive sensor based on dual electrodes according to the present invention, it includes the following steps:

[0027] S1. Collect the dual-electrode capacitance values C1 and C2;

[0028] S2. Calculate the compensation capacitances CCP and CCN according to the preset K range value;

[0029] S3. Output the differential pressure measurement value through the differential formula ;

[0030] S4. When C date exceeds the range of [-223, 223 - 1], trigger the overvoltage protection mechanism.

[0031] As a preferred embodiment of the high-sensitivity differential pressure ceramic capacitive sensor based on dual electrodes and its measurement method according to the present invention, wherein: the value range of K range is 1 to 8, and multi-range switching is achieved by adjusting K range .

[0032] As a preferred embodiment of the high-sensitivity differential pressure ceramic capacitive sensor based on dual electrodes and its measurement method according to the present invention, wherein: the sensor is applied to the monitoring of the intake / exhaust differential pressure of an automotive engine, the differential pressure feedback of an industrial pipeline, or the differential pressure control of a new energy battery thermal management system.

[0033] In a second aspect, the present invention provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and wherein: when the computer program is executed by the processor, it implements any step of the high-sensitivity differential pressure ceramic capacitive sensor based on dual electrodes and its measurement method as described in the first aspect of the present invention.

[0034] In a third aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein: when the computer program is executed by a processor, it implements any step of the high-sensitivity differential pressure ceramic capacitor sensor based on two electrodes and its measurement method as described in the first aspect of the present invention.

[0035] The beneficial effects of the present invention are as follows: the present invention adopts a dual-electrode differential design (C1 and C2 change in opposite directions), and the sensitivity is twice that of a single-electrode structure, which can detect tiny pressure differences and is suitable for high-precision scenarios. The zero-point drift is compensated by a dynamic calibration algorithm (CCP and CCN values are adjusted in real time), and combined with the temperature compensation mechanism, the temperature drift coefficient is ≤0.02% / ℃, which is more than 60% higher than that of traditional sensors (>0.05% / ℃). The second ceramic plate overvoltage protection mechanism is integrated. When the diaphragm deformation Δd exceeds the threshold (Δd_max), the displacement is automatically limited to avoid breakdown or permanent deformation, and the sensor life is extended by more than 30%. Common-mode interference is eliminated based on the differential formula, and the linear error is ≤±0.25%FS, which is 50% higher than the accuracy of the existing technology (±0.5%FS). The alumina ceramic matrix and the temperature compensation algorithm work together to support stable operation in a wide temperature range of -40℃ to 150℃, meeting the needs of extreme environments (such as automobile engine compartments and industrial high-temperature pipelines). By adjusting the range coefficient, fast switching between multiple ranges can be achieved to adapt to different pressure difference detection scenarios and reduce hardware redundancy costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0037] Figure 1 Schematic diagram comparing the conventional core and the pressure difference core in Example 1.

[0038] Figure 2 Schematic diagram of the process of the high-sensitivity differential pressure ceramic capacitor sensor based on two electrodes and its measurement method in Example 1. DETAILED DESCRIPTION

[0039] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0040] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0041] Secondly, the so-called "one embodiment" or "embodiment" herein refers to a specific feature, structure or characteristic that may be included in at least one implementation manner of the present invention. The appearances of "in one embodiment" in different places in this specification do not all refer to the same embodiment, nor are they separate or alternative embodiments that are mutually exclusive with other embodiments.

[0042] Embodiment 1, referring to Figures 1 to 2 , is the first embodiment of the present invention. This embodiment provides a high-sensitivity differential pressure ceramic capacitive sensor based on a dual electrode and its measurement method, including,

[0043] A ceramic substrate (1), a first ceramic plate (1a) and a second ceramic plate (2a) fixed on both sides of the substrate;

[0044] A differential pressure sensitive diaphragm (3), located between the two ceramic plates, deforms under the action of pressures (P1, P2) on both sides;

[0045] A dual electrode structure, including a first capacitor (C1) and a second capacitor (C2) symmetrically distributed on both sides of the diaphragm. Among them, the deformation of the diaphragm causes the gap d1 of C1 = d0 - Δd, and the gap d2 of C2 = d0 + Δd, where Δd is the displacement of the diaphragm;

[0046] A signal processing module, based on the formula

[0047]

[0048] Outputs the differential pressure measurement value, where C date is the final capacitance measurement value, CCP and CCN are the zero compensation internal capacitance values of C1 and C2 respectively, and K range is the range coefficient.

