Thermoelectric response voltage peak value determination method of PVDF sensor

Abstract

The invention provides a method for determining a thermoelectric response voltage peak value of a PVDF (Polyvinylidene Fluoride) sensor. The method comprises the following steps: designing a test device for simulating an explosion impact test; in the model explosion impact test process, the waveform of a thermoelectric response voltage signal generated by the PVDF sensor and the waveform of a temperature signal collected by the instantaneous temperature sensor are displayed through the oscilloscope; selecting a mathematical function according to the waveform of the thermoelectric response voltage signal generated by the PVDF sensor to construct a mathematical formula for describing the waveform of the thermoelectric response voltage signal; obtaining a function expression for calculating a thermoelectric response voltage peak value by using a mathematical formula and a pyroelectric effect equation; and verifying the accuracy of the function expression until the calculated actual peak value of the thermoelectric response voltage and the theoretical peak value of the thermoelectric response voltage are smaller than a preset error value, and determining the peak value of the thermoelectric response voltage by using the function expression, so that the thermoelectric response voltage peak value of the PVDF sensor under different instantaneous high temperatures and measurement parameters can be rapidly and accurately determined.

Description

Technical Field

[0001] The present invention relates to the technical field of PVDF sensor testing, and particularly to a method for determining the peak value of the pyroelectric response voltage of a PVDF sensor. Background Art

[0002] A PVDF (polyvinylidene fluoride) sensor is a thin-film piezoelectric sensor, which has the advantages of fast response speed, wide pressure measurement range, and easy processing of various sizes, and has been widely used in the field of explosion shock pressure measurement. The measurement principle of a PVDF sensor mainly uses the piezoelectric effect of a PVDF piezoelectric film to convert the measured pressure into a voltage signal, thereby obtaining the magnitude of the explosion shock pressure. Since the PVDF piezoelectric film is a typical piezoelectric and pyroelectric polymer material, it not only has a piezoelectric effect but also a pyroelectric effect, that is, a change in temperature can cause a change in the polarization intensity of the pyroelectric material, thereby releasing a certain amount of induced charge.

[0003] In an explosion shock measurement experiment, the pressure pulse generated by the explosion of explosives is often accompanied by a temperature pulse at the same time. Therefore, when using a PVDF sensor to measure the explosion pressure, in addition to the charge generated by the piezoelectric effect, the PVDF sensor under the action of instantaneous high temperature also generates a certain amount of charge due to the pyroelectric effect. This part of the charge will inevitably be monitored by the test circuit at the same time and converted into a voltage signal, thus affecting the true voltage signal peak value of the measured explosion pressure and resulting in measurement errors in the experiment.

[0004] In order to correctly evaluate the influence of instantaneous high temperature on the measurement results of PVDF sensors in explosion shock tests, it is necessary to clarify the magnitude of the pyroelectric response voltage peak value of the PVDF sensor under the action of instantaneous high temperature during the test. When the pyroelectric response voltage peak value is small, the influence of temperature can be ignored; when the pyroelectric response voltage peak value is large, appropriate measures can be taken to reduce its pyroelectric response voltage peak value to meet the requirements of test accuracy.

[0005] The magnitude of the pyroelectric response voltage peak value of a PVDF sensor is affected by various factors such as the parameters of the test circuit, the magnitude of the temperature, and the action time. Moreover, the temperature action characteristics are very different at different measuring point positions from the explosion center, and the parameters of the test circuit used in different experiments also vary. These influencing factors make the methods for determining the pyroelectric response voltage peak value of a PVDF sensor through experiments or using pyroelectric equations in the past very cumbersome and complex. Summary of the Invention

[0006] The present invention provides a method for determining the peak value of the pyroelectric response voltage of a PVDF sensor, and its purpose is to be able to quickly and accurately determine the peak value of the pyroelectric response voltage of the PVDF sensor under different instantaneous high temperatures and measurement parameters.

