Power system temperature in-situ calibration device and method based on flexible temperature sensor

Abstract

The present invention discloses an in-situ calibration device and method for power system temperature based on a flexible temperature sensor. The in-situ calibration device of the present invention has a built-in vibration sensor and a standard temperature sensor. When starting calibration, the built-in vibration sensor and the standard temperature sensor are taken out and fixed on the surface of the engine of the equipment power system, and connected to the electrical interface of the in-situ calibration device together with the temperature sensor to be calibrated. The temperature value of the flexible temperature sensor to be calibrated, the temperature value of the standard temperature sensor and the vibration parameters collected are input into the industrial control computer through the data acquisition device in the in-situ calibration device, and the calibration is completed through the temperature compensation formula obtained in the laboratory. The present invention improves the portability of the device, the calibration efficiency and flexibility during temperature calibration, and also improves the reliability and accuracy of the temperature sensor calibration results.

Description

Technical Field

[0001] The present invention belongs to the technical field of sensor in-situ calibration and temperature compensation, and in particular relates to a power system temperature in-situ calibration device and method based on a flexible temperature sensor. Background Art

[0002] The power system of the equipment has certain requirements for various working conditions (such as diesel engine lubricating oil temperature, cooling water temperature, etc.). At the same time, in order to ensure safe operation and normal work, it is necessary to monitor its working status (such as diesel engine lubricating oil temperature, cylinder explosion pressure, etc.), and a large number of sensors are installed for this purpose. Whether these sensors work properly directly affects the safety of the power system and even the entire weapon equipment.

[0003] Flexible temperature sensors have the advantages of short thermal dynamic response time, accurate temperature measurement position, easy integration, small installation space requirement, strong adhesion, etc. The thin film material can be directly arranged on the surface of the hot end component for real-time temperature measurement. It has good application prospects in temperature detection of equipment power systems.

[0004] The accuracy of temperature measurement is the premise for accurate monitoring and control of the power system status. The flexible temperature sensor is easily damaged and aged under high temperature, high noise, high vibration and other strong interference conditions in the power system, resulting in inaccurate temperature measurement. Therefore, it is necessary to periodically calibrate the flexible temperature sensor in the equipment power system to ensure the accuracy of the temperature measurement.

[0005] The traditional offline detection method is to remove the sensor from the instrument and send it to a laboratory or a calibration agency for offline testing using specialized instruments to determine whether its functions are normal and the parameters are correct. However, the instrument that has passed the standard laboratory environment may deviate from the indicated data when it is brought to the actual site of use. Summary of the invention

[0006] In view of the above-mentioned deficiencies of off-line temperature calibration, the present invention provides a power system temperature in-situ calibration device and method based on a flexible temperature sensor.

[0007] In order to solve the above problems, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a method for in-situ calibration of power system temperature based on a flexible temperature sensor, comprising:

[0009] Collecting vibration parameters, a temperature value of a first standard temperature sensor, and a temperature value of a first flexible temperature sensor to be calibrated;

[0010] According to the vibration parameters and temperature compensation fitting algorithm, the temperature deviation value caused by vibration is obtained;

[0011] Combining the temperature value of the first temperature sensor to be calibrated and the temperature deviation value to obtain a temperature correction value of the first flexible temperature sensor to be calibrated;

[0012] The temperature correction value of the first flexible temperature sensor to be calibrated is compared with the temperature value of the first standard temperature sensor to obtain a final indication error, thereby completing the calibration.

[0013] In a second aspect, the present invention provides a power system temperature in-situ calibration system based on a flexible temperature sensor, comprising:

[0014] A data acquisition unit, used for acquiring vibration parameters, a temperature value of a first standard temperature sensor, and a temperature value of a first flexible temperature sensor to be calibrated;

[0015] A temperature deviation value acquisition unit, used to acquire a temperature deviation value caused by vibration according to vibration parameters and a temperature compensation fitting algorithm;

[0016] a temperature correction value acquisition unit, configured to combine the temperature value of the first temperature sensor to be calibrated and the temperature deviation value to obtain a temperature correction value of the first flexible temperature sensor to be calibrated;

[0017] The result output unit is used to compare the temperature correction value of the first flexible temperature sensor to be calibrated with the temperature value of the first standard temperature sensor to obtain the final indication error and complete the calibration.

