Temperature compensation type ocean pressure sensor calibration device and method

Abstract

The invention belongs to the field of ocean instrument metering calibration, and particularly relates to a temperature compensation type ocean pressure sensor calibration device and method, and the device comprises a standard constant temperature system, a standard constant pressure system, a data collection system, and a data processing unit. The standard constant temperature system is used for providing a controllable and monitorable constant temperature environment for the calibrated sensor; the standard constant pressure system is used for providing a controllable standard pressure source; the data acquisition system synchronously acquires temperature, standard pressure and sensor output signals; and the data processing unit establishes a temperature-pressure mathematical relationship model based on the acquired data and generates temperature compensation correction parameters. According to the calibration method, a plurality of standard pressures are applied at different temperature points, synchronous data are acquired, and a temperature compensation function is obtained through fitting by using a least square method, so that high-precision compensation of the ocean pressure sensor in a wide temperature gradient environment is realized. The measurement precision of the ocean pressure sensor in the temperature range is effectively improved, and the method is suitable for high-precision scenes such as ocean hydrological observation.

Description

Technical Field

[0001] This invention belongs to the field of marine instrumentation and calibration, specifically a temperature-compensated marine pressure sensor calibration device and method. Background Technology

[0002] As a core sensitive component in fields such as marine hydrological observation, marine oil and gas resource exploration, and deep-sea exploration, the measurement accuracy of marine pressure sensors directly determines the reliability of the acquired marine data. In practical marine applications, sensors need to operate for extended periods in harsh environments with wide temperature gradients and high hydrostatic pressure, and temperature changes are one of the key interference factors affecting their measurement accuracy.

[0003] In existing technologies, the calibration of marine pressure sensors mainly adopts the conventional static pressure calibration method, which lacks detailed calibration methods for the influence of temperature changes. The national verification standard JJG763-2019, "Temperature, Salinity, and Depth Measurement Instruments," only mentions that pressure sensors with temperature compensation functions need to be placed in a constant temperature chamber for compensation verification, without describing detailed calibration methods. Static pressure calibration involves applying a fixed pressure from a standard pressure source and comparing the deviation between the sensor output value and the standard value to complete the calibration. The above calibration methods have certain shortcomings: calibration is performed under constant temperature conditions, failing to fully consider the impact of temperature changes on the sensor, or employing only a simple single-point temperature compensation strategy.

[0004] From the perspective of sensor working mechanism, the material properties of its sensitive elements (such as piezoresistive silicon diaphragms, fiber Bragg grating sensitive structures, etc.) change significantly with temperature. In the deep-sea environment, water temperature can drop from above 35°C at the surface to 0°C or even -1°C at the deep sea. This huge temperature gradient can cause the measurement error of uncompensated pressure sensors to reach 1%~2% FS (full scale), which is far from meeting the accuracy requirements of less than 0.1% FS for scenarios such as marine hydrological monitoring and high-precision underwater navigation. Therefore, developing a temperature-compensated marine pressure sensor calibration method to achieve a dual improvement in calibration accuracy and field applicability has become an urgent technical challenge in the field of marine instrumentation. Summary of the Invention

[0005] The purpose of this invention is to provide a temperature-compensated marine pressure sensor calibration device and method, addressing the current situation where most existing technologies calibrate marine pressure sensors under single-point temperature conditions. This invention supplements the existing methods with multi-point temperature compensation calibration, thereby improving the calibration accuracy of marine pressure sensors. The technical solution employed in this invention utilizes a standard constant pressure system combined with a standard constant temperature system and a temperature-pressure mathematical compensation model to complete multi-point temperature compensation calibration. A temperature-compensated marine pressure sensor calibration method includes preparatory work, a standard constant temperature system, a standard constant pressure system, a data acquisition system, data processing, and a mathematical compensation model.

[0006] The technical solution adopted by the present invention to achieve the above objectives is: a temperature-compensated marine pressure sensor calibration device, characterized in that it includes: a standard constant temperature system, a standard constant pressure system, a data acquisition system, and a marine pressure sensor connected to both the standard constant temperature system and the standard constant pressure system.

[0007] A standard temperature control system is used to provide a controlled and monitorable temperature control environment for the calibrated marine pressure sensor;

[0008] A standard constant pressure system is used to provide a controllable standard pressure source for the marine pressure sensor;

[0009] The data acquisition system is used to simultaneously acquire temperature data output by the standard constant temperature system, standard pressure data output by the standard constant pressure system, and pressure sensing signals output by the marine pressure sensor.

[0010] The data processing unit, which is communicatively connected to the data acquisition system, is used to receive and process the acquired data. By establishing a mathematical relationship model between the output pressure value of the marine pressure sensor and the corresponding ambient temperature and standard pressure value, it generates correction parameters to compensate for pressure measurement errors caused by temperature changes.

