Optical fiber pressure sensor testing system and method

Abstract

The invention discloses a pressure sensor testing system and method, and belongs to the technical field of pressure sensing. The system comprises a pressure generation assembly, a buffer assembly and a test assembly, wherein the pressure generation assembly is used for providing initial high pressure; the buffer assembly is connected with the pressure generation assembly and the measurement assembly through an internal and external thread adapter, and provides stable stepping pressure for the measurement assembly by performing multi-stage buffer on initial pressure so as to realize test calibration of the optical fiber pressure sensor; the buffer assembly can prevent the to-be-tested sensor from being damaged by high-pressure impact, the whole system carries out pressure regulation and control by adjusting valves of the buffer assembly and the measuring assembly, pressure in the buffer chamber and the measuring chamber is monitored in real time, test calibration of the optical fiber pressure sensor under the condition that the sensor is effectively protected is achieved, and the test accuracy is improved. Meanwhile, the device has the advantages of being simple in structure and convenient to operate, and has good economic benefits and popularization value.

Description

Technical Field

[0001] The present invention relates to the technical field of pressure sensing, and in particular, to a test system and method for an optical fiber pressure sensor. Background Art

[0002] Optical fiber pressure sensors transmit signals through light and have natural electromagnetic interference resistance, and are widely used in strong electromagnetic environments such as spacecraft, power systems, and nuclear power plants. Existing pressure sensor test systems are complex in equipment and difficult to be compatible with optical fiber pressure sensors. At the same time, the pressurizing equipment cannot directly provide stable stepped pressure, and directly pressurizing the sensor by the pressure source during the test is likely to cause damage to the optical fiber pressure sensor. There is a need to provide a test system suitable for optical fiber pressure sensors for the test and calibration problems of optical fiber pressure sensors. Summary of the Invention

[0003] The present invention provides a test system and method for an optical fiber pressure sensor, which can solve the technical problems that the existing pressure sensor test system cannot be compatible with the optical fiber pressure sensor and is likely to cause damage to the sensor, and gives a test method suitable for the optical fiber pressure sensor.

[0004] To achieve the above object, the technical solution of the present invention is as follows:

[0005] An optical fiber pressure sensor test system includes a pressure generating component, a buffer component, and a measurement component. The pressure generating component is used to provide an initial high pressure; the buffer component is connected to the pressure generating component and the measurement component through an internal and external thread adapter, and provides a stable stepped pressure for the measurement component by performing multi-stage buffering on the initial pressure, so as to realize the test and calibration of the optical fiber pressure sensor;

[0006] The buffer component includes a first-stage buffer chamber and a second-stage buffer chamber connected in series. The first-stage buffer chamber is connected to the pressure generating component, and the second-stage buffer chamber is connected to the measurement component. Independent valves are provided between the two-stage buffer chambers, between the first-stage buffer chamber and the pressure generating component, and between the second-stage buffer chamber and the measurement component;

[0007] The measurement component includes a measurement chamber and a pressure relief valve. The internal gas cavity volume of the measurement chamber is smaller than the internal gas cavity volume of the buffer chamber; the optical fiber pressure sensor to be tested is fixed inside the measurement chamber and is connected to an external sensor demodulation module through an adapter and an optical fiber; the internal pressure of the measurement chamber is increased through the valve between the measurement chamber and the second-stage buffer chamber, and the internal pressure is reduced through the pressure relief valve.

[0008] Preferably, in the buffer assembly, the two buffer chambers are identical hollow spherical structures with an internal air cavity. The surface of the hollow spherical structure is provided with three threaded holes communicating with the internal air cavity. The first threaded hole of the first-stage buffer chamber is connected to the pressure generating assembly through an internal-external thread adapter and an extension pipe. A first-stage valve is provided on the extension pipe to control the on-off of the gas path. The second threaded hole of the first-stage buffer chamber is connected to the first threaded hole of the second-stage buffer chamber through an internal-external thread adapter and an extension pipe. A second-stage valve is provided on the extension pipe between the two-stage buffer chambers to adjust the air pressure in the two-stage buffer chambers. Standard pressure gauges for real-time monitoring of the internal pressure of the buffer chambers are installed at the third threaded holes of the two buffer chambers. The third threaded hole of the second-stage buffer chamber is connected to the test assembly.