[0049] The second ceramic plate (2a) has an overpressure protection function. When the deformation of the diaphragm exceeds the threshold, the second ceramic plate contacts the diaphragm to limit further deformation and prevent breakdown.

[0050] The sensitivity of the dual electrode structure is 2 times that of the single electrode structure, satisfying the relationship

[0051]

[0052] where d0 is the initial gap, and Δd << d0.

[0053] The signal processing module dynamically calibrates the values of CCP and CCN to satisfy

[0054]

[0055] To eliminate zero drift.

[0056] The linear error of the sensor is ≤ ±0.25% FS, the temperature drift coefficient is ≤ 0.02% / °C, and it is applicable to the temperature range of -40°C to 150°C; the deformation amount Δd of the diaphragm (3) satisfies Δd / d0 ≤ 0.1 to ensure linear response; the ceramic substrate (1) and the ceramic plates (1a, 2a) are made of alumina ceramic material, and the dielectric strength is ≥ 15 kV / mm.

[0057] A high-sensitivity differential pressure ceramic capacitive sensor based on a dual electrode and its measurement method, comprising the following steps:

[0058] S1. Collect the dual electrode capacitance values C1 and C2; specifically,

[0059] The capacitance values C1 and C2 of the dual electrode structure are collected in real time through a capacitance digital converter (CDC), where:

[0060] C1 is the capacitance value corresponding to the reduction of the gap (d1 = d0 - △d) after the diaphragm is affected by the pressure difference;

[0061] C2 is the capacitance value corresponding to the increase of the gap (d2 = d0 + △d) after the diaphragm is affected by the pressure difference;

[0062] The sampling frequency is ≥ 100 Hz to ensure the requirements for dynamic pressure detection.

[0063] S2. Calculate the compensation capacitances CCP and CCN according to the preset K range value; specifically,

[0064] According to the preset range coefficient K range (value range 1 to 8), dynamically calibrate the zero compensation capacitance according to the formula:

[0065]

[0066] Example: When K range = 2 and C1 = 0.28 pF, CCP = 0.28 / (2 × 0.07) = 2.

[0067] S3. Output the differential pressure measurement value through the differential formula ; specifically,

[0068] Substitute C1, C2, CCP, and CCN into the differential formula:

[0069]

[0070] The output result C date ∈[-223, 223 - 1], and is directly mapped to the differential pressure physical quantity (e.g., -223 corresponds to the minimum differential pressure, 223 - 1 corresponds to the maximum differential pressure).

[0071] S4. When Cdate When it exceeds the range of [-223, 223 - 1], the overvoltage protection mechanism is triggered. Specifically,

[0072] When C date exceeds the range of [-223, 223 - 1], it is determined as an overvoltage state, and the following actions are performed:

[0073] Cut off the excitation power supply through the control circuit and stop the capacitor acquisition;

[0074] Trigger the mechanical limit function of the second ceramic plate (2a) to make the diaphragm contact the ceramic plate, restricting the deformation amount △d ≦ △d max ;

[0075] Send an alarm signal (such as audible and visual alarm or remote notification) to the terminal device.

[0076] Dynamic calibration: The real-time calculation of CCP and CCN in step S2 eliminates zero drift and adapts to temperature changes (such as -40°C to 150°C);

[0077] K range has a value range of 1 to 8. By adjusting K range multi-range switching is achieved.