[0007] To achieve the above object, the present invention provides a method for determining the peak value of the pyroelectric response voltage of a PVDF sensor, including:

[0008] Step 1: Design a test device for simulating an explosion shock test. The container of the test device is filled with a heat-conducting liquid. The PVDF sensor and the instantaneous temperature sensor are both placed in the heat-conducting liquid, and both the PVDF sensor and the instantaneous temperature sensor are electrically connected to an oscilloscope. A measurement circuit is connected between the PVDF sensor and the oscilloscope.

[0009] Step 2: During the process of the model explosion shock test, display the waveform of the pyroelectric response voltage signal generated by the PVDF sensor and the waveform of the temperature signal collected by the instantaneous temperature sensor through the oscilloscope to obtain the instantaneous temperature change value, the peak value of the pyroelectric response voltage, and the duration of the pyroelectric response.

[0010] Step 3: Select a mathematical function according to the waveform of the pyroelectric response voltage signal generated by the PVDF sensor, and construct a mathematical formula for describing the waveform of the pyroelectric response voltage signal based on the mathematical function.

[0011] Step 4: Substitute the mathematical formula for describing the waveform of the pyroelectric response voltage signal and the pyroelectric effect equation into the Kirchhoff current equation of the measurement circuit and perform transformation to obtain a function expression for calculating the peak value of the pyroelectric response voltage. The function expression is related to the instantaneous temperature change value, the duration of the pyroelectric response, the sensor area of the PVDF sensor, and the pyroelectric coefficient.

[0012] Step 5: By repeating Steps 2 to 4, change the parameters in the function expression or re-select the mathematical function to determine the accuracy of the function expression until the actual peak value of the pyroelectric response voltage calculated by the obtained function expression is less than the preset error value compared with the theoretical peak value of the pyroelectric response voltage, and then use this function expression to determine the peak value of the pyroelectric response voltage.

[0013] Furthermore, the test device for simulating the explosion shock test further includes:

[0014] A heating device, a general temperature sensor, and a temperature multimeter;

[0015] The container is placed on the heating device;

[0016] The general temperature sensor is electrically connected to the temperature multimeter;

[0017] The general temperature sensor is placed in the heat-conducting liquid.

[0018] Furthermore, the heating test method adopted by the test device for simulating the explosion shock test includes infrared heating, water bath oil bath heating, and physical heating.

[0019] Furthermore, the heating test methods adopted by the test device for simulating explosion shock tests include infrared heating, water bath and oil bath heating, and physical heating.

[0020] Furthermore, the measurement circuit includes:

[0021] a current source, a capacitor, a first resistor, and a second resistor;

[0022] The first end of the current source is connected to the first output end of the PVDF sensor, the first end of the capacitor, the first end of the first resistor, the first end of the second resistor, and the first input end of the oscilloscope;

[0023] The second end of the current source is connected to the second output end of the PVDF sensor, the second end of the capacitor, the second end of the first resistor, the second end of the second resistor, and the second input end of the oscilloscope.

[0024] Furthermore, the pyroelectric effect equation is:

[0025]

[0026] where I ρ represents the pyroelectric current, ρ represents the pyroelectric coefficient, A represents the sensor area, ΔT represents the instantaneous temperature change value, and t represents time.

[0027] Furthermore, substituting the mathematical formula for describing the waveform of the pyroelectric response voltage signal and the pyroelectric effect equation into the Kirchhoff's current equation of the measurement circuit and performing transformation includes:

[0028] Substituting the mathematical formula for describing the waveform of the pyroelectric response voltage signal and the pyroelectric effect equation into the Kirchhoff's current equation of the measurement circuit, the pyroelectric response expression of the PVDF sensor is obtained as:

[0029]

[0030] where C represents the sum of the capacitance values of the capacitor and the PVDF sensor in the measurement circuit, U(t) represents the negative voltage signal generated by the PVDF sensor under transient high temperature, and R represents the impedance of the oscilloscope;

[0031] Integrating the pyroelectric response expression, the integrated pyroelectric response expression is obtained as:

[0032]

[0033] Simplifying the integrated pyroelectric response expression, the result is:

[0034]

[0035] where V maxV represents the peak value of the pyroelectric response voltage, and T represents the duration of the pyroelectric response.

