A method and system for vibration detection of a power transmission GIL conduit

Abstract

The application provides a vibration detection method and system of a power transmission GIL pipeline, which comprises the following steps: after sending a laser to an optical fiber, receiving a light signal reflected back in the optical fiber, the light signal being used to characterize the change of the light emitting intensity of the sensing optical cable along the length direction of the pipeline; photoelectrically converting the light signal to obtain an electric digital signal corresponding to the light emitting intensity; calculating the electric digital signal to obtain the vibration intensity of the pipeline at multiple positions along the length direction; and when the vibration intensity is greater than or equal to a first preset threshold, issuing an alarm indication, the alarm indication at least including the numerical value of the vibration intensity and the position corresponding to the vibration intensity. The method calculates the vibration information of the power transmission GIL pipeline through the change of the light emitting intensity, and further determines whether there is vibration abnormality through the vibration information, which not only realizes the all-round monitoring of the pipeline vibration condition, but also simplifies the operation and maintenance process, and does not affect the structure of the power transmission GIL pipeline.

Description

Technical Field

[0001] This application relates to the field of optical fiber vibration monitoring technology for power transmission pipelines, specifically to a vibration detection method and system for a power transmission GIL pipeline. Background Technology

[0002] Power transmission GIL pipelines are critical equipment for power plant electricity transmission. GIL failures can significantly impact power transmission reliability and cause substantial economic losses. The operation of power transmission GIL pipelines is gradually becoming more intelligent, relying on intelligent management and control platforms for intelligent monitoring. Vibration of the power transmission GIL pipeline is a key monitoring focus; when the pipeline vibration intensity or frequency is excessive, the pipeline is considered to be in poor operating condition.

[0003] In the existing technology, a large number of point vibration sensors are installed on the shell of the power transmission GIL pipeline to monitor the vibration at different locations of the pipeline. This not only fails to monitor the pipeline vibration in all aspects, but also makes the operation and maintenance of the entire monitoring system very complicated due to the large number of devices. In addition, a large number of sensors will also affect the structure of the power transmission GIL pipeline itself. Summary of the Invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, this application aims to provide a vibration detection method and system for power transmission GIL pipelines.

[0005] In a first aspect, the present invention proposes a vibration detection method for a power transmission GIL pipeline, wherein a sensing optical cable is laid on the outside of the power transmission GIL pipeline, and the sensing optical cable contains an optical fiber. The method includes the following steps: After sending a laser beam into the optical fiber, the reflected light signal is received from within the optical fiber. The light signal is used to characterize the change in the luminous intensity of the sensing optical cable along the length of the pipe. The optical signal is converted into an electrical digital signal corresponding to the luminous intensity; The electrical digital signal is calculated to obtain the vibration intensity at multiple locations along the length of the pipeline; When the vibration intensity is determined to be greater than or equal to a first preset threshold, an alarm indication is issued. The alarm indication includes at least the numerical value of the vibration intensity and the location corresponding to the vibration intensity.

[0006] According to the technical solution provided in the embodiments of this application, calculating the electrical digital signal to obtain the vibration intensity at multiple locations along the length of the pipeline includes at least the following steps: The electrical digital signal is processed to obtain the pipe vibration data per second; The vibration data per second are demodulated using a moving average difference algorithm and a fast Fourier transform algorithm to obtain the vibration intensity at multiple locations along the length of the pipe.

[0007] According to the technical solution provided in the embodiments of this application, after demodulating the vibration data per second using the moving average difference algorithm and the fast Fourier transform algorithm, the vibration frequencies at multiple positions along the length of the pipe are obtained. The vibration frequencies are used to verify the accuracy of the obtained vibration intensity.

[0008] According to the technical solution provided in the embodiments of this application, after obtaining the vibration intensity and before determining that the vibration intensity is greater than or equal to a first preset threshold, the following steps are further included: Based on the vibration frequencies, plot the vibration frequency variation curve of the pipeline; Based on the vibration intensities described above, plot the vibration intensity variation curve of the pipeline; When it is determined that the change trends of the vibration frequency change curve and the vibration intensity change curve are the same at each of the specified positions, the vibration intensity is compared with the first preset threshold.