[0011] The standard constant temperature system includes: a constant temperature chamber, a standard platinum resistance thermometer, a temperature measuring bridge, a standard resistor, and a constant temperature oil bath;

[0012] The constant temperature chamber is a closed temperature-controlled space used to house the marine pressure sensor, placing it in a uniform and settable temperature field.

[0013] The standard platinum resistance thermometer is fixedly installed inside the constant temperature chamber, and its temperature sensing end is in contact with the housing of the marine pressure sensor to accurately sense the actual temperature of the sensor body.

[0014] One side of the temperature measuring bridge is connected to a standard platinum resistance thermometer via a wire, and the other side is connected to a standard resistor, forming a complete temperature measurement comparison circuit.

[0015] The constant temperature oil bath is filled with a heat-conducting medium and completely submerges the standard resistor to maintain the standard resistor at a known temperature, thereby ensuring its resistance value remains constant.

[0016] The standard constant pressure system includes: a pressure generator, a set of weights, a standard pressure gauge, and pressure piping;

[0017] The weight set consists of multiple weights with different nominal masses, which are loaded onto the piston tray of the pressure generator and act directly on the piston area through gravity, thereby generating a standard pressure value in a closed pressure medium.

[0018] The pressure pipeline serves as a pressure transmission channel. One end is connected to the pressure output port of the pressure generator, and the other end branches off to connect to the pressure interface of the standard pressure gauge and the marine pressure sensor located in the constant temperature chamber, forming a parallel test loop with a common pressure source and dual indications.

[0019] The pressure generator includes: a pressure medium storage tank, a pressure medium storage tank switch, and a pressure regulator;

[0020] The pressure medium storage tank is a sealed tank used to store fluids that serve as pressure transmission media.

[0021] The pressure medium storage tank switch is installed between the outlet of the pressure medium storage tank and the pressure pipeline, and is used to cut off the direct connection between the tank and the test circuit after initial pressurization.

[0022] The pressure regulator is installed in series on the pressure pipeline and is located downstream of the pressure medium storage tank switch. It is used to fine-tune the pressure to ensure pressure stability.

[0023] The standard pressure gauge of the standard constant pressure system is installed inside the constant temperature chamber;

[0024] The pressure port of the marine pressure sensor is inserted into the wall of the constant temperature chamber through a pressure pipe and is connected in parallel with the pressure port of the standard pressure gauge placed inside the chamber, so that both are subjected to the same hydrostatic pressure introduced by the external pressure source.

[0025] The standard platinum resistance thermometer, marine pressure sensor, and standard pressure gauge are closely arranged within the same effective constant temperature area of ​​the constant temperature chamber to ensure that the ambient temperature remains highly consistent in both spatial distribution and temporal variation.

[0026] The data acquisition system includes: a temperature signal acquisition module, a sensor signal acquisition module, and a signal conditioning and storage module;

[0027] The temperature signal acquisition module uses a temperature measuring bridge as its front end, and its input end is connected to the analog voltage output end of the temperature measuring bridge. It is used to receive and digitize the primary voltage signal converted from the resistance value of a standard platinum resistance thermometer.

[0028] The sensor signal acquisition module is connected to the output terminal of the ocean pressure sensor and uses it to capture the original sensing electrical signal generated by the ocean pressure sensor when it is subjected to pressure in real time.

[0029] The signal conditioning and storage module is connected to the temperature signal acquisition module and the sensor signal acquisition module respectively to receive digital data streams; at the same time, it establishes a data link with the standard pressure gauge (7) through the communication interface to read the standard pressure value;

[0030] The signal conditioning and storage module is equipped with a synchronous clock and a buffer memory. It applies a unified timestamp to the temperature data, raw sensor signal data and standard pressure data from three independent sources, and performs alignment and temporary storage. Finally, it transmits a complete calibration data package containing standard temperature, sensor output and standard pressure to the data processing unit for subsequent modeling and analysis.

[0031] A calibration method for a temperature-compensated marine pressure sensor calibration device includes the following steps:

[0032] Step S1: Install the marine pressure sensor to be calibrated in the constant temperature chamber of the standard constant temperature system, so that its pressure sensing component is in the same constant temperature zone as the standard platinum resistance thermometer and the standard pressure gauge; start the standard constant temperature system, the standard constant pressure system and the data acquisition system;

[0033] Step S2: Set multiple target temperature values ​​through a standard constant temperature system to cover the expected operating temperature range of the marine pressure sensor, so that a uniform and stable temperature field is formed inside the constant temperature chamber, and perform subsequent pressure calibration steps at each temperature point;

[0034] Step S3: At each set temperature point, a series of standard pressure values ​​are generated by the pressure generator of the standard constant pressure system, wherein different combinations of mass are loaded by a set of weights to obtain a precise and graded pressure source;

[0035] Step S4: The generated standard pressure is simultaneously and equally transmitted through the pressure pipeline to the pressure interface of the standard pressure gauge and the marine pressure sensor located in the constant temperature chamber.