[0009] Preferably, the measuring assembly is a hollow spherical structure with an internal air cavity. The surface of the hollow spherical structure is provided with four threaded holes communicating with the internal air cavity. The first threaded hole of the measuring chamber is connected to the buffer assembly through an internal-external thread adapter and an extension pipe. A third-stage valve for positively adjusting the air pressure in the measuring chamber is provided on the extension pipe. The second and third threaded holes of the measuring chamber are respectively connected to a pressure relief valve for negatively adjusting the air pressure in the measuring chamber and a test optical fiber pressure sensor adapter. A standard pressure gauge for real-time monitoring of the internal pressure of the measuring chamber is installed at the fourth threaded hole.

[0010] Preferably, a washer seat for installing a rubber washer is provided at the bottom of the threaded hole of the hollow spherical structure.

[0011] Preferably, the measuring chamber is connected to the test optical fiber pressure sensor through the test optical fiber pressure sensor adapter.

[0012] Preferably, the valve is a two-way valve, and the air pressure is adjusted or the gas path is blocked by rotating the valve.

[0013] Preferably, the pressure generating assembly includes a pressure pump that outputs pressure through an output pipe. The end of the output pipe is a pressure output threaded joint for connecting the buffer assembly.

[0014] The beneficial effects of the present invention are as follows:

[0015] The present invention provides a simple optical pressure sensor test and calibration system, which can provide a stable step pressure to the optical fiber pressure sensor to protect the optical fiber pressure sensor from being damaged by sudden pressure shocks, and realize the test and calibration of the optical fiber pressure sensor. It has the characteristics of simple equipment, simple operation, and strong compatibility, and has good economic benefits and popularization value. Description of the Drawings

[0016] Figure 1Schematic diagram of the pressure sensor test system proposed by the present invention;

[0017] Figure 2 Schematic diagram of the buffer component of the present invention;

[0018] Figure 3 Schematic diagram of the measurement component of the present invention;

[0019] Figure 4 Cross-sectional view of the buffer chamber of the present invention;

[0020] Figure 5 Cross-sectional view of the measurement chamber of the present invention;

[0021] Figure 6 Cross-sectional view of the extension tube of the present invention;