[0009] According to the technical solution provided in the embodiments of this application, after obtaining the vibration intensity at multiple locations along the length of the pipeline, the following steps are further included: When the vibration intensity is determined to be greater than or equal to a second preset threshold, an early warning instruction is issued. The early warning instruction includes at least the numerical value of the vibration intensity and the location corresponding to the vibration intensity. The second preset threshold is less than the first preset threshold.

[0010] Secondly, the present invention proposes a vibration detection system for power transmission GIL pipelines, used to perform the vibration detection method for power transmission GIL pipelines described above, the system comprising: The sensing module includes a sensing optical cable laid outside the power transmission GIL pipeline. After a laser is sent to the optical fiber of the sensing optical cable, the sensing module is configured to receive the light signal reflected back from the optical fiber. The light signal is used to characterize the change in the light emission intensity of the sensing optical cable along the length direction of the pipeline. The calculation module is configured to perform photoelectric conversion on the optical signal to obtain an electrical digital signal corresponding to the luminous intensity, and to calculate the electrical digital signal to obtain the vibration intensity at multiple positions along the length of the pipe. The control module is configured to issue an alarm indication when the vibration intensity is greater than or equal to a first preset threshold. The alarm indication includes at least the value of the vibration intensity and the location corresponding to the vibration intensity.

[0011] According to the technical solution provided in the embodiments of this application, the calculation module includes at least a data demodulation unit and a data calculation unit. The data demodulation unit is connected to the sensing optical cable. The data demodulation unit is configured to perform photoelectric conversion on the optical signal to obtain an electrical digital signal corresponding to the luminous intensity. The data calculation unit is configured to calculate the electrical digital signal to obtain pipeline vibration data per second.

[0012] According to the technical solution provided in the embodiments of this application, the control module includes at least a judgment unit and a monitoring unit. The judgment unit is configured to judge the magnitude of the vibration intensity and the first preset threshold. The monitoring unit is configured to display the vibration intensity at each location of the pipeline and issue the alarm indication when the vibration intensity is greater than or equal to the first preset threshold.

[0013] According to the technical solution provided in the embodiments of this application, the data demodulation unit has a signal transmission channel, and an optical cable connection box is provided between the sensing optical cable and the data demodulation unit. The optical cable connection box is used to connect the sensing optical cable and the signal transmission channel.

[0014] According to the technical solution provided in the embodiments of this application, the power transmission GIL pipeline is provided with an optical cable fixing component, which is used to fix the sensing optical cable.

[0015] In summary, this application proposes a vibration detection method and system for a power transmission GIL pipeline. The power transmission GIL pipeline is externally covered with a sensing optical cable containing an optical fiber. The method includes sending a laser to the optical fiber, receiving the reflected light signal from within the optical fiber, the light signal being used to characterize the change in the light emission intensity of the sensing optical cable along the length of the pipeline, photoelectric conversion of the light signal to obtain an electrical digital signal corresponding to the light emission intensity, calculating the electrical digital signal to obtain the vibration intensity at multiple locations along the length of the pipeline, and issuing an alarm indication when the vibration intensity is greater than or equal to a first preset threshold. The alarm indication includes at least the numerical value of the vibration intensity and the location corresponding to the vibration intensity.

[0016] This method involves laying a sensing optical cable outside the power transmission GIL pipeline. The light signal returned by the optical fiber in the sensing optical cable reflects the change in light intensity. Since the change in light intensity is caused by the vibration of the power transmission GIL pipeline, the vibration information of the power transmission GIL pipeline can be calculated by the change in light intensity. The vibration information can then be used to further determine whether there is any vibration anomaly. This not only enables comprehensive monitoring of pipeline vibration, but also simplifies the operation and maintenance process, and does not affect the structure of the power transmission GIL pipeline itself. Attached Figure Description

[0017] Figure 1A flowchart illustrating the steps of a vibration detection method for a power transmission GIL pipeline provided in an embodiment of this application; Figure 2 This is a connection diagram of the vibration detection system for the power transmission GIL pipeline provided in an embodiment of this application. Detailed Implementation