[0036] Step S5: After each temperature-pressure combination condition stabilizes, the precise ambient temperature data measured by the standard platinum resistance thermometer, the standard pressure data indicated by the standard pressure gauge, and the raw pressure sensing signal output by the marine pressure sensor are synchronously collected and recorded through the data acquisition system.

[0037] Step S6: The data processing unit processes the collected data and calculates the deviation between the output pressure value of the ocean pressure sensor and the standard pressure value at each temperature point; using the deviation data under all temperature-pressure combinations and the ambient temperature data, a mathematical relationship model describing the influence of temperature on the output pressure deviation of the ocean pressure sensor is established by fitting the data using the least squares method.

[0038] Step S7: Based on the mathematical relationship model established in Step S6, generate correction coefficients or compensation functions for temperature and pressure compensation of the marine pressure sensor in actual use.

[0039] In step S5, the synchronous acquisition of temperature data from a standard platinum resistance thermometer, standard pressure data from a standard pressure gauge, and pressure sensing signals output by a marine pressure sensor specifically includes:

[0040] After the temperature inside the constant temperature chamber stabilizes at the set value, the data acquisition system simultaneously starts acquiring three signals.

[0041] For temperature data: The temperature measuring bridge measures the resistance value of the standard platinum resistance thermometer, and combines it with the resistance value of the standard resistor placed in the constant temperature oil bath at a known temperature to obtain the resistance ratio. Then, according to the calibration table of the standard platinum resistance thermometer under the ITS-90 international temperature scale, the standard temperature value t of the current environment is calculated and recorded by the temperature signal acquisition module of the data acquisition system.

[0042] For standard pressure data: The pressure value indicated by the standard pressure gauge is directly read from the data link and used as the standard pressure value under the current operating conditions;

[0043] For the sensor pressure sensing signal: the original electrical signal output by the marine pressure sensor when it is subjected to pressure is collected in real time, and the corresponding sensor pressure value is calculated through its known pressure-to-electrical signal conversion coefficient.

[0044] The above three data sources are aligned and bound using a unified timestamp to ensure that the temperature value t, standard pressure value, and sensor pressure value in each data packet are strictly synchronized in time.

[0045] In step S6, establishing a mathematical relationship model between the output pressure value of the ocean pressure sensor and the corresponding ambient temperature and standard pressure value specifically involves:

[0046] The established temperature compensation mathematical model is based on the functional relationship between standard temperature and pressure deviation. The pressure correction coefficient is obtained by fitting using the least squares method, and its mathematical relationship is expressed as follows:

[0047]

[0048] Where A, B, and C are pressure correction factors. The difference between the standard pressure and the pressure from the marine pressure sensor. Standard temperature;

[0049] The pressure correction coefficient obtained through the temperature compensation function is used to correct the measurement results of the marine pressure sensor under different temperature conditions, so as to eliminate the influence of temperature changes on the accuracy of pressure measurement.

[0050] It also includes: pre-setting a sequence of temperature calibration points covering the expected operating temperature range of the marine pressure sensor before performing the multi-point temperature calibration;

[0051] The temperature range is -1℃ to 35℃;

[0052] For each set temperature calibration point, perform the following sub-steps:

[0053] a. Set the target temperature of the constant temperature chamber to the current temperature calibration point value, and start the temperature control to make the temperature inside the chamber reach the set value and remain stable;

[0054] b. After the temperature stabilizes, a set of standard pressure calibration points covering the range of the marine pressure sensor are set sequentially; for each pressure calibration point, the standard constant pressure system generates and maintains the corresponding standard pressure by combining the mass of the weight set and adjusting the pressure regulator.

[0055] c. After the operating conditions stabilize at each temperature-pressure calibration point, perform a synchronous data acquisition operation to obtain a set of raw calibration data;

[0056] d. After completing the data collection for all preset temperature calibration points and corresponding pressure calibration points, summarize all the original calibration data.

[0057] The present invention has the following beneficial effects and advantages:

[0058] 1. The core of this invention is to ensure the measurement accuracy of marine pressure sensors in environments with wide temperature gradients in the ocean by eliminating the influence of temperature drift on pressure measurements. This method establishes a mathematical compensation model for temperature and pressure through multi-point temperature and pressure calibration, which can improve the pressure measurement accuracy of marine pressure sensors to ±0.1%FS, meeting the high-precision measurement requirements of fields such as marine hydrological observation and deep-sea exploration.

[0059] 2. In view of the fact that most existing calibrations are only performed at a single temperature (such as room temperature), which cannot reflect the wide temperature range of the actual ocean from above 35°C at the surface to 0°C or even -3°C in the deep sea, this method establishes an accurate temperature-pressure mathematical compensation model by implementing multi-temperature gradient pressure calibration, which effectively breaks through the temperature range limitation of conventional verification procedures and enables the sensor to maintain stable accuracy in complex temperature environments throughout the ocean.