[0036] Furthermore, the functional expression for calculating the peak value of the pyroelectric response voltage is:

[0037]

[0038] where V max represents the peak value of the pyroelectric response voltage, and T represents the duration of the pyroelectric response.

[0039] The above solution of the present invention has the following beneficial effects:

[0040] By designing a test device for simulating explosion shock tests, the PVDF sensor and the instantaneous temperature sensor are both placed in the test device and electrically connected to an oscilloscope; during the model explosion shock test, the oscilloscope displays the waveform of the pyroelectric response voltage signal generated by the PVDF sensor and the waveform of the temperature signal collected by the instantaneous temperature sensor, obtaining the instantaneous temperature change value, the peak value of the pyroelectric response voltage, and the duration of the pyroelectric response; selecting a mathematical function based on the waveform of the pyroelectric response voltage signal generated by the PVDF sensor, and constructing a mathematical formula for describing the waveform of the pyroelectric response voltage signal based on the mathematical function; substituting the mathematical formula and the pyroelectric effect equation into the Kirchhoff current equation of the measurement circuit and performing transformation to obtain a functional expression for calculating the peak value of the pyroelectric response voltage; determining the accuracy of the functional expression by changing the parameters in the functional expression or reselecting the mathematical function until the actual peak value of the pyroelectric response voltage calculated by the obtained functional expression is less than the preset error value compared with the theoretical peak value of the pyroelectric response voltage, and then using this functional expression to determine the peak value of the pyroelectric response voltage, which can quickly and accurately determine the peak value of the pyroelectric response voltage of the PVDF sensor under different instantaneous high temperatures and measurement parameters, thereby quantitatively evaluating the influence of instantaneous high temperature on the test results of the PVDF sensor, and helping to further improve the test accuracy of the PVDF sensor in explosion shock tests.

[0041] Other beneficial effects of the present invention will be described in detail in the subsequent specific implementation part. Description of the Drawings

[0042] Figure 1 is a schematic flowchart of an embodiment of the present invention;

[0043] Figure 2 is a schematic diagram of the test device for simulating explosion shock tests of an embodiment of the present invention;

[0044] Figure 3 is the waveform diagram of the pyroelectric response voltage signal and the waveform diagram of the temperature signal in an embodiment of the present invention;

[0045] Figure 4Schematic diagram of the principle of the measurement circuit in the embodiments of the present invention;

[0046] Figure 5 Waveform diagram of the thermoelectric response voltage signal of the PVDF sensor at different instantaneous temperatures in the embodiments of the present invention.

[0047] Explanation of the reference numerals:

[0048] 1 - Heating device 2 - Container 3 - Heat-conducting liquid

[0049] 4 - PVDF sensor 5 - Instantaneous temperature sensor 6 - Ordinary temperature sensor. Specific embodiments

[0050] In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, the following will be described in detail with reference to the drawings and specific embodiments. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0051] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0052] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it can be a locking connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0053] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0054] The present invention provides a method for determining the peak value of the thermoelectric response voltage of a PVDF sensor for existing problems.

[0055] As Figures 1 - 3As shown in the figure, an embodiment of the present invention provides a method for determining the peak value of the pyroelectric response voltage of a PVDF sensor, including:

[0056] Step 1: Design a test device for simulating an explosion shock test. A heat-conducting liquid is injected into the container of the test device. The PVDF sensor and the instantaneous temperature sensor are both placed in the heat-conducting liquid, and both the PVDF sensor and the instantaneous temperature sensor are electrically connected to an oscilloscope. A measurement circuit is connected between the PVDF sensor and the oscilloscope.

[0057] Step 2: During the process of the model explosion shock test, display the waveform of the pyroelectric response voltage signal generated by the PVDF sensor and the waveform of the temperature signal collected by the instantaneous temperature sensor through the oscilloscope to obtain the instantaneous temperature change value, the peak value of the pyroelectric response voltage, and the duration of the pyroelectric response.

[0058] Step 3: Select a mathematical function according to the waveform of the pyroelectric response voltage signal generated by the PVDF sensor, and construct a mathematical formula for describing the waveform of the pyroelectric response voltage signal based on the mathematical function.