[0078] Specifically, multi-range adaptation: By adjusting K range the range is switched. For example, K range = 1 corresponds to 0 to 10 kPa, and K range = 8 corresponds to 0 to 1.25 kPa;

[0079] K range The selection is shown in Table 1:

[0080]

[0081] Table 1: Selection values of K range

[0082] Overvoltage protection linkage: Step S4 combines electronic protection (power-off) and mechanical protection (limitation) to ensure the safety and durability of the sensor under over-limit pressure.

[0083] The specific design and manufacturing of the double-electrode structure are specifically

[0084] Electrode layout:

[0085] Inside the ceramic substrate (1), the first electrode (C1) and the second electrode (C2) adopt a symmetric annular design, surrounding the central axis of the differential pressure sensitive diaphragm (3) to ensure uniform deformation under the action of differential pressure.

[0086] ​The electrode material is selected as gold or platinum and deposited on the surface of the ceramic plates (1a, 2a) through a thick-film printing process, with a thickness ≤ 10 μm and a resistivity ≤ 0.1 Ω·cm.

[0087] Initial gap control:

[0088] The initial gap d0 is designed to be 50 μm. Through a laser fine-tuning process, the machining error is ensured to be ≤ ±1 μm, meeting the requirement of sensitivity K ≈ 2 / d0 = 0.04 / μm.

[0089] The diaphragm (3) is made of silicon nitride ceramic material with a thickness of 0.2 mm and a flexural strength ≥ 800 MPa to ensure effective deformation under a small pressure difference (such as 0.1 kPa).

[0090] Implementation details of the overpressure protection mechanism, specifically,

[0091] Mechanical limit design:

[0092] A convex structure is set on the surface of the second ceramic plate (2a) with a height of Δd max = 5 μm. When the deformation amount Δd of the diaphragm exceeds this threshold, the diaphragm contacts the convex to prevent further displacement.

[0093] The material of the convex structure is the same as that of the ceramic plate, and the surface is polished (roughness Ra ≤ 0.1 μm) to avoid scratching the diaphragm during contact.

[0094] Electronic protection linkage:

[0095] When C date exceeds the limit, the control circuit immediately cuts off the excitation voltage (typical value 5V) and disconnects the signal acquisition circuit through the MOSFET switch to prevent overload damage.

[0096] The alarm signal is output to the host computer through the CAN bus or RS-485 interface, supporting custom alarm thresholds (such as triggered by -230 or 230).

[0097] Dynamic calibration and temperature compensation are achieved, specifically,

[0098] Zero-point compensation algorithm:

[0099] In the sensor initialization stage, the C1 and C2 values in the state of no pressure difference are collected, and the initial

[0100]

[0101] is calculated and stored in the EEPROM.

[0102] Real-time temperature detection: An integrated DS18B20 temperature sensor updates the ambient temperature T every 10 ms, and corrects CCP and CCN according to the temperature drift coefficient:

[0103] CCP 修正 =CCP0×(1 + α(T - T0)), α = 0.02% / °C

[0104] Multi - range switching (Krange = 1 - 8):

[0105] Krange Range (kPa) Resolution (Pa) 1 0～10 45 2 0～5 22 ... ... ... 8 0～1.25 5.6

[0106] Table 2: Range configuration table

[0107] Receive external instructions through the SPI interface to switch Krange and dynamically adjust the CCP and CCN calculation parameters.

[0108] Linearity and temperature drift test verification, specifically,

[0109] Linearity test:

[0110] Use a standard pressure source (accuracy ±0.05% FS) to pressurize at 10% intervals within the range and record the C date output value and calculate the linear error:

[0111]

[0112] Temperature drift test:

[0113] Place the sensor in a high - low temperature chamber (-40°C to 150°C), keep it at a constant temperature for 1 hour at every 10°C interval, and record the zero - point offset:[[]]

[0114]

[0115] The sensor is applied to monitor the intake / exhaust pressure difference of automotive engines, pressure difference feedback in industrial pipelines, or pressure difference control in the thermal management system of new energy batteries.

[0116] Implementation examples of application scenarios, specifically,[[]]

[0117] Automotive engine pressure difference monitoring:

[0118] Installed between the intake manifold and the exhaust manifold of the engine to detect the pressure difference in real - time (range 0 - 5 kPa, K range = 2), and control the speed of the turbocharger through the ECU to improve combustion efficiency.