[0060] 3. This invention uses the least squares method to fit and correct the calibration data, establishing a system as follows: The pressure correction coefficient is accurately calculated using compensation functions of the same form. These coefficients can systematically eliminate measurement errors caused by temperature changes, and the compensation effect can be directly used to correct the sensor output in real time and accurately.

[0061] 4. This invention is a key supplement and optimization for metrology work in special application scenarios with wide temperature gradients in the ocean. It promotes the development of ocean pressure sensor metrology towards precision and standardization. By introducing an improved high-precision standard constant pressure system and a standard constant temperature system, and combining them with standardized calibration procedures, it provides reliable and traceable metrological support for observation data in fields such as oceanographic observation and deep-sea exploration.

[0062] 5. The calibrated marine pressure sensor of this invention, with its high precision characteristics due to wide temperature range compensation, can be directly and reliably applied to actual marine hydrological observation, deep-sea exploration, and other observation activities. This ensures that the pressure data acquired under real ocean wide temperature gradient environments has high reliability and consistency, providing a solid guarantee for related scientific research and engineering applications. Attached Figure Description

[0063] Figure 1 This is a flowchart of the calibration process method of the present invention;

[0064] Figure 2 This is a schematic diagram of the calibration system of the present invention;

[0065] Among them, 1 is a standard resistor, 2 is a constant temperature oil bath, 3 is a temperature measuring bridge, 4 is a standard platinum resistance thermometer, 5 is a marine pressure sensor, 6 is a constant temperature chamber, 7 is a standard pressure gauge, 8 is a pressure pipeline, 9 is a pressure medium storage tank, 10 is a pressure medium storage tank switch, 11 is a pressure regulator, 12 is a weight set, 13 is a data acquisition system, 100 is a standard constant temperature system, and 200 is a standard constant pressure system. Detailed Implementation

[0066] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0067] I. Device Structure and Implementation Method

[0068] like Figure 2 As shown, the temperature-compensated marine pressure sensor calibration device of the present invention mainly includes the following parts:

[0069] (1) Standard constant temperature system 100

[0070] The system includes a constant temperature chamber 6, a standard platinum resistance thermometer 4, a temperature measuring bridge 3, a standard resistor 1, and a constant temperature oil bath 2.

[0071] The constant temperature chamber 6 is a sealed temperature control chamber with a uniform temperature field inside, used to house the ocean pressure sensor 5.

[0072] A standard platinum resistance thermometer 4 is fixed inside the box, with its sensing end in close contact with the housing of the sensor 5 to sense the actual temperature of the sensor.

[0073] The temperature measuring bridge 3 is connected to the standard platinum resistance thermometer 4 and the standard resistor 1 through wires to form a temperature measurement comparison circuit.

[0074] The standard resistor 1 is completely immersed in the heat-conducting medium of the constant temperature oil bath 2 to ensure that its resistance value remains constant.

[0075] (2) Standard constant pressure system 200

[0076] The system includes a pressure generator, a weight set 12, a standard pressure gauge 7, and a pressure pipeline 8.

[0077] The pressure generator consists of a pressure medium storage tank 9, a switch 10, and a pressure regulator 11, and is used to generate and regulate pressure.

[0078] The weight set 12 generates a precise standard pressure by combining different masses and applying them to the piston of the pressure generator. The weight set 12 can be combined to produce different masses, which, together with the pressure generator 11, can provide different pressures. The pressure generator 11 and the weight set 12 work together to generate a pressure source, and the pressure is adjusted to stabilize it.

[0079] Pressure pipe 8 simultaneously transmits pressure to standard pressure gauge 7 and marine pressure sensor 5 inside constant temperature chamber 6.

[0080] The standard pressure gauge 7 is connected in parallel with the pressure port of sensor 5 to ensure that both are subjected to the same static pressure.

[0081] (3) Data acquisition system 13

[0082] The system includes a temperature signal acquisition module, a sensor signal acquisition module, and a signal conditioning and storage module.

[0083] The temperature signal acquisition module uses the temperature measuring bridge 3 as the front end. Its input end is connected to the analog voltage output end of the temperature measuring bridge 3 to receive and digitize the primary voltage signal converted from the resistance value of the standard platinum resistance thermometer 4.

[0084] The sensor signal acquisition module is connected to the output terminal of the ocean pressure sensor 5 to capture the raw sensing electrical signal generated by the ocean pressure sensor 5 when it is subjected to pressure in real time.

[0085] The signal conditioning and storage module is connected to the temperature signal acquisition module and the sensor signal acquisition module respectively to receive digital data streams; at the same time, it establishes a data link with the standard pressure gauge 7 through the communication interface to read the standard pressure value.

[0086] The signal conditioning and storage module is equipped with a synchronous clock and a buffer memory. It applies a unified timestamp to the temperature data, raw sensor signal data and standard pressure data from three independent sources, and performs alignment and temporary storage. Finally, it transmits a complete calibration data package containing standard temperature, sensor output and standard pressure to the data processing unit for subsequent modeling and analysis.