[0022] In the figure: 1 - Pressure generating component, 101 - Pressure pump, 102 - Output pipe, 103 - Pressure output threaded joint, 2 - Buffer component, 201 - First - stage valve, 202 - First threaded joint, 203 - First - stage extension pipe, 204 - Second threaded joint, 205 - First standard pressure gauge, 206 - First - stage buffer chamber, 207 - Third threaded joint, 208 - Second - stage extension pipe, 209 - Fourth threaded joint, 210 - Second - stage valve, 211 - Fifth threaded joint, 212 - Third - stage extension pipe, 213 - Sixth threaded joint, 214 - Second standard pressure gauge, 215 - Second - stage buffer chamber, 216 - Seventh threaded joint, 217 - Fourth - stage extension pipe, 218 - Eighth threaded joint, 219 - Third - stage valve, 220 - First - stage valve gasket, 221 - First extension pipe gasket, 222 - Second extension pipe gasket, 223 - First buffer chamber gasket, 224 - First standard pressure gauge gasket, 225 - First standard pressure gauge adapter, 226 - Second buffer chamber gasket, 227 - Third buffer chamber gasket, 228 - Third extension pipe gasket, 229 - Fourth extension pipe short flange, 230 - Second - stage valve gasket, 231 - Third - stage valve gasket, 232 - Fifth extension pipe gasket, 233 - Sixth extension pipe gasket, 234 - Fourth buffer chamber gasket, 235 - Second standard pressure gauge gasket, 236 - Second standard pressure gauge adapter, 237 - Fifth buffer chamber gasket, 238 - Sixth buffer chamber gasket, 239 - Seventh extension pipe gasket, 240 - Eighth extension pipe gasket, 241 - Fourth valve gasket, 242 - Buffer chamber internal thread, 243 - Buffer chamber gasket seat, 244 - Buffer inner chamber, 245 - Extension pipe internal thread, 246 - Extension pipe gasket seat, 247 - Extension pipe through - hole, 3 - Measuring component, 301 - Ninth threaded adapter, 302 - Fifth - stage extension pipe, 303 - Tenth threaded adapter, 304 - Measuring chamber, 305 - Third standard pressure gauge, 306 - Test fiber optic pressure sensor adapter, 307 - Eleventh threaded adapter, 308 - Sixth - stage extension pipe, 309 - Optical fiber, 310 - Twelfth threaded adapter, 311 - Air - release valve, 312 - Sensor demodulation module, 313 - Fifth valve gasket, 314 - Ninth extension pipe gasket, 315 - Tenth extension pipe gasket, 316 - First measuring chamber gasket, 317 - Third standard pressure gauge gasket, 318 - Third standard pressure gauge adapter, 319 - Second measuring chamber gasket, 320 - Third measuring chamber gasket, 321 - Fourth measuring chamber gasket, 322 - Eleventh extension pipe gasket, 323 - Twelfth extension pipe gasket, 324 - Air - release valve gasket, 325 - Measuring chamber internal thread, 326 - Measuring chamber gasket seat, 327 - Test sensor interface, 328 - Measuring chamber inner chamber. Detailed implementation mode

[0023] The following will describe the technical solutions in the embodiments of the present invention completely and clearly in conjunction with the accompanying drawings.

[0024] In view of the test and calibration problems of fiber optic pressure sensors, the present invention provides a pressure sensor test system as shown in Figure 1 Figure 5, which includes a pressure generating component 1, a buffer component 2, and a measuring component 3. The pressure generating component is used to provide an initial high pressure; the buffer component is connected to the pressure generating component and the measuring component through an internal and external thread adapter, and provides a stable step pressure for the measuring component by performing multi-stage buffering on the initial pressure, so as to realize the test and calibration of the fiber optic pressure sensor.

[0025] The pressure generating component includes a pressure pump 101, which outputs pressure through an output pipe 102. The end of the output pipe 102 is a pressure output threaded joint 103, which is connected to the internal thread of the first-stage valve 201.

[0026] As shown in Figure 2 Figure 13, the buffer component is composed of a first-stage buffer chamber 206, a second-stage buffer chamber 215, a first-stage valve 201, a second-stage valve 210, a third-stage valve 219, a first standard pressure gauge 205, a second standard pressure gauge 214, and corresponding connecting components. The first-stage buffer chamber 206 is connected to the first-stage valve 203 through a second threaded joint 204, a first-stage extension pipe 203, and a third threaded joint 204. By controlling the first-stage valve 201, the air pressure output by the pressure generating component 1 is transmitted to the first buffer chamber 206; a first-stage valve gasket 220 is provided between the first-stage valve 201 and the first threaded joint 202, a first-stage extension pipe gasket 221 is provided between the first extension pipe 203 and the first threaded joint 202, a second extension pipe gasket 222 is provided between the first extension pipe 203 and the third threaded joint 204, and a first buffer chamber gasket 223 is provided between the first buffer chamber 206 and the second threaded joint 204. The gaskets play a sealing role to prevent pressure leakage. By controlling the second-stage valve 210, the air pressure in the first-stage buffer chamber 206 is transmitted to the second-stage buffer chamber 215.