[0119] Data sampling rate 1 kHz, response time ≤1 ms, meeting the requirements of dynamic working conditions.

[0120] New energy battery thermal management:

[0121] Integrated into the liquid - cooling system pipeline to detect the pressure difference between the inlet and outlet of the coolant (range 0 - 2 kPa, K range= 4), combined with the PID algorithm to adjust the pump speed to ensure the uniformity of battery temperature (temperature control accuracy ±1°C).

[0122] Ceramic materials and process requirements, specifically,

[0123] Ceramic substrate (1) and ceramic plates (1a, 2a):

[0124] Material: 96% alumina ceramic, dielectric strength ≥15 kV / mm, thermal expansion coefficient 7.2×10 -6 / °C;

[0125] Processing technology: isostatic pressing and then high-temperature sintering (1600°C), and the surface metallized area forms electrodes through screen printing and sintering.

[0126] Bonding process of the diaphragm (3):

[0127] Adopt glass paste sealing technology to vacuum bond the diaphragm and the ceramic plate at 850°C, and the airtightness ≤1×10 - 8 Pa·m 3 / s to ensure long-term stability.

[0128] Hardware design of the signal processing module, specifically,

[0129] Core chip:

[0130] Capacitance digital converter (CDC): Select AD7745, resolution 24 bit, supporting differential input (C1, C2);

[0131] Microcontroller: STM32F407, with a built-in floating-point operation unit to perform differential formula calculations in real time.

[0132] Anti-interference design:

[0133] The signal traces use shielded twisted pair wires, and the PCB layout isolates the analog and digital areas;

[0134] Software filtering: Moving average filtering (window width 10 points) combined with an IIR low-pass filter (cutoff frequency 50 Hz).

[0135] This embodiment also provides a computer device, applicable to the case of a high-sensitivity differential pressure ceramic capacitive sensor based on dual electrodes and its measurement method, including: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions to implement the high-sensitivity differential pressure ceramic capacitive sensor based on dual electrodes and its measurement method as proposed in the above embodiment.

[0136] The computer device may be a terminal, and the computer device includes a processor, a memory, a communication interface, a display screen, and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be implemented through WIFI, a carrier network, NFC (Near Field Communication), or other technologies. The display screen of the computer device may be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device may be a touch layer covering the display screen, or may also be a button, a trackball, or a touchpad provided on the housing of the computer device, or may also be an external keyboard, touchpad, or mouse, etc.

[0137] This embodiment also provides a storage medium, on which a computer program is stored, and when the program is executed by a processor, it implements the high-sensitivity differential pressure ceramic capacitive sensor based on dual electrodes and its measurement method proposed in the above embodiment; the storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM for short), Electrically Erasable Programmable Read-Only Memory (EEPROM for short), Erasable Programmable Read Only Memory (EPROM for short), Programmable Red-Only Memory (PROM for short), Read-Only Memory (ROM for short), magnetic memory, flash memory, a magnetic disk, or an optical disc.

[0138] In summary, the present invention adopts a dual-electrode differential design (C1 and C2 change in opposite directions), and its sensitivity is twice that of a single-electrode structure. It can detect tiny pressure differences and is suitable for high-precision scenarios. The zero-point drift is compensated by a dynamic calibration algorithm (CCP and CCN values are adjusted in real time). Combined with the temperature compensation mechanism, the temperature drift coefficient is ≤0.02% / ℃, which is more than 60% higher than that of traditional sensors (>0.05% / ℃). The second ceramic plate overvoltage protection mechanism is integrated. When the diaphragm deformation Δd exceeds the threshold (Δd_max), the displacement is automatically limited to avoid breakdown or permanent deformation, and the sensor life is extended by more than 30%. Common-mode interference is eliminated based on the differential formula, and the linear error is ≤±0.25%FS, which is 50% higher than the accuracy of the existing technology (±0.5%FS). The alumina ceramic matrix and the temperature compensation algorithm work together to support stable operation in a wide temperature range of -40℃ to 150℃, meeting the needs of extreme environments (such as automobile engine compartments and industrial high-temperature pipelines). By adjusting the range coefficient, fast switching between multiple ranges can be achieved to adapt to different pressure difference detection scenarios and reduce hardware redundancy costs.