[0018] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0019] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0020] Example 1 As mentioned in the background section, this application proposes a vibration detection method for power transmission GIL pipelines to address the problems in the prior art. The power transmission GIL pipeline is externally covered with a sensing optical cable, which contains optical fibers. Please refer to [reference needed]. Figure 1 As shown, the method includes the following steps: S1. After sending a laser to the optical fiber, receive the light signal reflected back from the optical fiber. The light signal is used to characterize the change in the light emission intensity of the sensing optical cable along the length of the pipe. S2. The optical signal is photoelectrically converted to obtain an electrical digital signal corresponding to the luminous intensity; S3. Solve the electrical digital signal to obtain the vibration intensity at multiple locations along the length of the pipeline; S4. When it is determined that the vibration intensity is greater than or equal to a first preset threshold, an alarm indication is issued. The alarm indication includes at least the value of the vibration intensity and the location corresponding to the vibration intensity.

[0021] The working principle of this method is as follows: the vibration of the power transmission GIL pipeline will cause changes in the optical signal, that is, the change in the light intensity can characterize the vibration change of the power transmission GIL pipeline. Therefore, this invention uses the optical signal reflected back from the optical fiber in the optical sensing cable to perform signal conversion, convert the analog signal into a digital signal, and perform data processing to obtain the vibration intensity at multiple positions along the length of the pipeline.

[0022] This method measures pipes with a length greater than or equal to 40km. Optical fibers are distributed along the pipes for vibration detection, enabling real-time, online, and continuous vibration signal measurement. It is a detection method that integrates optics, electricity, signal detection, and computer technology, and has advantages such as real-time monitoring, multi-dimensional data demodulation, graphical intelligent analysis, long measurement distance, precise positioning, intrinsic safety, and immunity to electromagnetic interference.

[0023] In a preferred embodiment, calculating the electrical digital signal to obtain the vibration intensity at multiple locations along the length of the pipe includes at least the following steps: The electrical digital signal is processed to obtain the pipe vibration data per second; The vibration data per second are demodulated using a moving average difference algorithm and a fast Fourier transform algorithm to obtain the vibration intensity at multiple locations along the length of the pipe.

[0024] In a preferred embodiment, after demodulating the vibration data per second using a moving average difference algorithm and a fast Fourier transform algorithm, vibration frequencies at multiple locations along the length of the pipe are obtained. These vibration frequencies are used to verify the accuracy of the obtained vibration intensity.

[0025] Specifically, the calculation is performed based on the Φ-OTDR principle, and then the moving average difference algorithm and the fast Fourier transform algorithm are used for demodulation to obtain the vibration information such as vibration intensity and vibration frequency at multiple positions along the length of the pipeline.

[0026] Specifically, after processing the vibration data at different locations measured in real time using the Fast Fourier Transform algorithm, the vibration frequency of the pipeline can be analyzed. The domestic AC power transmission frequency is mainly 50Hz. The system can monitor that the vibration frequency of the GIL pipeline is 50Hz when it is working normally. When the calculated vibration frequency is greater than 50Hz, it indicates that the pipeline is not in good operating condition and the vibration intensity is large. The vibration frequency can further help verify whether the obtained vibration intensity is correct.

[0027] In a preferred embodiment, after obtaining the vibration intensity but before determining that the vibration intensity is greater than or equal to a first preset threshold, the following steps are further included: Based on the vibration frequencies, plot the vibration frequency variation curve of the pipeline; Based on the vibration intensities described above, plot the vibration intensity variation curve of the pipeline; When it is determined that the change trends of the vibration frequency change curve and the vibration intensity change curve are the same at each of the specified positions, the vibration intensity is compared with the first preset threshold.

[0028] Specifically, the trend of change is the trend of change between the current position and the previous position. When the trends of change of the vibration frequency and the vibration intensity are the same at the current position, the vibration intensity obtained at the current position is considered reliable. At this time, the vibration intensity is compared with the first preset threshold to make a relevant judgment, which can improve the accuracy of the judgment.