[0027] The present invention uses a standard pressure gauge to measure the air pressure value in the first buffer chamber. In this embodiment, the first standard pressure gauge 205 is connected to the first-stage buffer chamber 206 through a first standard pressure gauge adapter 225. The bottom of the first standard pressure gauge has an external thread, the thread specification is M10×1.5, and the thread depth is 12 mm. A first standard pressure gauge gasket 224 is provided between the first standard pressure gauge 205 and the first standard pressure gauge adapter 225, and a second buffer chamber gasket 226 is provided between the first standard pressure gauge adapter 225 and the first-stage buffer chamber 206. The gaskets play a role in sealing the air path. The first standard pressure gauge 205 monitors the internal air pressure of the first-stage buffer chamber 206 in real time.

[0028] The first buffer chamber 206 and the second buffer chamber 215 are connected by a second-stage extension pipe 208, a second-stage valve 210, and a third-stage extension pipe 212. The second-stage extension pipe 208 is connected to the first-stage buffer chamber through a third threaded joint 207 and to the second-stage valve 210 through a fourth threaded joint 209. A third-stage buffer chamber gasket 227 is provided between the first buffer chamber 206 and the third threaded joint 207, a third buffer chamber gasket 228 is provided between the third threaded joint 207 and the second extension pipe 208, a fourth extension pipe gasket 229 is provided between the third-stage threaded pipe 208 and the fourth threaded joint 209, and a second-stage valve gasket 230 is provided between the fourth threaded joint 209 and the second-stage valve 210. The third-stage extension pipe 212 is connected to the second-stage valve 210 through a fifth threaded joint 211 and to the second buffer chamber 215 through a sixth threaded joint 213. A third-stage valve gasket 231 is provided between the second-stage valve 210 and the fifth threaded joint 211, a fifth extension pipe gasket 232 is provided between the fifth threaded joint 211 and the third-stage extension pipe 212, a sixth extension pipe gasket 233 is provided between the third-stage extension pipe 212 and the sixth threaded joint 213, and a fourth buffer chamber gasket 234 is provided between the sixth threaded joint 213 and the second-stage buffer chamber 215. The gaskets serve to seal the gas path.

[0029] The present invention uses a standard pressure gauge to measure the air pressure value in the second buffer chamber. In this embodiment, the second standard pressure gauge 214 is connected to the second-stage buffer chamber 215 through a second standard pressure gauge adapter 236. The bottom of the second standard pressure gauge has an external thread with a thread specification of M10×1.5 and a thread depth of 12 mm. A second standard pressure gauge gasket 235 is provided between the second standard pressure gauge 214 and the second standard pressure gauge adapter 236, and a fifth buffer chamber gasket 237 is provided between the second standard pressure gauge adapter 236 and the second-stage buffer chamber 215. The gaskets serve to seal the gas path. The second standard pressure gauge 214 monitors the internal air pressure of the second-stage buffer chamber 215 in real time.

[0030] The second-stage buffer chamber 215 and the third-stage valve 219 are connected by a fourth-stage extension pipe 217. The second-stage buffer chamber 215 and the fourth-stage extension pipe 217 are connected by a seventh threaded joint 216, and the fourth-stage extension pipe 217 and the third-stage valve 219 are connected by an eighth threaded joint 218. A sixth buffer chamber gasket 238 is provided between the second-stage buffer chamber 215 and the seventh threaded joint 216, a seventh extension pipe gasket 239 is provided between the seventh threaded joint 216 and the fourth extension pipe 217, an eighth extension pipe gasket 240 is provided between the seventh extension pipe 217 and the eighth threaded joint 218, and a fourth valve gasket 241 is provided between the eighth threaded joint 218 and the third-stage valve. The gaskets serve to seal the gas path. By controlling the third-stage valve 219, the air pressure in the second-stage buffer chamber 215 is transmitted to the measuring assembly 3.

