Auxiliary calibration system for testing performance of distributed optical fiber vibration sensing system

Abstract

The utility model discloses an auxiliary calibration system for testing the performance of a distributed optical fiber vibration sensing system, the calibration system comprises a quantitative vibration subsystem and a sound source subsystem, the quantitative vibration subsystem comprises an optical fiber port, a sensing optical fiber, a first piezoelectric ceramic and an electric signal input port; the sound source subsystem comprises a loudspeaker, a sensing optical fiber, a second piezoelectric ceramic, a central control panel and an interactive display screen. According to the utility model, verification of various indexes is integrated, a non-interference cabin is established through vibration isolation measures, and the background noise level of the distributed optical fiber vibration sensing system is tested; piezoelectric ceramics are used for constructing vibration signals with different waveforms, amplitudes, frequencies and different space intervals to assist in verifying technical indexes such as spatial resolution, frequency measurement range and the like of the distributed optical fiber vibration sensing system; a sound source cabin is established to assist the distributed optical fiber vibration sensing system in verifying the sound monitoring and restoring functions of the system.

Description

Technical Field

[0001] The utility model relates to a calibration tool, in particular to an auxiliary calibration system and method for testing the performance of a distributed optical fiber vibration sensing system. Background Art

[0002] Distributed fiber optic vibration sensing systems use optical fibers to sense external disturbances, and accurately locate the disturbance position and quantitatively describe the disturbance by demodulating the scattered light signal in the optical fiber affected by the external disturbance. They are widely used in oil and gas well exploration and perimeter security. Noise level, spatial resolution, measurement frequency range, etc. are key technical indicators for measuring the performance of distributed fiber optic vibration sensing systems. Understanding a set of key technical indicators of a distributed fiber optic vibration sensing system is of great guiding significance for determining its specific application scenarios. So far, many distributed fiber optic vibration sensing systems have been established, but there is no dedicated auxiliary calibration system that integrates multiple indicator verifications to assist in testing the performance of distributed fiber optic vibration sensing systems and verify their reliability in practical applications. Utility Model Content

[0003] In order to solve the defects and shortcomings existing in the above-mentioned prior art and meet the market demand for technical indicator measurement and reliability verification of distributed optical fiber vibration sensing systems, the utility model provides a system that integrates multiple indicator verifications, establishes an interference-free cabin through vibration isolation measures, and tests the background noise level of the distributed optical fiber vibration sensing system; uses piezoelectric ceramics to construct vibration signals with different waveforms, amplitudes, frequencies and different spatial spacings to assist in verifying technical indicators such as spatial resolution and frequency measurement range of the distributed optical fiber vibration sensing system; establishes a sound source cabin to assist the distributed optical fiber vibration sensing system in verifying its sound monitoring and restoration functions, and is an auxiliary calibration system for testing the performance of the distributed optical fiber vibration sensing system.

[0004] The purpose of the utility model is achieved through the following technical solutions: an auxiliary calibration system for testing the performance of a distributed optical fiber vibration sensing system, which is concentrated in a tool box with a handle and a regular rectangular shape, and includes a quantitative vibration subsystem and a sound source subsystem;

[0005] The quantitative vibration subsystem establishes a quantitative vibration scenario for testing the performance of the distributed optical fiber vibration sensing system and assists in calibration work, and includes an optical fiber port, a sensing optical fiber, a No. 1 piezoelectric ceramic, and an electrical signal input port;

[0006] The sound source subsystem is responsible for playing the sound source externally, creating a simulation scene for realizing the monitoring function of the optical fiber vibration sensor system, which includes No. 2 piezoelectric ceramics, sensing optical fiber, speakers, central control panel and interactive display screen;

[0007] The interior of the toolbox is filled with vibration isolation components that cooperate with the quantitative vibration subsystem and the sound source subsystem to prevent external vibration signals from interfering with the internal vibration environment.

[0008] Preferably, the optical fiber port is connected to the optical fiber output by the distributed optical fiber vibration sensing system outside the calibration system; the sensing optical fiber is placed inside the calibration system to sense the quantitative vibration signal and the external sound source.

[0009] Preferably, the sensing optical fiber is tightly wound around piezoelectric ceramic No. 1, and the piezoelectric ceramic No. 1 is connected to the electrical signal input port, and the electrical signal input port is connected to an external signal generator. The piezoelectric ceramic No. 1 receives the quantitative vibration electrical signal from the signal generator and converts it into a quantitative mechanical vibration signal. The generated mechanical vibration signal is sensed by the sensing optical fiber.