[0059] Step 4: Substitute the mathematical formula for describing the waveform of the pyroelectric response voltage signal and the pyroelectric effect equation into the Kirchhoff current equation of the measurement circuit and perform transformation to obtain a function expression for calculating the peak value of the pyroelectric response voltage. The function expression is related to the instantaneous temperature change value, the duration of the pyroelectric response, the sensor area and the pyroelectric coefficient of the PVDF sensor.

[0060] Step 5: By repeating Steps 2 to 4, change the parameters in the function expression or re-select the mathematical function to determine the accuracy of the function expression until the actual peak value of the pyroelectric response voltage calculated by the obtained function expression is less than the preset error value, and then use this function expression to determine the peak value of the pyroelectric response voltage.

[0061] It should be noted that the oscilloscope used in the embodiment of the present invention is a D3024 oscilloscope. The oscilloscope includes two groups of transmission channels. The internal resistance of the first group of transmission channels is set to 1 MΩ, and the internal resistance of the second group of transmission channels is set to 50 Ω. The measurement mode of the first group of transmission channels is the DC mode, and the measurement mode of the second group of transmission channels is the AC mode; wherein, the output end of the PVDF sensor 4 is connected to the first group of transmission channels CH1, and the output end of the instantaneous temperature sensor 5 is connected to the second group of transmission channels CH2 to form a test system; the performance parameters of the PVDF sensor 4 include the sensor area A, the capacitance value C p , the pyroelectric coefficient ρ, and the instantaneous temperature sensor 5 can be a temperature sensor with a fast response speed such as a K-type thermocouple that can record the instantaneous temperature waveform.

[0062] Specifically, the test device for simulating an explosion shock test further includes:

[0063] Heating device 1, ordinary temperature sensor 6, temperature multimeter;

[0064] The container 2 is placed on the heating device 1;

[0065] The ordinary temperature sensor 6 is electrically connected to the temperature multimeter;

[0066] The ordinary temperature sensor 6 is placed in the heat-conducting liquid 3.

[0067] In the embodiment of the present invention, the heat-conducting liquid 3 is dimethyl silicone oil or hot water, and the model of the temperature multimeter is UT89XE.

[0068] Specifically, the embodiment of the present invention also needs to determine the test method for the simulated explosion shock test. The heating test methods adopted include infrared heating, water bath oil bath heating, and physical heating. Among them, infrared heating transfers heat through the radiation of electromagnetic waves, water bath oil bath heating uses water or silicone oil as the heat-conducting liquid 3 and injects it into the container 2 for heating, and physical heating is to heat the heat-conducting liquid 3 in the heating container 2 through a flame. The container 2 is a stainless steel container.

[0069] Specifically, the mathematical function that can approximately describe the voltage signal waveform can be a trigonometric function, a sine function, or a Gaussian function.

[0070] Specifically, the instantaneous temperature sensor 5 is electrically connected to the oscilloscope through an amplifier circuit composed of an AD8495 amplifier chip.

[0071] Specifically, as Figure 4 shown, the measurement circuit includes:

[0072] Current source, capacitor Cc, first resistor Rc, second resistor Rs;

[0073] The first end of the current source is connected to the first output end of the PVDF sensor 4, the first end of the capacitor Cc, the first end of the first resistor Rc, the first end of the second resistor Rs, and the first input end of the oscilloscope;

[0074] The second end of the current source is connected to the second output end of the PVDF sensor 4, the second end of the capacitor Cc, the second end of the first resistor Rc, the second end of the second resistor Rs, and the second input end of the oscilloscope.

[0075] Specifically, the pyroelectric effect equation is:

[0076]

[0077] where I ρ represents the pyroelectric current, ρ represents the pyroelectric coefficient, A represents the sensor area, and the unit is m 2, ΔT represents the instantaneous temperature change value, with the unit of °C, and t represents time.