[0087] (4) Overall layout and connection

[0088] The standard platinum resistance thermometer 4, the marine pressure sensor 5, and the standard pressure gauge 7 are all arranged in the same constant temperature zone of the constant temperature chamber 6 to ensure temperature consistency. The pressure pipe 8 passes through the chamber wall to connect the external pressure source to the components inside the chamber.

[0089] II. Implementation Methods of Calibration

[0090] like Figure 1 As shown, the calibration method of the present invention is performed according to the following steps:

[0091] Step S1: Preparatory work

[0092] The preparatory work involves connecting the calibrated marine pressure sensor to the standard constant pressure system, placing it in the standard constant temperature system and turning it on, setting the required calibration temperature point, and waiting for the standard constant temperature system to stabilize before starting the calibration. The specific operation is as follows:

[0093] Install the marine pressure sensor 5 to be calibrated in the constant temperature chamber 6, ensuring that it is in the same temperature range as the standard platinum resistance thermometer 4 and the standard pressure gauge 7. Start the standard constant temperature system 100, the standard constant pressure system 200, and the data acquisition system 13.

[0094] Step S2: Set the temperature sequence

[0095] Multiple temperature calibration points were set to cover the sensor's expected operating temperature range (-1℃ to 35℃). Subsequent pressure calibration was performed at each temperature point after the temperature inside the constant temperature chamber 6 had stabilized.

[0096] Step S3: Apply standard pressure sequence

[0097] At each temperature point, different masses are combined using the weight set 12, and the pressure regulator 11 is used for fine-tuning to generate a series of standard pressure values ​​covering the sensor's range.

[0098] Step S4: Pressure Transmission

[0099] The standard pressure is simultaneously and equally transmitted to the standard pressure gauge 7 and the marine pressure sensor 5 via the pressure pipeline 8.

[0100] Step S5: Synchronous Data Acquisition

[0101] The three data streams are aligned using a unified timestamp to ensure strict synchronization.

[0102] The temperature data from the standard platinum resistance thermometer 4, the standard pressure data from the standard pressure gauge 7, and the pressure sensing signal output from the marine pressure sensor 5 are collected simultaneously, specifically as follows:

[0103] After the temperature in the constant temperature chamber 6 stabilizes at the set value, the data acquisition system 13 simultaneously starts acquiring three signals.

[0104] After the temperature-pressure conditions stabilize, the data acquisition system 13 will simultaneously acquire the following three data streams:

[0105] For temperature data: The temperature measuring bridge 3 measures the resistance value of the standard platinum resistance thermometer 4, and combines it with the resistance value of the standard resistor 1 placed in the constant temperature oil bath 2 at a known temperature to obtain the resistance ratio. Then, according to the calibration table of the standard platinum resistance thermometer 4 under the ITS-90 international temperature scale, the standard temperature value t of the current environment is calculated and recorded by the temperature signal acquisition module of the data acquisition system 13.

[0106] For standard pressure data: The pressure value indicated by the standard pressure gauge 7 is directly read from the data link and used as the standard pressure value under the current operating conditions;

[0107] For the sensor pressure sensing signal: the original electrical signal output by the marine pressure sensor 5 when it is subjected to pressure is collected in real time, and the corresponding sensor pressure value is calculated through its known pressure-to-electrical signal conversion coefficient.

[0108] The above three data sources are aligned and bound using a unified timestamp to ensure that the temperature value t, standard pressure value, and sensor pressure value in each data packet are strictly synchronized in time.

[0109] Step S6: Data Processing and Modeling

[0110] Data processing mainly includes: standard temperature processing and pressure processing of the marine pressure sensor 5. The standard temperature is calculated using the standard resistor 1 and calibration parameters. The pressure of the marine pressure sensor 5 is calculated using its own pressure coefficient.

[0111] The data processing unit calculates the deviation Δp between the sensor output and the standard pressure for each temperature-pressure combination, and establishes a temperature compensation model using the least squares method by fitting all the data.

[0112]

[0113] Where A, B, and C are pressure correction factors. The difference between the standard pressure and the pressure from the marine pressure sensor. This is the standard temperature; it should be noted that the standard temperature is the temperature under the ITS-90 temperature scale.

[0114] Step S7: Generate compensation parameters

[0115] Based on the above model, compensation coefficients or compensation functions are generated for real-time temperature-pressure compensation of marine pressure sensors in actual use.

[0116] III. Implementation Examples:

[0117] like Figure 1 and Figure 2 The diagram shows a calibration process and a calibration system diagram for a temperature-compensated marine pressure sensor. The calibration process mainly includes preparatory work, a standard constant temperature system, a standard constant pressure system, a data acquisition system, data processing, and a mathematical compensation model.

[0118] Preparations: Start the constant temperature chamber 6 and the standard constant temperature oil bath 2.