[0010] Preferably, the piezoelectric ceramic No. 1 is used to generate a vibration signal of a specified waveform, a specified amplitude and a specified frequency, and is entangled and coupled with the sensing optical fiber No. 1; by setting vibration signals of different waveforms and frequencies and setting the spatial distances between different piezoelectric ceramics, a variety of quantitative vibration scenes are created.

[0011] Preferably, the speaker is used to play the sound source specified by the user through the interactive display screen; the central control panel is responsible for storing and controlling the playback of the sound source; the No. 2 piezoelectric ceramic is entangled and coupled with the sensing optical fiber to receive the external sound signal from the speaker.

[0012] Preferably, the No. 2 piezoelectric ceramic and the speaker are placed in a sound source subsystem cabin surrounded by sound-absorbing cotton to prevent echoes when the sound is played outside.

[0013] Preferably, the quantitative vibration subsystem establishes a quantitative vibration scenario for testing the performance of the distributed optical fiber vibration sensing system, mainly referring to: providing quantitative vibration signals with different spatial spacings for optical fiber sensing, including but not limited to inputting electrical signals into piezoelectric ceramics to generate quantitative mechanical vibrations, and setting up multiple piezoelectric ceramics with different spatial spacings.

[0014] A calibration method for an auxiliary calibration system for testing the performance of a distributed optical fiber vibration sensing system, the steps are as follows:

[0015] After the S1 auxiliary calibration system was subjected to vibration isolation treatment, a quiet and stable noise measurement environment was established. Without inputting any vibration signal into the quantitative vibration subsystem, the background noise level test of the distributed optical fiber vibration sensing system was carried out.

[0016] S2 inputs vibration signals of different waveforms, frequencies and amplitudes into the quantitative vibration subsystem, inputs electrical signals of different waveforms, frequencies and amplitudes into the piezoelectric ceramics, and sets the piezoelectric ceramics at a certain spatial distance to test and verify the technical indicators of the distributed optical fiber vibration sensing system;

[0017] S3 selects to play a specific sound source in the sound source subsystem to test the sound monitoring and restoration functions of the distributed optical fiber vibration sensing system.

[0018] Preferably, the step S1 specifically refers to: when conducting a background noise level test of a distributed optical fiber vibration sensing system, a quiet and stable noise measurement environment needs to be established, and the auxiliary calibration system itself has been placed in vibration isolation cotton for vibration isolation treatment. At this time, the four PZTs do not input any electrical signals, and the speakers in the sound source subsystem are turned off to observe the background noise level of the distributed optical fiber vibration sensing system.

[0019] Preferably, the technical indicators of the distributed optical fiber vibration sensing system tested and verified in step S2 specifically include:

[0020] 1) When testing the measurement accuracy of the distributed optical fiber vibration sensing system, a sinusoidal electrical signal of, for example, 100 mV 100 Hz is input into four piezoelectric ceramics in the quantitative vibration subsystem to observe whether the distributed optical fiber vibration sensing system can detect a sinusoidal vibration signal of 100 Hz at the corresponding sensing distance;

[0021] 2) When testing the spatial resolution of the distributed fiber optic vibration sensing system, a 100mV 100Hz sinusoidal electrical signal is input into the three piezoelectric ceramics A, B, and C in the quantitative vibration subsystem, and the measurement results of the distributed fiber optic vibration sensing system are observed in two ways. 1: Set the distance between the piezoelectric ceramics B and C to 4m, and wrap 5m of sensing optical fiber around the piezoelectric ceramics B and C. Observe whether the vibration signals at the piezoelectric ceramics B and C on the sensing result distance curve can be clearly distinguished. If they can be distinguished, it proves that the system has a spatial resolution of 4m. 2: Set the distance between the piezoelectric ceramics A and B to 10m, and wrap 0.5m of sensing optical fiber around the piezoelectric ceramic A. According to the 3Db width rule (in the sensing distance dimension, the length corresponding to the vibration signal dropping to half of its peak value is the spatial resolution), observe whether the 3dB width of the vibration signal at the piezoelectric ceramic A is 4m. If it is 4m, it proves that the system has a spatial resolution of 4m.

[0022] 3) Test the linear relationship between the vibration signal amplitude measured by the distributed optical fiber vibration sensing system and the piezoelectric ceramic gain; input multiple groups of 100Hz sinusoidal electrical signals with different amplitudes, such as 50, 75, and 100mV, into the piezoelectric ceramic A in the quantitative vibration subsystem, and observe the linear relationship between the vibration signal amplitude measured by the distributed optical fiber vibration sensing system at the piezoelectric ceramic A and the piezoelectric ceramic gain.