[0078] Specifically, substituting the mathematical formula for describing the waveform of the pyroelectric response voltage signal and the pyroelectric effect equation into the Kirchhoff's current equation of the measurement circuit and performing transformation, including:

[0079] Substituting the mathematical formula for describing the waveform of the pyroelectric response voltage signal and the pyroelectric effect equation into the Kirchhoff's current equation of the measurement circuit, the pyroelectric response expression of the PVDF sensor 4 is obtained as:

[0080]

[0081] Among them, C represents the sum of the capacitance Cc in the measurement circuit and the capacitance value C of the PVDF sensor 4, U(t) represents the negative voltage signal generated by the PVDF sensor 4 under transient high temperature, and R represents the impedance of the oscilloscope; p U(t) represents the negative voltage signal generated by the PVDF sensor 4 under transient high temperature, and R represents the impedance of the oscilloscope;

[0082] Integrating the pyroelectric response expression, the integrated pyroelectric response expression is obtained as:

[0083]

[0084] Simplifying the integrated pyroelectric response expression, we get:

[0085]

[0086] Among them, V max represents the pyroelectric response voltage peak value, and T represents the pyroelectric response duration.

[0087] Specifically, the function expression for calculating the pyroelectric response voltage peak value is:

[0088]

[0089] Among them, V max represents the pyroelectric response voltage peak value, and T represents the pyroelectric response duration.

[0090] In an embodiment of the present invention, the method for determining the pyroelectric response voltage peak value of the provided PVDF sensor 4 is further verified and illustrated in combination with specific test data, and the process is as follows:

[0091] Select the water bath heating method to heat the heat-conducting liquid 3 in the container 2 in the test device for simulating the explosion shock test to generate instantaneous high temperature. The test uses a PVDF sensor 4 with a specification of 10 mm square. Among them, the sensor area A of the PVDF sensor 4 is 1 cm 2 , the pyroelectric coefficient ρ is 3.1 nC·cm -2 ·K -1, the capacitance value C p is approximately 6.25 nF;

[0092] Connect both ends of the PVDF sensor 4 to the first set of transmission channels CH1 of the oscilloscope directly through the measurement circuit, and set the internal resistance R1 of this channel to 1 MΩ. Measure in the DC mode. Connect the instantaneous temperature sensor 5 to the second set of transmission channels CH2 of the oscilloscope directly through the amplifier circuit and measure in the AC mode to complete the construction of the test system;

[0093] During the model explosion shock test, first heat the temperature of the heat-conducting liquid 3 to 60 °C through the heating device 1, then quickly and steadily place the PVDF sensor 4 after waterproof sealing treatment and the instantaneous temperature sensor 5 together into the heat-conducting liquid 3 and then take them out quickly. The oscilloscope records the pyroelectric response voltage signal of the PVDF sensor 4 and the temperature signal recorded by the instantaneous temperature sensor 5 and generates the corresponding signal waveforms, as Figure 3 shown. The test results show that the instantaneous temperature change value ΔT is 41.5 °C, and the pyroelectric response peak value V max of the PVDF sensor 4 is approximately 0.98 V, and the pyroelectric signal duration T is about 300 ms;

[0094] According to Figure 3 the pyroelectric response voltage signal waveform shown, the test results show that the PVDF sensor 4 will generate a negative voltage signal similar to a "bell shape" in the pyroelectric response under the action of instantaneous high temperature. Therefore, select the sine function as the mathematical function, and then take the half-sine function in the sine function to approximately describe the pyroelectric response voltage signal generated by the PVDF sensor 4 according to the waveform of the negative voltage signal. Among them, the half-sine function can be expressed as:

[0095]

[0096] where U(t) represents the negative voltage signal generated by the PVDF sensor under transient high temperature, V max represents the pyroelectric response voltage peak value, with the unit of V, T represents the pyroelectric response duration, with the unit of s, t represents time, and the value range is 0 to T, with the unit of s.