[0018] In a third aspect, the present invention provides a power system temperature in-situ device based on a flexible temperature sensor, which is integrated in a suitcase and includes an industrial control computer equipped with the power system temperature in-situ calibration system, a data acquisition device, a vibration sensor and a first standard temperature sensor.

[0019] In a fourth aspect, the present invention provides a computer device, comprising a memory, a processor, and computer executable instructions stored in the memory and executable on the processor, wherein the processor implements the power system temperature in-situ calibration method when executing the instructions.

[0020] In a fifth aspect, the present invention provides a computer storage medium, wherein the computer storage medium stores computer executable instructions, and the computer executable instructions, when executed, implement the power system temperature in-situ calibration method.

[0021] Since the engine of the power system will generate high vibration when it is working, the in-situ calibration method adopted by the present invention installs a vibration sensor on the surface of the engine and connects it to the in-situ calibration device. By measuring its vibration frequency and amplitude, the final calibration temperature is obtained according to the temperature compensation algorithm obtained in the laboratory.

[0022] The method for temperature compensation of the flexible temperature sensor described in the present invention uses a small exciter to provide a stable frequency and amplitude in a laboratory environment to simulate the vibration of the engine of the equipment power system when it is working. According to the voltage values ​​output by the standard temperature sensor at different frequencies and amplitudes, a temperature compensation model is established for use in the in-situ calibration device.

[0023] The method for predicting the internal temperature of an engine of an equipment power system described in the present invention is used to solve the technical problem of difficulty in predicting the internal temperature of an engine of an equipment power system, and can predict the internal output temperature thereof through a temperature dynamic prediction model based on relevant input data collected in the test. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic diagram of the appearance of a device according to an embodiment of the present application;

[0025] Figure 2 is a schematic diagram of the overall structure of the device of an embodiment of the present application;

[0026] Figure 3 is a schematic top view of a device according to an embodiment of the present application;

[0027] Figure 4 Schematic diagram of an experimental platform for a calibration method according to an embodiment of the present application;

[0028] Figure 5 is a schematic diagram of the installation of the vibration sensor and the flexible temperature sensor of the embodiment of the present application;

[0029] Figure 6 It is a calibration flow chart of an embodiment of the present application. DETAILED DESCRIPTION

[0030] like Figure 1 The figure is a schematic diagram of the appearance of the in-situ calibration device of an embodiment of the present application. The whole set of in-situ calibration device is integrated into a trolley case, and two universal wheels are installed at the bottom of the trolley case to facilitate the staff to carry it.

[0031] like Figure 2 , which is a schematic diagram of the overall structure of the in-situ calibration device of the above embodiment after being opened, the in-situ calibration device includes a box 101, an industrial control computer 102, a power interface 103, a UART interface 104, a One-Wire interface 105, an RS232 interface 106, an RS485 interface 107, three groups of USB interfaces 108, a data logger 109, a heat dissipation cover 110, a power switch 111, a start / stop button 112, a vibration sensor 113 and a standard temperature sensor 114.

[0032] The in-situ calibration device in the present application is designed to be integrated and miniaturized. The integrated and miniaturized design means that the industrial control computer 102, the standard temperature sensor 114, the data acquisition device 109, etc. are integrated in the box 101, so that when the calibration staff conducts on-site calibration work, there is no need to send the disassembled flexible temperature sensor to the laboratory for calibration, but the calibration work can be carried out on-site through the in-situ calibration device they carry.