[0023] The utility model integrates multiple index verifications in one, establishes an interference-free cabin through vibration isolation measures, and tests the background noise level of the distributed optical fiber vibration sensing system; uses piezoelectric ceramics to construct vibration signals with different waveforms, amplitudes, frequencies and different spatial spacings to assist in verifying the technical indicators of the distributed optical fiber vibration sensing system, such as spatial resolution and frequency measurement range; establishes a sound source cabin to assist the distributed optical fiber vibration sensing system in verifying its sound monitoring and restoration functions. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the internal structure of the utility model;

[0025] Figure 2 It is a structural schematic diagram of the utility model;

[0026] In the figure, 1. handle, 2. shell, 3. interactive display screen, 4. USB slot, 5. optical fiber port, 6. power slot, 7. vibration isolation cotton, 8. sensing optical fiber, 9. sound source subsystem cabin, 10. sound absorbing cotton, 11. speaker, 12. central control panel, 13. electrical signal input port, 14. piezoelectric ceramic No. 1, 15. piezoelectric ceramic No. 2. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0028] like Figure 1 and 2 As shown, an auxiliary calibration system for testing the performance of a distributed optical fiber vibration sensing system includes a quantitative vibration subsystem and a sound source subsystem. The auxiliary calibration system is assembled into a toolbox with a handle 1 and a regular rectangular shape 2. The toolbox is compact and easy to carry. The inside of the toolbox is filled with vibration isolation cotton 7 to prevent external vibration signals from interfering with the internal stable environment; a power slot 6 is provided on the outside of the toolbox for connecting to the mains or other power supplies; and a USB slot 4 is also provided on the outside of the toolbox for connecting to a USB signal line.

[0029] The quantitative vibration subsystem consists of an optical fiber port 5, a sensing optical fiber 8, an electrical signal input port 12, and three No. 1 piezoelectric ceramics 14. The optical fiber port 5 is connected to the optical fiber output by the distributed optical fiber vibration sensing system outside the calibration system. The sensing optical fiber is placed inside the calibration system to sense the quantitative vibration signal and the external sound source. The No. 1 piezoelectric ceramic 14 generates a vibration signal of a specified waveform, a specified amplitude, and a specified frequency, and is entangled and coupled with the sensing optical fiber. The No. 1 piezoelectric ceramic 14 is connected to the electrical signal input port, and the electrical signal input port is connected to an external signal generator. The No. 1 piezoelectric ceramic 14 receives the quantitative vibration electrical signal from the signal generator and converts it into a quantitative mechanical vibration signal. The generated mechanical vibration signal is sensed by the sensing optical fiber.

[0030] The sound source subsystem consists of No. 2 piezoelectric ceramic 15, sensor fiber 8, speaker 11, central control panel 12 and interactive display screen 3. The sound source subsystem is responsible for playing the sound source externally and establishing a simulation scene for realizing the monitoring function of the optical fiber vibration sensor system. The piezoelectric ceramic and speaker in the sound source subsystem are placed in a sound source subsystem cabin surrounded by sound-absorbing cotton to prevent echoes when the sound is played externally.

[0031] Combined with Figure 2 The calibration method is further explained with specific implementation examples.

[0032] 1) When conducting the background noise level test of the distributed optical fiber vibration sensing system, a quiet and stable noise measurement environment needs to be established. The auxiliary calibration system itself has been placed in vibration isolation cotton for vibration isolation treatment. At this time, the four piezoelectric ceramics (PZT) do not input any electrical signals, and the speakers in the sound source subsystem are turned off to observe the background noise level of the distributed optical fiber vibration sensing system.

[0033] 2) When testing the measurement accuracy of the distributed optical fiber vibration sensing system, a sinusoidal electrical signal of, for example, 100 mV and 100 Hz is input into three No. 1 piezoelectric ceramics (A, B, C) and one No. 2 piezoelectric ceramic (D) in the quantitative vibration subsystem to observe whether the distributed optical fiber vibration sensing system can detect a 100 Hz sinusoidal vibration signal at the corresponding sensing distance.

[0034] 3) When testing the spatial resolution of the distributed optical fiber vibration sensing system (taking 4m spatial resolution as an example), a 100mV 100Hz sinusoidal electrical signal is input into the three No. 1 piezoelectric ceramics A, B, and C in the quantitative vibration subsystem, and the measurement results of the distributed optical fiber vibration sensing system are observed in two ways. 1: Set the distance between the B and C piezoelectric ceramics to 4m, and wind 5m of sensing optical fiber on the B and C piezoelectric ceramics to observe whether the vibration signals at the B and C piezoelectric ceramics on the sensing result distance curve can be clearly distinguished. If they can be distinguished, it proves that the spatial resolution is 4m. 2: Set the distance between the A and B piezoelectric ceramics to 10m, and wind 0.5m of sensing optical fiber on the A piezoelectric ceramic. According to the 3Db width rule (in the sensing distance dimension, the length corresponding to the vibration signal dropping to half of its peak value is the spatial resolution), observe whether the 3dB width of the vibration signal at the A piezoelectric ceramic is 4m. If it is 4m, it proves that the spatial resolution is 4m.