[0031] In a specific implementation of the present invention, the cross-sectional structure of the buffer chamber is as Figure 4 shown, including a buffer inner chamber 244, three channels communicating with the buffer inner chamber 244, and each channel is provided with a buffer chamber internal thread 242, and a buffer chamber gasket seat 243 is provided at the bottom of each channel. Preferably, the bottom surface of the buffer chamber with a hollow spherical structure is a plane, with an outer diameter of 8 cm, an inner diameter of 3 cm, the thread specification of the three thread interfaces on the surface is M10×1.5, and the thread depth is 12 mm. The material of the buffer chamber is steel.

[0032] In a specific implementation of the present invention, the cross-sectional structure of the extension pipe is as Figure 6 shown, which is a hollow cylindrical structure, including an extension pipe through hole 247 and channels communicating with both ends of the extension pipe through hole 247. Each channel is provided with an extension pipe internal thread 245, and an extension pipe gasket seat 246 is provided at the bottom of each channel. The outer diameter of the hollow cylindrical structure is 2.5 cm, the inner diameter is 0.6 cm, the length is 5 cm, the internal thread specification of the two threaded holes at both ends is M10×1.5, and the thread depth is 12 mm. There is a gasket seat at the bottom of the internal thread for placing a rubber gasket. Further preferably, the material of the extension pipe is steel, which can be connected to the adapter to extend the gas path and prevent device interference.

[0033] As Figure 3As shown in the figure, the measurement component is composed of a measurement chamber 304, a third standard pressure gauge 305, a pressure relief valve 311, a fiber optic pressure sensor joint to be measured 306, a sensor demodulation module 312, and corresponding connection components. The measurement chamber 304 is connected to the buffer component 2 through a ninth threaded adapter 313, a fifth extension tube 302, and a tenth threaded adapter 303. A fifth valve gasket 313 is provided between the ninth threaded adapter 301 and the third-stage valve 219. A ninth extension tube gasket 314 is provided between the ninth threaded adapter 301 and the fifth extension tube 302. A tenth extension tube gasket 315 is provided between the fifth extension tube 302 and the tenth threaded adapter 303. A first measurement chamber gasket 316 is provided between the tenth threaded adapter 303 and the measurement chamber 304. The fiber optic pressure sensor to be measured is connected to the measurement chamber 304 through the fiber optic pressure sensor joint to be measured 306. A third measurement chamber gasket 320 is provided between the fiber optic pressure sensor joint to be measured 306 and the measurement chamber. The fiber optic pressure sensor joint to be measured 306 is connected to the sensor demodulation module 312 through the tail fiber 309 to demodulate the sensor to be measured and obtain the measurement value of the sensor for the calibration task.

[0034] The present invention uses a standard pressure gauge to measure the air pressure value in the measurement chamber. In this embodiment, the third standard pressure gauge 305 is connected to the measurement chamber 304 through a third standard pressure gauge adapter 318. A third standard pressure gauge gasket 317 is provided between the third standard pressure gauge 305 and the third standard pressure gauge adapter 318. A second measurement chamber gasket 319 is provided between the third standard pressure gauge adapter 318 and the measurement chamber 304. The gasket plays a role in sealing the air path. The third standard pressure gauge 305 monitors the internal air pressure of the measurement chamber 304 in real time and serves as a comparison reference for the fiber optic pressure sensor to be measured.

[0035] The pressure relief valve 311 is connected to the measurement chamber 304 through an eleventh threaded joint 307, a sixth-stage extension tube 308, and a twelfth threaded joint 310. A third measurement chamber gasket 321 is provided between the measurement chamber 304 and the eleventh threaded joint 307. An eleventh extension tube gasket 322 is provided between the eleventh threaded joint 307 and the sixth extension tube 308. A twelfth extension tube gasket 323 is provided between the sixth extension tube 308 and the twelfth threaded joint 310. A pressure relief valve gasket 324 is provided between the twelfth threaded joint 310 and the pressure relief valve 311. The gasket plays a sealing role. The measurement chamber is depressurized by controlling the pressure relief valve 311.