[0033] The in-situ calibration device in this application is multi-interface and multi-functional. The multi-interface means that the in-situ calibration device is equipped with a variety of different flexible temperature sensor interfaces to be calibrated, including UART interface 104, One-Wire interface 105, RS-232 interface 106, RS-485 interface 107, and USB interface 108, which expands the application scope of the device. Among them, there are one group of UART interface, RS485 interface, RS232 interface, and One-Wire interface, and three groups of USB interface. It can adapt to a variety of different types of temperature sensors, which improves the calibration efficiency and flexibility; the multi-functionality means that in addition to calibrating the flexible temperature sensor, the in-situ calibration device can also predict the internal temperature of the engine of the equipment power system on site through the internal temperature dynamic prediction model. The temperature dynamic prediction model, that is, in this application, inputs the temperature correction value of the flexible temperature sensor to be calibrated into the temperature dynamic prediction fitting formula to output the internal temperature data of the engine of the equipment power system at the current moment. The temperature dynamic fitting formula can use the temperature data of at least two temperature sampling points on the surface of the engine of the equipment power system as input, combined with the temperature dynamic prediction fitting parameters, to accurately output the internal temperature of the engine of the equipment power system.

[0034] like Figure 3 As shown, Figure 2The top view of the in-situ calibration device is shown, and the in-situ calibration device charges the entire device through the power interface 103; the calibration staff turns on the in-situ calibration device by rotating the power switch 111, and the device is pre-started at this time; then press the start switch 112 of the industrial control computer 102, and press it again to turn off the industrial control computer 102. When the staff performs calibration work on site, they take out the vibration sensor 113 in the in-situ calibration device, stick it on the surface of the equipment power system engine, and connect the other end to the USB interface 108 of the device; take out the standard temperature sensor 114 (i.e., the first standard temperature sensor) in the in-situ calibration device, stick it on the surface of the equipment power system engine, and connect the other end to another USB interface 108 of the device. The flexible temperature sensor to be calibrated (i.e., the first flexible temperature sensor to be calibrated) installed on the surface of the equipment power system engine is also connected to a USB interface 108, and the temperature value and vibration parameters are obtained through the data collector 109; if the electrical interface of the flexible temperature sensor on site is not a USB interface, it can be connected to multiple different electrical interfaces next to the industrial control computer 102. After obtaining the temperature value and vibration parameters, the indication error of the flexible temperature sensor to be calibrated can be obtained according to the temperature compensation formula described below, and then temperature calibration can be performed on it.

[0035] The in-situ calibration method in the present application is simplified. Compared with the traditional cumbersome temperature calibration method, the temperature calibration method adopted in the present application does not require the removal of the flexible temperature sensor installed on the surface of the equipment power system. It only needs to connect the flexible temperature sensor to be calibrated to the in-situ calibration device, and the standard temperature sensor is also connected to the in-situ calibration device. The data collector inside the device will collect vibration parameters (vibration frequency T and amplitude A), the temperature value of the standard temperature sensor, and the temperature value of the flexible temperature sensor to be calibrated. Since vibration will cause changes in the resistance value of the flexible temperature sensor, according to the vibration parameters, the device of the present application uses an internal temperature compensation fitting algorithm to fit a temperature deviation value caused by vibration. The temperature value of the temperature sensor to be calibrated and the temperature deviation value are combined to obtain the temperature correction value of the flexible temperature sensor to be calibrated. Then compare the temperature correction value of the flexible temperature sensor to be calibrated with the temperature value of the standard temperature sensor to obtain the final indication error and complete the calibration.

[0036] like Figure 4 As shown in the figure, it is an experimental platform built by the present application for temperature compensation of flexible temperature sensors. The temperature compensation model used in the experiment is a trigonometric least squares fitting model. The temperature correction value of the flexible temperature sensor to be calibrated after compensation is compared with the temperature value of the standard temperature sensor, and the calculation result is the indication error. It is used to solve the technical problem of low temperature calibration accuracy caused by the vibration generated by the engine of the power system during operation.

[0037] The flexible temperature sensor temperature compensation device includes a small exciter 401, a metal heat conductive sheet 402, a vibration sensor 403, a flexible temperature sensor to be calibrated 404 (i.e., a second flexible temperature sensor to be calibrated), a temperature equalizing block 405, a dry body furnace 406, a standard temperature sensor 407 (i.e., a second standard temperature sensor) and a cantilever beam 408.