[0119] Connect the standard platinum resistance thermometer 4 (SPRT) to the standard resistor 1 and the temperature measuring bridge 3, start the temperature measuring bridge 3, start the standard pressure gauge 7, connect the marine pressure sensor 5 and the standard pressure gauge 7 to the standard constant pressure system 200, and start the computer to open the data acquisition system 13.

[0120] The standard constant temperature system 100 and the constant temperature chamber 6 are set to the required calibration temperature. After each temperature point is calibrated, the next temperature point is set until the calibration is completed. The temperature of the standard constant temperature oil bath 2 is set to be consistent with the temperature during the calibration of the standard resistor 1. The standard platinum resistance thermometer 4 is connected to the temperature measuring bridge 3, and the temperature measuring bridge 3 is connected to the standard resistor 1. The temperature measuring bridge 3 is started to test whether the standard platinum resistance thermometer 4 is communicating. If the communication is successful, wait for data acquisition.

[0121] The standard constant pressure system 200 connects the marine pressure sensor 5 and the standard pressure gauge 7. When the marine pressure sensor 5 and the standard pressure gauge 7 are activated, the weight group 12 is assembled to form a certain mass to obtain the pressure that needs to be calibrated.

[0122] After the temperature and pressure stabilize, the data acquisition system 13 begins to acquire data. The standard platinum resistance thermometer 4 and the marine pressure sensor 5 are automatically acquired by the data acquisition system 13, and the standard pressure is directly read through the standard pressure gauge 7.

[0123] Data processing involves obtaining the actual temperature using the temperature-resistance calculation formula of a standard platinum resistance thermometer 4, and obtaining the test pressure from the raw electrical signal of the marine pressure sensor 5 via software.

[0124] The mathematical compensation model is obtained by least squares fitting of the pressure difference between the standard temperature and the pressure of the ocean pressure sensor 5 and the standard pressure to obtain the pressure correction coefficient.

[0125] Standard resistor 1 serves as the reference resistor for standard platinum resistance thermometer 4. Its purpose is to obtain the resistance value of standard platinum resistance thermometer 4 via temperature measuring bridge 3, thereby obtaining the true temperature value of the constant temperature chamber 6. Standard resistor 1 is connected to temperature measuring bridge 3, and standard platinum resistance thermometer 4 is also connected to temperature measuring bridge 3. Through the connection established between temperature measuring bridge 3, standard resistor 1, and standard platinum resistance thermometer 4, the resistance value of standard platinum resistance thermometer 4 is obtained. The constant temperature oil bath 2 provides a constant temperature environment for standard resistor 1, ensuring the accuracy of its resistance value. The marine pressure sensor 5 and standard pressure gauge 7 are connected together to the standard constant pressure system 200 via pressure pipe 8. The quasi-constant pressure system 200 consists of a standard pressure gauge 7, pressure pipeline 8, pressure medium storage tank 9, pressure medium storage tank switch 10, pressure regulator 11, and weight set 12; the constant temperature chamber 6 provides a consistent constant temperature environment for the marine pressure sensor 5 and the standard pressure gauge 7; the pressure medium storage tank switch 10 ensures the sealing of the constant pressure system after being closed, providing a closed constant pressure environment; the pressure regulator 11 finely adjusts the constant pressure environment to maintain it within a certain accuracy range; the weight set 12 can combine different masses to generate the required pressure; the data acquisition system 13 acquires the output values ​​of the standard platinum resistance thermometer 4 and the marine pressure sensor 5.

[0126] In summary, in conjunction with the embodiments of the present invention, the present invention establishes an accurate temperature-pressure mathematical model through synchronous calibration across the entire temperature range at multiple temperature and pressure points, achieving high-precision temperature compensation. It is particularly suitable for ocean environments with wide temperature gradients, improving the measurement reliability of ocean pressure sensors and providing reliable metrological support for fields such as ocean observation and deep-sea exploration.

[0127] Those skilled in the art will understand that the above description is merely a preferred embodiment of the present invention, and the features described in the various embodiments and / or claims of this disclosure can be combined or combined in various ways, even if such combinations or combinations are not explicitly described in this disclosure. This is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0128] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention. Clearly, those skilled in the art can make various alterations and modifications to the invention without departing from its spirit and scope. Thus, if these modifications and modifications of the invention fall within the scope of the claims and their equivalents, the invention is also intended to include these modifications and modifications.

Claims

1. A temperature-compensated marine pressure sensor calibration device, characterized by, The application relates to a marine pressure sensor calibration system, which comprises a standard constant temperature system (100), a standard constant pressure system (200), a data acquisition system (13) and a marine pressure sensor (5) connected with the standard constant temperature system (100) and the standard constant pressure system (200) simultaneously. The standard constant temperature system (100) is used for providing a controllable and monitorable constant temperature environment for the calibrated marine pressure sensor (5). The standard constant pressure system (200) is used for providing a controllable standard pressure source for the marine pressure sensor (5). The data acquisition system (13) is used for synchronously acquiring temperature data output by the standard constant temperature system (100), standard pressure data output by the standard constant pressure system (200) and pressure sensing signals output by the marine pressure sensor (5). A data processing unit is in communication connection with the data acquisition system (13) and is used for receiving and processing the acquired data, generating correction parameters for compensating pressure measurement errors caused by temperature changes by establishing a mathematical relation model between output pressure values of the marine pressure sensor (5) and corresponding environment temperature and standard pressure values. The standard constant temperature system (100) comprises a thermostat (6), a standard platinum resistance thermometer (4), a temperature measuring bridge (3), a standard resistance (1) and a constant temperature oil tank (2).