[0029] In a preferred embodiment, after obtaining the vibration intensity at multiple locations along the length of the pipe, the method further includes the following step: When the vibration intensity is determined to be greater than or equal to a second preset threshold, an early warning instruction is issued. The early warning instruction includes at least the numerical value of the vibration intensity and the location corresponding to the vibration intensity. The second preset threshold is less than the first preset threshold.

[0030] Specifically, when the vibration intensity is equal to the first preset threshold, the pipeline vibration will seriously affect the pipeline's power transmission capacity. Therefore, when the vibration intensity is greater than or equal to the first preset threshold, an alarm needs to be triggered in time for fault location and repair to ensure the stability of the pipeline's power transmission. When the vibration intensity is equal to the second preset threshold, the pipeline vibration does not affect the current power transmission capacity of the pipeline. However, as power transmission continues, the vibration intensity may accumulate to an excessive level in the future, reaching the first preset threshold. Therefore, when the vibration intensity is greater than or equal to the second preset threshold, an early warning instruction is issued to avoid problems in time and prevent them from happening in the first place.

[0031] Secondly, this invention proposes a vibration detection system for power transmission GIL pipelines, used to perform the vibration detection method for power transmission GIL pipelines described above. Please refer to [reference needed]. Figure 2 As shown, the system includes: The sensing module includes a sensing optical cable laid outside the power transmission GIL pipeline. After a laser is sent to the optical fiber of the sensing optical cable, the sensing module is configured to receive the light signal reflected back from the optical fiber. The light signal is used to characterize the change in the light emission intensity of the sensing optical cable along the length direction of the pipeline. The calculation module is configured to perform photoelectric conversion on the optical signal to obtain an electrical digital signal corresponding to the luminous intensity, and to calculate the electrical digital signal to obtain the vibration intensity at multiple positions along the length of the pipe. The control module is configured to issue an alarm indication when the vibration intensity is greater than or equal to a first preset threshold. The alarm indication includes at least the value of the vibration intensity and the location corresponding to the vibration intensity.

[0032] This system is used to complete the vibration detection method for the aforementioned power transmission GIL pipeline. Since the optical fiber is both a sensor and a transmission unit, the system can achieve long-distance full-range vibration detection using only one optical fiber, and the installation and maintenance are simple and safe.

[0033] In a preferred embodiment, the calculation module includes at least a data demodulation unit and a data calculation unit. The data demodulation unit is connected to the sensing optical cable. The data demodulation unit is configured to perform photoelectric conversion on the optical signal to obtain an electrical digital signal corresponding to the luminous intensity. The data calculation unit is configured to calculate the electrical digital signal to obtain pipeline vibration data per second.

[0034] In a preferred embodiment, the control module includes at least a judgment unit and a monitoring unit. The judgment unit is configured to judge the magnitude of the vibration intensity and the first preset threshold. The monitoring unit is configured to display the vibration intensity at each location of the pipeline and issue the alarm indication when the vibration intensity is greater than or equal to the first preset threshold.

[0035] In a preferred embodiment, the data demodulation unit has a signal transmission channel, and an optical cable connector box is provided between the sensing optical cable and the data demodulation unit. The optical cable connector box is used to connect the sensing optical cable and the signal transmission channel.

[0036] In a preferred embodiment, an optical cable fixing component is provided outside the power transmission GIL pipeline, and the optical cable fixing component is used to fix the sensing optical cable.

[0037] Specifically, the calculation module can be a vibration detection host, and the control module of the vibration detection host can be an intelligent monitoring and management platform. The vibration detection host can be placed in the control room. The sensing optical cable and the vibration detection host are connected through the transmission optical cable. The sensing optical cable enters the working area of ​​the power transmission GIL pipeline by means of internal or external laying. In this working area, the optical cable fixing component is fixed to the pipeline. The optical cable fixing component can be an optical cable fixator. Several optical cable fixators can be set in the length direction of the pipeline to ensure that the sensing optical cable is completely covered on the pipeline.