[0036] In a specific implementation of the present invention, the cross-sectional structure of the measurement chamber is as Figure 5As shown in the figure, it includes a measurement inner chamber 328, four channels communicating with the measurement inner chamber 328, and each channel is provided with an internal thread 325 in the measurement chamber. A washer seat 326 in the measurement chamber is provided at the bottom of each channel. One of the channels serves as the interface 327 for the sensor to be tested. Preferably, the bottom surface of the measurement chamber with a hollow spherical structure is a plane, with an outer diameter of 8 cm, an inner diameter of 1 cm, the thread specification of the four thread interfaces on the surface is M10×1.5, the thread depth is 12 mm, and the material of the buffer chamber is steel.

[0037] The valve adopted in the present invention is a two-way valve. Both ends are threaded holes, and there is a washer seat at the bottom of the holes for placing rubber washers. Further preferably, the material of the rubber ring is an O-ring made of nitrile rubber. The internal and external thread adapter is a hollow through structure. The external thread specification is M10×1.5, the length is 12 mm, the internal thread specification is M10×1.5, the thread depth is 12 mm, and there is a washer seat at the bottom of the internal thread for placing rubber washers. Preferably, the material of the internal and external thread adapter is steel.

[0038] When testing the fiber optic pressure sensor, the specific method is as follows:

[0039] S1, Connect the pressure generating component 1, the buffer component 2, and the measurement component 3 in the above manner. Fix the fiber optic pressure sensor to be tested with a range of X1 to X n MPa inside the measurement chamber, and connect it to the external sensor demodulation module through the adapter and the optical fiber. The sensor demodulation module is connected to the upper computer;

[0040] S2, Open the first-stage valve 201, close the second-stage valve 210, the third-stage valve 219, and the air release valve 311; Open the pressure pump 101 to provide an initial high pressure to the first-stage buffer chamber. Assume that the set air pressure is N MPa (N≥10), and observe the reading of the first standard pressure gauge 205. When the reading of the first standard pressure gauge 205 is greater than the set value, close the first-stage valve 201;

[0041] S3, Slightly rotate the second-stage valve 210, and close the other valves, so that the air pressure in the first-stage buffer chamber 206 slowly decreases, and the air pressure in the second-stage buffer chamber 215 slowly increases. Observe the reading of the second standard pressure gauge. When the reading of the second standard pressure gauge is N - 5 MPa (N - 5 MPa is greater than the maximum range of the fiber optic pressure sensor to be tested), close the second-stage valve 210;

[0042] S4, Divide several measurement points between X1 and X n and record them as X1, X2,…, X k ,…, X n ; Initialize the variable i = 1;

[0043] S5, slightly turn the third stage valve 219, and close the other valves, so that the air pressure in the measuring chamber 304 rises slowly, and observe the reading of the third standard pressure gauge 305. When the reading of the third standard pressure gauge is X i Mpa, close the third-stage valve 219, and record the data of the sensor to be tested on the host computer;

[0044] Determine whether i=n is true, if so, execute step S6, otherwise set i=i+1 and return to step S5;

[0045] S6, slightly turn the air release valve, and close the other valves, so that the pressure in the measuring chamber 304 slowly decreases, and observe the reading of the third standard pressure gauge 305. When the reading of the third standard pressure gauge is X i Mpa, close the air release valve 311, and record the data of the sensor to be tested on the host computer;

[0046] Determine whether i=1 is true, if so, execute step S7, otherwise set i=i-1 and return to step S6;

[0047] S7, calibrating the optical fiber pressure sensor according to the recorded upper computer reading and the corresponding indoor air pressure value of the measurement room.