[0097] According to the pyroelectric effect equation, the pyroelectric current generated by the PVDF sensor 4 under the pyroelectric response can be calculated;

[0098] According to the measurement circuit as Figure 4 shown, combined with Kirchhoff's current law, substitute the mathematical formula for describing the pyroelectric response voltage signal waveform and the pyroelectric effect equation into the Kirchhoff's current equation of the measurement circuit to obtain the pyroelectric response expression of the PVDF sensor 4;

[0099] Integrate the thermoelectric response expression to obtain the integrated thermoelectric response expression, simplify the integrated thermoelectric response expression to obtain the simplified thermoelectric response expression, and based on the simplified thermoelectric response expression, obtain the function expression for calculating the peak value of the thermoelectric response voltage;

[0100] In order to verify the accuracy of the function expression for calculating the peak value of the thermoelectric response voltage, several experiments are carried out in the embodiments of the present invention, and the experimental results are compared with the results calculated by the function expression for calculating the peak value of the thermoelectric response voltage. Three PVDF sensors 4 with a diameter of 20 mm are used in the experiment, and their capacitance C p is about 1.036 nF. Keeping other conditions unchanged, repeat the experimental operation described in step 2. Place the three PVDF sensors 4 in the heat-conducting liquid 3 at temperatures of 50 °C, 70 °C, and 90 °C respectively. The thermoelectric response signals of the PVDF sensors 4 under different instantaneous temperature change values ΔT are obtained in the experiment. As Figure 5 shown, where the temperature changes ΔT measured by the instantaneous temperature sensor 5 are 29 °C, 52 °C, and 71 °C respectively, and the pyroelectric signal duration T is about 300 ms. The peak values of the thermoelectric response voltages of the PVDF sensors 4 recorded in the experiment are -2.0 V, -3.4 V, and -5.3 V respectively;

[0101] According to the function expression for calculating the peak value of the thermoelectric response voltage, the thermoelectric response times of the PVDF sensors 4 under different instantaneous temperatures in the same experimental device are not much different. By estimating the thermoelectric response time T, when the instantaneous temperature changes ΔT are 29 °C, 52 °C, and 71 °C respectively, the peak values of the thermoelectric response voltages of the PVDF sensors 4 are -1.8 V, 3.2 V, and 4.8 V respectively. The errors between the calculation formulas and the experimental results are all within 10%. It can be shown that the function expression provided by the embodiments of the present invention can be used as the function expression for calculating and determining the peak value of the thermoelectric response voltage.

[0102] In an embodiment of the present invention, a test device for simulating an explosion shock test is designed, and both a PVDF sensor and an instantaneous temperature sensor are placed in the test device and electrically connected to an oscilloscope; during the process of the model explosion shock test, the oscilloscope is used to display the waveform of the pyroelectric response voltage signal generated by the PVDF sensor and the waveform of the temperature signal collected by the instantaneous temperature sensor, so as to obtain the instantaneous temperature change value, the voltage peak value of the pyroelectric response, and the pyroelectric response duration; a mathematical function is selected according to the waveform of the pyroelectric response voltage signal generated by the PVDF sensor, and a mathematical formula for describing the waveform of the pyroelectric response voltage signal is constructed based on the mathematical function; the mathematical formula and the pyroelectric effect equation are substituted into the Kirchhoff current equation of the measurement circuit and transformed to obtain a function expression for calculating the voltage peak value of the pyroelectric response; by changing the parameters in the function expression or reselecting the mathematical function to determine the accuracy of the function expression until the actual peak value of the pyroelectric response voltage calculated by the obtained function expression is less than a preset error value compared with the theoretical peak value of the pyroelectric response voltage, the function expression is used to determine the voltage peak value of the pyroelectric response, and the voltage peak value of the pyroelectric response of the PVDF sensor under different instantaneous high temperatures and measurement parameters can be determined quickly and accurately.