[0038] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this invention, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. A vibration detection method for a power transmission GIL pipeline, wherein a sensing optical cable is laid outside the power transmission GIL pipeline, and the sensing optical cable contains an optical fiber, characterized in that, Includes the following steps: After sending a laser beam into the optical fiber, the reflected light signal is received from within the optical fiber. The light signal is used to characterize the change in the luminous intensity of the sensing optical cable along the length of the pipe. The optical signal is converted into an electrical digital signal corresponding to the luminous intensity; The electrical digital signal is calculated to obtain the vibration intensity at multiple locations along the length of the pipeline; When the vibration intensity is determined to be greater than or equal to a first preset threshold, an alarm indication is issued. The alarm indication includes at least the value of the vibration intensity and the location corresponding to the vibration intensity. Decoding the electrical digital signal to obtain the vibration intensity at multiple locations along the length of the pipe includes at least the following steps: The electrical digital signal is processed to obtain the pipe vibration data per second; The vibration data per second are demodulated using a moving average difference algorithm and a fast Fourier transform algorithm to obtain the vibration intensity at multiple locations along the length of the pipe. After demodulating the vibration data per second using the moving average difference algorithm and the fast Fourier transform algorithm, the vibration frequencies at multiple locations along the length of the pipe are obtained. These vibration frequencies are used to verify the accuracy of the obtained vibration intensity. After obtaining the vibration intensity, and before determining that the vibration intensity is greater than or equal to a first preset threshold, the following steps are also included: Based on the vibration frequencies, plot the vibration frequency variation curve of the pipeline; Based on the vibration intensities described above, plot the vibration intensity variation curve of the pipeline; When it is determined that the change trends of the vibration frequency change curve and the vibration intensity change curve are the same at each of the specified positions, the vibration intensity is compared with the first preset threshold.

2. The vibration detection method for power transmission GIL pipelines according to claim 1, characterized in that: After obtaining the vibration intensity at multiple locations along the length of the pipe, the following steps are also included: When the vibration intensity is determined to be greater than or equal to a second preset threshold, an early warning instruction is issued. The early warning instruction includes at least the numerical value of the vibration intensity and the location corresponding to the vibration intensity. The second preset threshold is less than the first preset threshold.

3. A vibration detection system for a power transmission GIL pipeline, characterized in that: The system for performing the vibration detection method for a power transmission GIL pipeline as described in any one of claims 1-2 includes: The sensing module includes a sensing optical cable laid outside the power transmission GIL pipeline. After a laser is sent to the optical fiber of the sensing optical cable, the sensing module is configured to receive the light signal reflected back from the optical fiber. The light signal is used to characterize the change in the light emission intensity of the sensing optical cable along the length direction of the pipeline. The calculation module is configured to perform photoelectric conversion on the optical signal to obtain an electrical digital signal corresponding to the luminous intensity, and to calculate the electrical digital signal to obtain the vibration intensity at multiple positions along the length of the pipe. The control module is configured to issue an alarm indication when the vibration intensity is greater than or equal to a first preset threshold. The alarm indication includes at least the value of the vibration intensity and the location corresponding to the vibration intensity.

4. The vibration detection system for a power transmission GIL pipeline according to claim 3, characterized in that: The calculation module includes at least a data demodulation unit and a data calculation unit. The data demodulation unit is connected to the sensing optical cable. The data demodulation unit is configured to perform photoelectric conversion on the optical signal to obtain an electrical digital signal corresponding to the luminous intensity. The data calculation unit is configured to calculate the electrical digital signal to obtain pipeline vibration data per second.

5. The vibration detection system for a power transmission GIL pipeline according to claim 4, characterized in that: The control module includes at least a judgment unit and a monitoring unit. The judgment unit is configured to judge the magnitude of the vibration intensity and the first preset threshold. The monitoring unit is configured to display the vibration intensity at each location of the pipeline and issue the alarm indication when the vibration intensity is greater than or equal to the first preset threshold.

6. The vibration detection system for a power transmission GIL pipeline according to claim 5, characterized in that: The data demodulation unit has a signal transmission channel, and an optical cable connector box is provided between the sensing optical cable and the data demodulation unit. The optical cable connector box is used to connect the sensing optical cable and the signal transmission channel.

7. The vibration detection system for power transmission GIL pipelines according to claim 3, characterized in that: The power transmission GIL pipeline is equipped with an optical cable fixing component, which is used to fix the sensing optical cable.

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