[0038] The small vibrator 401 is horizontally fixed on the free end of the cantilever beam 408; the small vibrator 401 and one side of the upper end of the metal thermal conductive sheet 402 are attached and fixedly connected, and the small vibrator 401 provides a stable vibration frequency and amplitude to the metal thermal conductive sheet 402 when in operation; the vibration sensor 403 is attached to one side of the lower end of the metal thermal conductive sheet 402 on one side; the flexible temperature sensor 404 to be calibrated is attached to the other side of the lower end of the metal thermal conductive sheet 402 on one side; the temperature equalizing block 405 is placed in the dry body furnace 406; the lower end of the metal thermal conductive sheet 402 is connected to the temperature equalizing block 405; the dry body furnace 406 provides a stable temperature source for the entire device; the cantilever beam 408 is horizontally placed on one side of the dry body furnace 406, serving as a fixed support base for the small vibrator 401.

[0039] The embodiment of the present application also provides an in-situ calibration temperature compensation method for a flexible temperature sensor in a laboratory, comprising:

[0040] The parameters of the small vibrator 401 are set to the vibration frequency T and the amplitude A. The temperature of the dry body furnace 406 is set to t0, and the temperature value t1 of the standard temperature sensor at this moment can be obtained. The small vibrator 401 is started, and the vibration sensor 403 measures the vibration frequency and amplitude at the current moment. Under the action of the small vibrator 401, the temperature value t2 of the flexible temperature sensor to be calibrated is obtained.

[0041] When the small vibration exciter 401 starts to operate, at a stable frequency T and amplitude A, the amount of vibration caused is:

[0042]

[0043] Since the change in temperature value caused by vibration is a nonlinear change, the linear least squares method is not considered to fit the data in this example. In this example, the trigonometric function method is used to fit the data. The trigonometric function method is used to fit N groups of data to obtain the trigonometric function expression:

[0044]

[0045] The temperature compensation algorithm uses the least square method of trigonometric functions. First, N sets of data (Δf, Δt i)(i=1,2,3……N); secondly, determine the fitting function expression; finally, calculate the output value after temperature compensation according to the obtained expression; wherein N is a positive integer greater than or equal to 2, Δf is the vibration parameter at the current moment, ΔR is the obtained resistance deviation value, and a0, a1, and a2 are fitting coefficients.

[0046] The resistance deviation value can be obtained by the corresponding temperature deviation value through the function correspondence formula of the temperature value:

[0047]

[0048] The corrected temperature value of the flexible temperature sensor to be calibrated is:

[0049]

[0050] The final indication error of the flexible temperature sensor obtained in the laboratory is:

[0051]

[0052] like Figure 5 Shown is a schematic diagram of the installation of the vibration sensor and the temperature sensor when the present application is subjected to on-site in-situ calibration. As shown in the left figure, the heat insulation cover 502 is fixed to the surface of the engine 501 of the equipment power system, and the vibration sensor 503 is fixed inside the heat insulation cover 502. The heat insulation cover 502 is made of a heat-insulating and rigid material. The heat insulation material can effectively isolate the heat emitted by the engine from affecting the vibration sensor; the rigid material can maintain a good effect on the transmission of engine vibration. As shown in the right figure, the temperature sensor 504 is fixed to the surface of the equipment power system 501, and the heat insulation cover 505 is fixed to the surface of the temperature sensor 504 and wraps the other five surfaces of the temperature sensor. The heat insulation cover 505 is made of a heat-insulating material, which ensures that the flexible temperature sensor 504 is heated on one side.

[0053] After the vibration sensor and the standard temperature sensor are installed, they are connected to the in-situ calibration device of the present application, and the temperature value t of the flexible temperature sensor to be calibrated is obtained through the data collector 109. 测 , the temperature value of the standard temperature sensor t 标 and vibration parameters (frequency T and amplitude A). According to the compensation algorithm obtained in the laboratory, the temperature correction value of the field flexible temperature sensor can be obtained as follows:

[0054]

[0055] After calculation, the indication error on site is:

[0056]

[0057] The present application also provides a method for predicting the internal temperature of an engine of an equipment power system. The temperature prediction method can be based on the temperature correction value t of the flexible temperature sensor collected by the in-situ calibration device. ’ 测 , based on the temperature dynamic prediction model, the internal temperature of the engine of the equipment power system is predicted as an extended function of this device.