[0048] The pressure regulation accuracy of the two-stage buffer assembly designed by the present invention is high. Through the step-by-step pressure reduction of the two-stage buffer chamber (the first-stage buffer chamber first stores the initial high pressure, and then slowly supplies air to the measuring chamber through the second-stage buffer chamber), the pressure can be controlled within a very small fluctuation range (such as the air pressure of the second-stage buffer chamber in step S3 is stabilized at N-5Mpa, avoiding measurement errors caused by sudden changes in pressure when the high-pressure gas source directly supplies air to the measuring chamber. The first-stage buffer chamber is first filled with an air pressure higher than the target value, and then the pressure is accurately reduced to a certain value through the second-stage buffer chamber, providing a stable intermediate pressure source for the subsequent fine pressure regulation of the measuring chamber, avoiding the high pressure directly acting on the measuring chamber and the sensor. The two-stage buffer chamber forms a dual buffer structure of "high-pressure storage-intermediate pressure stabilization", which can effectively isolate the pulse interference of the pressure generating assembly. The first-stage buffer chamber acts as a high-pressure isolation layer, so that the measuring chamber is only exposed to medium and low pressures after a certain pressure reduction. Even if the pressure generating assembly has short-term pressure fluctuations, the large-capacity gas storage characteristics of the first-stage buffer chamber can absorb the fluctuations and ensure the pressure stability of the second-stage buffer chamber.

[0049] The present invention adopts the optimal two-stage buffer design. Through the functional stratification of "high-pressure isolation layer (first stage) + precision pressure regulating layer (second stage)", the core requirement of "stable gas source → precision control" is achieved at the lowest hardware cost. It is especially suitable for precision testing scenarios such as optical fiber pressure sensors that are sensitive to small pressure changes. The present invention can flexibly cover different ranges (X1 to X2) by adjusting the pressure setting of the two-stage buffer chamber. n Mpa) sensor testing without frequent hardware replacement.

[0050] The specific embodiments of the present invention are only listed above. Obviously, the present invention is not limited to the above embodiments and there can be many variations. All variations that can be directly derived or associated by those of ordinary skill in the art from the disclosed content of the present invention shall be considered as the protection scope of the present invention.

Claims

1. An optical fiber pressure sensor test system, characterized in that, It includes a pressure generating component, a buffering component and a testing component. The pressure generating component is used to provide an initial high pressure. The buffering component is connected to the pressure generating component and the measuring component through an internal and external thread adapter. By performing multi-stage buffering on the initial pressure, it provides a stable step pressure for the measuring component to achieve the test calibration of the fiber optic pressure sensor. The buffering component includes a first-stage buffering chamber and a second-stage buffering chamber connected in series. The first-stage buffering chamber is connected to the pressure generating component, and the second-stage buffering chamber is connected to the testing component. Independent valves are provided between the two buffering chambers, between the first-stage buffering chamber and the pressure generating component, and between the second-stage buffering chamber and the testing component. The measuring component includes a measuring chamber and a pressure relief valve. The internal air chamber volume of the measuring chamber is smaller than that of the buffering chamber. The fiber optic pressure sensor to be tested is fixed inside the measuring chamber and is connected to an external sensor demodulation module through an adapter and an optical fiber. The measuring chamber increases the internal pressure through the valve between it and the second-stage buffering chamber and decreases the internal pressure through the pressure relief valve.

2. The fiber optic pressure sensor testing system according to claim 1, wherein The two buffering chambers in the buffering component are completely identical hollow spherical structures with an air chamber inside. There are three threaded holes on the surface of the hollow spherical structure that communicate with the internal air chamber. The first threaded hole of the first-stage buffering chamber is connected to the pressure generating component through an internal and external thread adapter and an extension tube. A first-stage valve is provided on the extension tube to control the on-off of the gas path. The second threaded hole of the first-stage buffering chamber is connected to the first threaded hole of the second-stage buffering chamber through an internal and external thread adapter and an extension tube. A second-stage valve is provided on the extension tube between the two buffering chambers to adjust the air pressure in the two buffering chambers. Standard pressure gauges for real-time monitoring of the internal pressure of the buffering chambers are installed at the third threaded holes of the two buffering chambers. The third threaded hole of the second-stage buffering chamber is connected to the testing component.