[0035] 4) Test the linear relationship between the amplitude of the vibration signal measured by the distributed optical fiber vibration sensing system and the gain of the piezoelectric ceramic. In the quantitative vibration subsystem, multiple groups of 100Hz sinusoidal electrical signals with different amplitudes, such as 50, 75, and 100mV, are input into the piezoelectric ceramic No. 1 A, and the linear relationship between the amplitude of the vibration signal measured by the distributed optical fiber vibration sensing system at the piezoelectric ceramic No. 1 A and the gain of the piezoelectric ceramic is observed.

[0036] 5) Select a specific sound source to play in the sound source subsystem to test the sound monitoring and restoration functions of the distributed optical fiber vibration sensing system.

[0037] The above are only preferred specific implementation methods of the utility model, but the protection scope of the utility model is not limited to this. Any technician familiar with the technical field within the technical scope disclosed by the utility model, who makes equivalent replacements or changes based on the technical scheme and utility model concept of the utility model, should be covered by the protection scope of the utility model.

Claims

1. An auxiliary calibration system for testing the performance of a distributed optical fiber vibration sensing system, characterized in that: The calibration system is concentrated in a tool box with a handle and a regular rectangular shape, including a quantitative vibration subsystem and a sound source subsystem; The quantitative vibration subsystem establishes a quantitative vibration scenario for testing the performance of the distributed optical fiber vibration sensing system and assists in calibration work, and includes an optical fiber port, a sensing optical fiber, a No. 1 piezoelectric ceramic, and an electrical signal input port; The sound source subsystem is responsible for playing the sound source externally, creating a simulation scene for realizing the monitoring function of the optical fiber vibration sensor system, which includes No. 2 piezoelectric ceramics, sensing optical fiber, speakers, central control panel and interactive display screen; The interior of the toolbox is filled with vibration isolation components that cooperate with the quantitative vibration subsystem and the sound source subsystem to prevent external vibration signals from interfering with the internal vibration environment.

2. The auxiliary calibration system for testing the performance of a distributed optical fiber vibration sensing system according to claim 1, characterized in that: The optical fiber port is connected to the optical fiber output by the distributed optical fiber vibration sensing system outside the calibration system; the sensing optical fiber is placed inside the calibration system to sense the quantitative vibration signal and the external sound source.

3. The auxiliary calibration system for testing the performance of a distributed optical fiber vibration sensing system according to claim 2, characterized in that: The sensing optical fiber is tightly wound around piezoelectric ceramic No. 1, which is connected to the electrical signal input port, which is connected to an external signal generator. The piezoelectric ceramic No. 1 receives a quantitative vibration electrical signal from the signal generator and converts it into a quantitative mechanical vibration signal. The generated mechanical vibration signal is sensed by the sensing optical fiber.

4. The auxiliary calibration system for testing the performance of a distributed optical fiber vibration sensing system according to claim 3, characterized in that: The piezoelectric ceramic No. 1 is used to generate a vibration signal of a specified waveform, a specified amplitude and a specified frequency, and is entangled and coupled with the sensing optical fiber; by setting vibration signals of different waveforms and frequencies and setting the spatial distances between different piezoelectric ceramics, a variety of quantitative vibration scenes are created.

5. The auxiliary calibration system for testing the performance of a distributed optical fiber vibration sensing system according to claim 1, characterized in that: The speaker is used to play the sound source specified by the user through the interactive display screen; the central control panel is responsible for storing and controlling the playback of the sound source; the second piezoelectric ceramic is wound and coupled with the sensing optical fiber to receive the external sound signal from the speaker.

6. The auxiliary calibration system for testing the performance of a distributed optical fiber vibration sensing system according to claim 5, characterized in that: The No. 2 piezoelectric ceramic and the loudspeaker are placed in a sound source subsystem cabin which is surrounded by sound-absorbing cotton to prevent echo when the sound is played outside.

7. The auxiliary calibration system for testing the performance of a distributed optical fiber vibration sensing system according to claim 1, characterized in that: The quantitative vibration subsystem establishes a quantitative vibration scenario for testing the performance of the distributed optical fiber vibration sensing system, mainly referring to: providing quantitative vibration signals with different spatial spacing for optical fiber sensing, including but not limited to inputting electrical signals into piezoelectric ceramics to generate quantitative mechanical vibrations, and setting up multiple piezoelectric ceramics with different spatial spacings.

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