[0058] The steps of temperature prediction are:

[0059] Collect temperature correction values ​​of the flexible temperature sensors to be calibrated at multiple points on the surface of the engine of the equipment power system;

[0060] According to the collected temperature data, a dynamic prediction model of the internal temperature of the engine is established;

[0061] The temperature data collected from the engine of the equipment power system is input into the temperature dynamic prediction model to predict the internal temperature of the engine.

[0062] In the present application, the temperature correction value of the flexible temperature sensor to be calibrated on the surface of the power system engine can be input into the temperature dynamic prediction model, and then the internal temperature data of the power system engine at the current moment can be output through the temperature dynamic prediction model. The internal temperature of the power system engine can be accurately output through the temperature dynamic prediction model by taking the temperature data of at least two temperature sampling points on the surface of the power system engine as input.

[0063] According to the physical relationship, the influencing factors of the internal temperature data of the engine of the equipment power system are analyzed, and the model formula is established according to the corresponding relationship between the temperature correction value of the flexible temperature sensor to be calibrated and the internal temperature of the engine of the equipment power system.

[0064] The model formula can be shown as follows:

[0065]

[0066] Among them, S i is the current internal temperature of the power system engine, A i is the temperature correction value of the flexible temperature sensor to be calibrated at different points of the engine of the power system, and a is the fitting coefficient of the model formula.

[0067] like Figure 6 As shown, it is a flow chart of the present application, comprising the following steps:

[0068] Step 1) In the laboratory, complete the simulation of the equipment power system engine calibration, and obtain a suitable temperature compensation algorithm based on the simulation of different vibration states to improve the calibration accuracy of the flexible temperature sensor.

[0069] Step 2) The calibration staff takes the in-situ calibration device to the site for calibration. Take out the standard temperature sensor 114 and vibration sensor 113 in the device and Figure 5 As shown, it is installed on the engine of the power system of the equipment, open the cover of the in-situ calibration device, rotate the power knob 111, and press the start-stop switch 112 to connect the above sensor to the USB interface 108 of the in-situ calibration device. Touch the industrial control computer 102, select the calibration plan, click the calibration plan, and wait for the calibration result.

[0070] Step 3) After completing the work according to the above steps and confirming that there are no errors, the system collects temperature measurement values ​​at multiple temperature calibration points and calculates the indication error, and displays the entire temperature change process in the form of a chart.

[0071] The indication error of the flexible temperature sensor to be calibrated is:

[0072]

[0073] Step 4) After the calibration is completed, press the start-stop switch 112 again to shut down the system, rotate the power knob 111, remove the vibration sensor 113 and the standard temperature sensor 114, and put them back into the device, close the box cover, and the calibration is completed.

[0074] The embodiment of the present application also provides a power system temperature in-situ calibration system based on a flexible temperature sensor, comprising:

[0075] A data acquisition unit, used for acquiring vibration parameters, a temperature value of a first standard temperature sensor, and a temperature value of a first flexible temperature sensor to be calibrated;

[0076] A temperature deviation value acquisition unit, used to acquire a temperature deviation value caused by vibration according to vibration parameters and a temperature compensation fitting algorithm;

[0077] a temperature correction value acquisition unit, configured to combine the temperature value of the first temperature sensor to be calibrated and the temperature deviation value to obtain a temperature correction value of the first flexible temperature sensor to be calibrated;

[0078] The result output unit is used to compare the temperature correction value of the first flexible temperature sensor to be calibrated with the temperature value of the first standard temperature sensor to obtain the final indication error and complete the calibration.

[0079] An embodiment of the present application further provides a computer device, including a memory, a processor, and computer executable instructions stored in the memory and executable on the processor, wherein the processor implements the power system temperature in-situ calibration method when executing the instructions.

[0080] An embodiment of the present application further provides a computer storage medium, wherein the computer storage medium stores computer executable instructions, and when the computer executable instructions are executed, the method for in-situ calibration of power system temperature is implemented.