3. The fiber optic pressure sensor testing system according to claim 1, wherein The measuring component is a hollow spherical structure with an air chamber inside. There are four threaded holes on the surface of the hollow spherical structure that communicate with the internal air chamber. The first threaded hole of the measuring chamber is connected to the buffering component through an internal and external thread adapter and an extension tube. A third-stage valve for positively adjusting the air pressure in the measuring chamber is provided on the extension tube. The second and third threaded holes of the measuring chamber are respectively connected to a pressure relief valve for negatively adjusting the air pressure in the measuring chamber and an adapter for the fiber optic pressure sensor to be tested. A standard pressure gauge for real-time monitoring of the internal pressure of the measuring chamber is installed at the fourth threaded hole.

4. A fiber optic pressure sensor testing system according to claim 2 or 3, characterized in that, A washer seat for installing a rubber washer is provided at the bottom of the threaded hole of the hollow spherical structure.

5. The fiber optic pressure sensor testing system according to claim 3, wherein, The measuring chamber is connected to the fiber optic pressure sensor to be tested through an adapter for the fiber optic pressure sensor to be tested.

6. The fiber optic pressure sensor test system according to claim 1, characterized in that The valve is a two-way valve, and the air pressure is adjusted or the gas path is cut off by rotating the valve.

7. The fiber optic pressure sensor testing system according to claim 1, characterized in that, The pressure generating component includes a pressure pump (101) that outputs pressure through an output pipe (102). The end of the output pipe (102) is a pressure output threaded joint (103) for connecting the buffering component.

8. A testing method for the optical fiber pressure sensor testing system according to claim 1, characterized in that, It includes the following steps: (1) Fix the fiber optic pressure sensor to be measured with a range of X1 to X n Mpa inside the measurement chamber, connect it to the external sensor demodulation module through an adapter and optical fiber, and connect the sensor demodulation module to the upper computer to ensure the airtightness of all joints in the system; (2) Open the valve between the first - stage buffer chamber and the pressure - generating component, and close all other valves; turn on the pressure - generating component to provide an initial high pressure to the first - stage buffer chamber, and close the valve when the air pressure in the first - stage buffer chamber is greater than the set value of N Mpa; (3) Slightly turn the valve between the second - stage buffer chamber and the first - stage buffer chamber, and close all other valves, so that the air pressure in the first - stage buffer chamber slowly decreases and the air pressure in the second - stage buffer chamber slowly increases. When the air pressure in the second - stage buffer chamber rises to N - mMpa, close the valve, where N / 4 ≤ m ≤ N / 2; (4) Divide a number of measurement points between X1 and X n , denoted as X1, X2, …, X k , …, X n ; Initialize the variable i = 1; (5) Slightly turn the valve between the measurement chamber and the second-stage buffer chamber, and close all the other valves, so that the air pressure in the second-stage buffer chamber slowly decreases and the air pressure in the measurement chamber slowly increases until the air pressure in the measurement chamber rises to X i Mpa, then close the valve and record the reading of the upper computer; determine whether i = n holds. If so, execute step (6). Otherwise, let i = i + 1 and return to step (5); (6) Slightly rotate the pressure relief valve and close all other valves, so that the air pressure in the measurement chamber slowly decreases until the air pressure in the measurement chamber decreases to X i When the pressure reaches Mpa, close the valve and record the reading of the host computer; determine whether i = 1 holds. If so, execute step (7). Otherwise, set i = i - 1 and return to step (6); (7) Calibrate the fiber - optic pressure sensor according to the recorded readings of the host computer and the corresponding air pressure values in the measurement chamber.

9. The test method of the fiber - optic pressure sensor test system according to claim 8, characterized in that N - m is designed according to the range of the fiber - optic pressure sensor to be tested, and N - m needs to be greater than the maximum range of the sensor.

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