2. A temperature-compensated marine pressure sensor calibration device according to claim 1, wherein, The thermostat (6) is a closed temperature control space used for arranging the marine pressure sensor (5) to be in a uniform and settable temperature field. The standard platinum resistance thermometer (4) is fixedly installed in the thermostat (6) and has a temperature sensing end in contact with a shell of the marine pressure sensor (5) to accurately sense an actual temperature of the sensor body. One side measuring port of the temperature measuring bridge (3) is connected with the standard platinum resistance thermometer (4) through wires, and the other side reference port is connected with the standard resistance (1), so that a complete temperature measuring comparison circuit is formed. The constant temperature oil tank (2) is filled with a heat conducting medium and completely immerses the standard resistance (1), so that the standard resistance (1) is maintained at a known temperature, thereby ensuring that the resistance value of the standard resistance (1) is constant. The standard constant pressure system (200) comprises a pressure generator, a weight group (12), a standard pressure gauge (7) and a pressure pipeline (8).

3. A temperature-compensated marine pressure sensor calibration device according to claim 1, wherein, The weight group (12) is composed of multiple weights with different nominal masses and is loaded on a piston tray of the pressure generator, so that the standard pressure value is generated in a closed pressure medium through the gravity directly acting on the piston area. The pressure pipeline (8) is used as a pressure transmission channel, one end of which is connected with a pressure output port of the pressure generator, and the other end is branched and connected with the standard pressure gauge (7) and a pressure receiving interface of the marine pressure sensor (5) in the thermostat (6) respectively, so that a common pressure source, double-indication parallel test circuit is formed. The pressure generator comprises a pressure medium storage tank (9), a pressure medium storage tank switch (10) and a pressure regulator (11).

4. A temperature-compensated marine pressure sensor calibration device according to claim 3, wherein, The pressure medium storage tank (9) is a sealed tank body used for storing fluid as a pressure transmission medium. ​ The pressure medium storage tank switch (10) is installed between the outlet of the pressure medium storage tank (9) and the pressure pipeline (8) for cutting off the direct communication between the tank body and the test loop after initial pressurization; The pressure regulator (11) is installed in series on the pressure pipeline (8) and downstream of the pressure medium storage tank switch (10) for fine adjustment of the pressure to ensure the stability of the pressure.

5. A temperature-compensated marine pressure sensor calibration device according to claim 2 or 3, characterised in that, The standard pressure gauge (7) of the standard constant pressure system (200) is arranged in the thermostat (6); The pressure receiving port of the marine pressure sensor (5) penetrates the wall of the thermostat (6) through the pressure pipeline (8) and is connected in parallel with the pressure receiving port of the standard pressure gauge (7) arranged in the thermostat, so that both of them bear the same hydrostatic pressure introduced by the external pressure source; The standard platinum resistance thermometer (4), the marine pressure sensor (5) and the standard pressure gauge (7) are closely arranged in the same effective constant temperature area of the thermostat (6) to ensure that the ambient temperature is highly consistent in spatial distribution and time variation.

6. The temperature-compensated marine pressure sensor calibration device of claim 1, wherein, The data acquisition system (13) comprises a temperature signal acquisition module, a sensor signal acquisition module and a signal conditioning and storage module; The temperature signal acquisition module takes the temperature measurement bridge (3) as the front end, the input end of which is connected with the analog voltage output end of the temperature measurement bridge (3) for receiving and digitizing the primary voltage signal converted from the resistance value of the standard platinum resistance thermometer (4); The sensor signal acquisition module is connected with the output end of the marine pressure sensor (5) for capturing the original sensor electric signal generated by the marine pressure sensor (5) when bearing pressure in real time; The signal conditioning and storage module is connected with the temperature signal acquisition module and the sensor signal acquisition module respectively for receiving the digitized data stream; at the same time, a data link is established with the standard pressure gauge (7) through a communication interface for reading the standard pressure value; The signal conditioning and storage module is internally provided with a synchronous clock and a buffer memory, which applies a unified time stamp to the temperature data, the sensor original signal data and the standard pressure data from three independent sources, aligns and temporarily stores them, and finally transmits a complete calibration data package containing the standard temperature, the sensor output and the standard pressure to the data processing unit for subsequent modeling analysis.