[0139] 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 the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A high-sensitivity differential pressure ceramic capacitor sensor based on a dual electrode, characterized in that, Comprising: A ceramic substrate (1), a first ceramic plate (1a) and a second ceramic plate (2a) fixed to both sides of the substrate; A differential pressure sensitive diaphragm (3), located between the two ceramic plates, deforming under the action of pressures (P1, P2) on both sides; A dual - electrode structure, including a first capacitor (C1) and a second capacitor (C2) symmetrically distributed on both sides of the diaphragm. Among them, the deformation of the diaphragm causes the gap d1 of C1 = d0 - Δd, and the gap d2 of C2 = d0 + Δd, where Δd is the displacement of the diaphragm; A signal processing module, based on the formula Output differential pressure measurement value, where C date is the final capacitance measurement value, CCP and CCN are the zero compensation internal capacitance values of C1 and C2 respectively, and K range is the range coefficient.

2. The high-sensitivity differential pressure ceramic capacitor sensor based on a dual electrode according to claim 1, characterized in that: The second ceramic plate (2a) has an over - voltage protection function. When the deformation of the diaphragm exceeds the threshold, the second ceramic plate contacts the diaphragm to limit further deformation and prevent breakdown.

3. The high-sensitivity differential pressure ceramic capacitive sensor based on dual electrodes according to claim 1, characterized in that: The sensitivity of the dual - electrode structure is 2 times that of the single - electrode structure, satisfying the relational expression where d is the initial gap and Δd << d0.

4. The high-sensitivity differential pressure ceramic capacitive sensor based on dual electrodes according to claim 1, characterized in that: The signal processing module calibrates the values of CCP and CCN dynamically to satisfy To eliminate zero - point drift.

5. The high-sensitivity differential pressure ceramic capacitive sensor based on dual electrodes according to claim 1, characterized in that: The linear error of the sensor is ≤ ±0.25% FS, the temperature drift coefficient is ≤ 0.02% / °C, and it is applicable to the temperature range of - 40°C to 150°C; the deformation amount Δd of the diaphragm (3) satisfies Δd / d0 ≤ 0.1 to ensure linear response; the ceramic substrate (1) and the ceramic plates (1a, 2a) are made of alumina ceramic material, and the dielectric strength is ≥ 15 kV / mm.

6. A measurement method based on a dual - electrode differential pressure ceramic capacitor sensor, characterized in that, Including the following steps: S1. Collect the dual - electrode capacitance values C1, C2; S2. Calculate compensation capacitors CCP and CCN according to a preset K range value; S3. Output the measured differential pressure value through the differential formula Output the measured differential pressure value; S4. When C date exceeds the range of [-223, 223 - 1], the overvoltage protection mechanism is triggered.

7. The high-sensitivity differential pressure ceramic capacitive sensor based on double electrodes and its measurement method according to claim 6, characterized in that: The said K range has a value range of 1 to 8, and by adjusting K range multi-range switching is achieved.

8. The high-sensitivity differential pressure ceramic capacitive sensor based on dual electrodes and its measurement method according to claim 1 or 6, characterized in that: The sensor is applied to the monitoring of the intake / exhaust pressure difference of an automotive engine, the pressure difference feedback of an industrial pipeline, or the pressure difference control of a new - energy battery thermal management system.

9. A computer device, comprising a memory and a processor, the memory storing a computer program, characterized in that: When the processor executes the computer program, it implements the steps of the dual - electrode - based high - sensitivity differential - pressure ceramic capacitive sensor and its measurement method according to any one of claims 1 to 8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by the processor, it implements the steps of the dual - electrode - based high - sensitivity differential - pressure ceramic capacitive sensor and its measurement method according to any one of claims 1 to 8.

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