[0081] The technical solution of the present invention is not limited to the above-mentioned specific embodiments. All technical variations made according to the technical solution of the present invention fall within the protection scope of the present invention.

Claims

1. A method for in-situ calibration of power system temperature based on a flexible temperature sensor, characterized in that: Collecting vibration parameters, a temperature value of a first standard temperature sensor, and a temperature value of a first flexible temperature sensor to be calibrated; According to the vibration parameters and temperature compensation fitting algorithm, the temperature deviation value caused by vibration is obtained; Combining the temperature value of the first temperature sensor to be calibrated and the temperature deviation value to obtain a temperature correction value of the first flexible temperature sensor to be calibrated; Compare the temperature correction value of the first flexible temperature sensor to be calibrated with the temperature value of the first standard temperature sensor to obtain a final indication error, thereby completing the calibration; The temperature compensation fitting algorithm uses the trigonometric least squares method as shown below: ； Where Δ f is the vibration parameter at the current moment, Δ R To obtain the resistance deviation value, a 0 , a 1 , a 2 is the fitting coefficient; The corresponding temperature deviation value is obtained through the functional correspondence between the resistance deviation value and the temperature value.

2. The method for in-situ calibration of power system temperature based on flexible temperature sensor according to claim 1, characterized in that: The temperature compensation fitting algorithm is implemented based on a flexible temperature sensor temperature compensation device, which includes an exciter, a heat conducting sheet and a heating unit; The exciter is used to provide a stable vibration frequency and amplitude to the thermal conductive sheet; The heat conducting sheet is used to conduct the heat energy released by the heating unit; The heat conducting sheet is provided with a second flexible temperature sensor to be calibrated and a vibration sensor.

3. The method for in-situ calibration of power system temperature based on flexible temperature sensor according to claim 2 is characterized in that: One end of the exciter is fixed to the free end of the cantilever beam, and the other end is connected to the heating unit through a temperature-averaging block, on which a second standard temperature sensor is arranged.

4. A power system temperature in-situ calibration system based on a flexible temperature sensor, characterized in that: include: A data acquisition unit, used for acquiring vibration parameters, a temperature value of a first standard temperature sensor, and a temperature value of a first flexible temperature sensor to be calibrated; A temperature deviation value acquisition unit, used to acquire a temperature deviation value caused by vibration according to vibration parameters and a temperature compensation fitting algorithm; a temperature correction value acquisition unit, configured to combine the temperature value of the first temperature sensor to be calibrated and the temperature deviation value to obtain a temperature correction value of the first flexible temperature sensor to be calibrated; A result output unit is used to compare the temperature correction value of the first flexible temperature sensor to be calibrated with the temperature value of the first standard temperature sensor to obtain a final indication error and complete the calibration; The temperature compensation fitting algorithm uses the trigonometric least squares method as shown below: ； Where Δ f is the vibration parameter at the current moment, Δ R To obtain the resistance deviation value, a 0 , a 1 , a 2 is the fitting coefficient; The corresponding temperature deviation value is obtained through the functional correspondence between the resistance deviation value and the temperature value.

5. A power system temperature in-situ device based on a flexible temperature sensor, characterized in that: The device is integrated in a suitcase, and comprises an industrial control computer equipped with the power system temperature in-situ calibration system according to claim 4, a data collector, a vibration sensor and a first standard temperature sensor.

6. A power system temperature in-situ device based on a flexible temperature sensor according to claim 5, characterized in that: It is also equipped with multiple interfaces of the temperature sensor, including UART interface, RS485 interface, RS232 interface, One-Wire interface and USB interface; among them, there are one group of UART interface, RS485 interface, RS232 interface and One-Wire interface, and three groups of USB interface.

7. A computer device comprising a memory, a processor, and computer executable instructions stored in the memory and executable on the processor, characterized in that: When the processor executes the instructions, the method for in-situ temperature calibration of a power system according to any one of claims 1 to 3 is implemented.

8. A computer storage medium storing computer executable instructions, characterized in that: When the computer executable instructions are executed, the method for in-situ temperature calibration of a power system according to any one of claims 1 to 3 is implemented.

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