[0103] The above is the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for determining the peak value of the pyroelectric response voltage of a PVDF sensor, characterized in that, Including: Step 1: Design a test device for simulating explosion shock tests. A heat-conducting liquid is injected into the container of the test device. The PVDF sensor and the instantaneous temperature sensor are both placed in the heat-conducting liquid, and both the PVDF sensor and the instantaneous temperature sensor are electrically connected to an oscilloscope. A measurement circuit is connected between the PVDF sensor and the oscilloscope. Step 2: During the process of the model explosion shock test, display the waveform of the pyroelectric response voltage signal generated by the PVDF sensor and the waveform of the temperature signal collected by the instantaneous temperature sensor through the oscilloscope to obtain the instantaneous temperature change value, the voltage peak value of the pyroelectric response, and the pyroelectric response duration. Step 3: Select a mathematical function based on the waveform of the pyroelectric response voltage signal generated by the PVDF sensor, and construct a mathematical formula for describing the waveform of the pyroelectric response voltage signal based on the mathematical function. Step 4: Substitute the mathematical formula for describing the waveform of the pyroelectric response voltage signal and the pyroelectric effect equation into the Kirchhoff's current equation of the measurement circuit and perform transformation to obtain a function expression for calculating the voltage peak value of the pyroelectric response. The function expression is related to the instantaneous temperature change value, the pyroelectric response duration, the sensor area and the pyroelectric coefficient of the PVDF sensor. Step 5: By repeating steps 2 to 4, change the parameters in the function expression or re-select the mathematical function to determine the accuracy of the function expression until the actual peak value of the pyroelectric response voltage calculated by the obtained function expression is less than the preset error value compared with the theoretical peak value of the pyroelectric response voltage, and then use this function expression to determine the voltage peak value of the pyroelectric response.

2. The method for determining the peak value of the pyroelectric response voltage of the PVDF sensor according to claim 1, wherein The test device for the simulated explosion shock test further includes: Heating equipment, ordinary temperature sensor, temperature multimeter; The container is placed on the heating equipment; The ordinary temperature sensor is electrically connected to the temperature multimeter; The ordinary temperature sensor is placed in the heat-conducting liquid.

3. The method for determining the peak value of the pyroelectric response voltage of the PVDF sensor according to claim 2, characterized in that, The heating test method adopted by the test device for the simulated explosion shock test includes infrared heating, water bath oil bath heating, and physical heating.

4. The method for determining the peak value of the pyroelectric response voltage of the PVDF sensor according to claim 1, characterized in that, The mathematical function is a trigonometric function or a sine function or a Gaussian function.

5. The method for determining the peak value of the pyroelectric response voltage of the PVDF sensor according to claim 1, characterized in that The measurement circuit includes: Current source, capacitor, first resistor, second resistor; The first end of the current source is connected to the first output end of the PVDF sensor, the first end of the capacitor, the first end of the first resistor, the first end of the second resistor, and the first input end of the oscilloscope; The second end of the current source is connected to the second output end of the PVDF sensor, the second end of the capacitor, the second end of the first resistor, the second end of the second resistor, and the second input end of the oscilloscope.

6. The method for determining the peak value of the pyroelectric response voltage of the PVDF sensor according to claim 1, wherein The pyroelectric effect equation is: Among them, I ρ represents the pyroelectric current, ρ represents the pyroelectric coefficient, A represents the sensor area, ΔT represents the instantaneous temperature change value, and t represents time.

7. The method for determining the peak value of the pyroelectric response voltage of the PVDF sensor according to claim 6, characterized in that, Substituting the mathematical formula for describing the waveform of the pyroelectric response voltage signal and the pyroelectric effect equation into the Kirchhoff's current equation of the measurement circuit and performing transformation includes: Substitute the mathematical formula for describing the waveform of the pyroelectric response voltage signal and the pyroelectric effect equation into the Kirchhoff's current equation of the measurement circuit to obtain the pyroelectric response expression of the PVDF sensor as: Where C represents the sum of the capacitance in the measurement circuit and the capacitance value of the PVDF sensor, U(t) represents the negative voltage signal generated by the PVDF sensor under transient high temperature, and R represents the impedance of the oscilloscope; Integrating the thermoelectric response expression, the integrated thermoelectric response expression is obtained as follows: Simplifying the integrated thermoelectric response expression, we get: Among them, V max represents the peak value of the thermoelectric response voltage, and T represents the thermoelectric response duration.

8. The method for determining the peak value of the pyroelectric response voltage of the PVDF sensor according to claim 7, characterized in that, The function expression for calculating the peak value of the thermoelectric response voltage is: Among them, V max represents the peak value of the thermoelectric response voltage, and T represents the thermoelectric response duration.

Images