7. The method of calibrating a temperature-compensated marine pressure sensor calibration device of claim 1, wherein, The method comprises the following steps: Step S1: installing the marine pressure sensor (5) to be calibrated in the thermostat (6) of the standard constant temperature system (100) so that the pressure sensing part is in the same constant temperature area as the standard platinum resistance thermometer (4) and the standard pressure gauge (7); starting the standard constant temperature system (100), the standard constant pressure system (200) and the data acquisition system (13); Step S2: setting a plurality of target temperature values through the standard constant temperature system (100) to cover the temperature range in which the marine pressure sensor is expected to work, so that a uniform and stable temperature field is formed in the thermostat (6), and the subsequent pressure calibration steps are performed at each temperature point; Step S3: At each set temperature point, a series of standard pressure values are generated by the pressure generator of the standard constant pressure system (200) with different combined masses loaded by the weight set (12) to obtain accurate and graded pressure sources; Step S4: The generated standard pressure is simultaneously and equally transmitted to the standard pressure gauge (7) and the pressure receiving interface of the marine pressure sensor (5) located in the thermostat (6) through the pressure pipeline (8); Step S5: After each temperature-pressure combination condition is stable, the accurate environmental temperature data measured by the standard platinum resistance thermometer (4), the standard pressure data indicated by the standard pressure gauge (7), and the original pressure sensing signal output by the marine pressure sensor (5) are synchronously collected and recorded by the data acquisition system (13); Step S6: The data processing unit processes the collected data, calculates the deviation between the output pressure value of the marine pressure sensor (5) and the standard pressure value at each temperature point, and establishes a mathematical relationship model describing the influence of temperature on the output pressure deviation of the marine pressure sensor by least square fitting using the deviation data and environmental temperature data under all temperature-pressure combinations; Step S7: Based on the mathematical relationship model established in step S6, a correction coefficient or compensation function for temperature and pressure compensation of the marine pressure sensor in actual use is generated.

8. The method of calibrating a temperature-compensated marine pressure sensor calibration device of claim 7, wherein, In step S5, the temperature data of the standard platinum resistance thermometer (4), the standard pressure data of the standard pressure gauge (7), and the pressure sensing signal output by the marine pressure sensor (5) are synchronously collected, specifically: After the temperature in the thermostat (6) stabilizes at the set value, the data acquisition system (13) simultaneously starts collecting the three signals; For temperature data: the temperature measuring bridge (3) measures the resistance value of the standard platinum resistance thermometer (4), combines the resistance value of the standard resistance (1) placed in the thermostat oil tank (2) at a known temperature, obtains the resistance ratio, and then calculates the standard temperature value t of the current environment according to the scale table of the standard platinum resistance thermometer (4) under the ITS-90 international temperature scale, and records it by the temperature signal acquisition module of the data acquisition system (13); For standard pressure data: the pressure value indicated by the standard pressure gauge (7) is directly read through the data link, which is taken as the standard pressure value under the current condition; For sensor pressure sensing signal: the original electric signal output by the marine pressure sensor (5) when subjected to pressure is collected in real time, and the corresponding sensor pressure value is calculated through the known pressure-electric signal conversion coefficient; The collection of the above three data is aligned and bound by a unified timestamp, ensuring that the temperature value t, standard pressure value, and sensor pressure value in each data packet are strictly synchronized in time.

9. The method of calibrating a temperature-compensated marine pressure sensor calibration device of claim 7, wherein, In step S6, the mathematical relationship model between the output pressure value of the marine pressure sensor (5) and the corresponding environmental temperature and standard pressure value is established, specifically: The temperature compensation mathematical model is based on the functional relationship between the standard temperature and pressure deviation, and the pressure correction coefficient is obtained by least square fitting, and the mathematical relationship is represented as: ； Wherein, A, B, C are pressure correction coefficients, is the difference between the standard pressure and the pressure of the marine pressure sensor, is the standard temperature; The pressure correction coefficient obtained by the temperature compensation function is used to correct the measurement results of the marine pressure sensor under different temperature conditions, so as to eliminate the influence of temperature change on the pressure measurement accuracy.

10. The method of calibrating a temperature-compensated marine pressure sensor calibration device of claim 7, wherein, Further comprising: Before performing the multi-point temperature calibration, a set of temperature calibration points covering the expected working temperature range of the marine pressure sensor is preset; The temperature range is -1℃ to 35℃; For each preset temperature calibration point, the following sub-steps are performed: a. Set the target temperature of the thermostat (6) to the current temperature calibration point value, and start the temperature control to make the temperature in the box reach the set value and keep stable; b. After the temperature is stable, a set of standard pressure calibration points covering the range of the marine pressure sensor are set in turn; for each pressure calibration point, the standard constant pressure system (200) generates and maintains the corresponding standard pressure by combining the mass of the weight set (12) and adjusting the pressure regulator (11); c. After each temperature-pressure calibration point working condition is stable, a synchronous data acquisition operation is performed to obtain a set of calibration raw data; d. After the data acquisition of all preset temperature calibration points and corresponding pressure calibration points is completed, all calibration raw data are summarized.

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