A GIS endoscopic temperature measurement system based on fiber optic image bundle

Abstract

This invention discloses a GIS endoscopic temperature measurement system based on fiber optic image bundles, comprising an infrared signal sensing and transmission module and a data processing and detection module. The infrared signal sensing and transmission module includes a front-end optical path and an image acquisition device. The data processing and detection module includes a host computer, which includes a data storage module, an information display module, a holographic temperature field analysis module, a temperature early warning module, and a remote control module. The image acquisition device includes an image sensor and a lower-level PCB circuit board. This invention enables direct infrared image observation by embedding the front-end optical path within the GIS tank. The observation range is adjusted using lens combinations. A fiber optic bundle is added between the front-end optical path and the image acquisition device to achieve photoelectric signal separation. Finally, the host computer completes temperature signal analysis and network transmission, overcoming the shortcomings of existing monitoring technologies that are not direct, timely, comprehensive, or accurate enough.

Description

Technical Field

[0001] This invention belongs to the field of GIS monitoring equipment technology, specifically relating to a GIS endoscopic temperature measurement system based on an optical fiber image transmission bundle. Background Technology

[0002] In power systems, GIS (Gas Insulated Switchgear) is widely used due to its compact structure and reliable performance. However, as GIS equipment ages, factors such as wear, surface corrosion, and loosening of pre-tightening forces in the internal electrical connections deteriorate the electrical contact morphology, leading to localized overheating and ultimately equipment failure. Therefore, implementing online temperature monitoring of GIS equipment to detect and eliminate potential thermal failures in advance is of paramount importance for the safe and reliable operation of GIS systems.

[0003] Current methods for monitoring the internal temperature field of GIS can be mainly divided into three categories: The first category involves external fixed-point temperature measurement to infer and determine the internal overheating anomalies of the GIS. Under this method, due to the numerous factors causing abnormal heating in the GIS, the uncertain location of hotspots, and the significant time delay required for the heat flow from the internal overheating source to the shell to reach equilibrium, the monitoring results are difficult to guarantee in terms of accuracy, speed, and precision. The second category involves placing temperature sensors inside the GIS to achieve fixed-point temperature measurement. This technical method reacts promptly to overheating at the measurement point, but if the abnormally hot spot is not at the measurement point, it will lead to deviations in the measurement results. In addition, since this measurement is essentially a contact measurement, it may also affect related components within the GIS. The third type is industrial-grade infrared thermal imagers. Although this device can detect the temperature field through the observation hole of the primary equipment, the reserved observation hole is usually for visual inspection, the location is limited, and it often does not target the critical heat-generating parts. Moreover, industrial-grade infrared thermal imaging equipment is bulky, and window installation will seriously affect the mechanical strength and airtightness of the casing. In addition, industrial products do not effectively separate the optical path and the circuit in their structure, which will also introduce insulation hazards. More importantly, the working wavelength of industrial-grade thermal imagers is not customized for GIS. Direct application often results in a measurement range that is too small, high-temperature points are saturated and cannot be quantified, or high-temperature points can be measured, but the resolution in low-temperature areas is extremely low. Summary of the Invention

[0004] The purpose of this invention is to provide a GIS endoscopic temperature measurement system based on fiber optic image bundles. This system allows for direct infrared image observation by embedding the front-end optical path within the GIS tank. The observation range is adjusted using lens combinations. An optical fiber bundle is added between the front-end optical path and the image acquisition unit to achieve photoelectric signal separation. Finally, a host computer is used to complete temperature signal analysis and network transmission. This overcomes the shortcomings of existing monitoring technologies, such as being insufficiently direct, timely, comprehensive, and accurate, thereby solving the problems mentioned in the background section of the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] An endoscopic temperature measurement system for GIS based on fiber optic image bundles includes an infrared signal sensing and transmission module that acquires infrared images of the internal temperature field of a GIS and converts them into electrical signals, and a data processing and detection module that performs holographic temperature field data analysis and temperature early warning based on infrared thermal images. The infrared signal sensing and transmission module includes a front-end optical path and an image acquisition device. The front-end optical path is connected to the image acquisition device through an infrared fiber bundle. The data processing and detection module includes a host computer. The image acquisition device is communicatively connected to the host computer through a signal transmission cable. The host computer includes a data storage module, an information display module, a holographic temperature field analysis module, a temperature early warning module, and a remote control module. The image acquisition device includes an image sensor and a lower-level PCB circuit board. The image sensor is mounted on the lower-level PCB circuit board, and the front-end optical path is connected to the lower-level PCB circuit board through an infrared fiber bundle.

[0007] Preferably, the front-end optical path includes multiple lens groups, flanges, and SF6 leak-proof gaskets. In use, mounting holes are made on the outer wall of the GIS tank, and the front-end optical path is sealed and installed in the mounting holes with sealant to monitor the internal temperature of the GIS tank. The parameters of the lens groups are calculated according to the specific application scenario.

[0008] Preferably, the front-end optical path serves two purposes: first, to image the internal temperature field of the GIS and then accurately transmit the collected infrared signals to the optical fiber bundle; second, to seal the installation holes of the GIS tank to prevent SF6 leakage.

[0009] Preferably, the infrared fiber bundle includes a pigtail, a fiber core, a fiber core cladding, a sheath, and a beam expander; the infrared fiber bundle is a flexible structure; the pigtail of the infrared fiber bundle is detachably connected to the flange of the front-end optical path, and the pigtail is connected to the lens group of the front-end optical path; wherein, the infrared fiber material, drawing process, fiber arrangement technology, end face treatment, and optical path design are specifically studied according to the application scenario.

[0010] Preferably, the image acquisition device further includes a housing, and the housing and the expander of the infrared fiber bundle are detachably connected. The housing has a signal transmission and power supply cable interface. The image sensor converts the received infrared light wave signal into an electrical signal, which is then sent to the host computer for data analysis to achieve human-computer interaction. The lower-level PCB board controls the image sensor, performs preliminary calibration of the electrical signal, and transmits the signal.

[0011] Preferably, the holographic temperature field analysis module includes analysis functions such as data calibration and compensation, temperature range, average temperature, temperature gradient, and temperature time-varying characteristics; wherein, the temperature early warning module includes a comprehensive evaluation of holographic temperature information and a warning module for abnormal temperature rise locations.

[0012] Preferably, in order to restore the true signal, the holographic temperature field analysis module should first perform parameter calibration of the acquisition equipment and infrared image data compensation, due to the different infrared emissivity of different material surfaces inside the GIS, the selective absorption of infrared wavelengths of SF6 at 10.6μm, the inability of the beam structure of each optical unit to be fully coupled, and the influence of inherent factors of each unit on thermal radiation loss. Based on obtaining accurate data, holographic temperature field analysis should be performed on the temperature field characteristics of the GIS, including temperature range, average temperature, temperature gradient, and temperature time-varying characteristics.

[0013] Preferably, to ensure the safe and stable operation of the equipment and the life and health safety of maintenance personnel, the temperature early warning module, after comprehensive evaluation based on holographic temperature field parameters, issues an integrated audio-visual warning at the location of abnormal temperature rise, prompting staff to handle the situation promptly; the remote control module can support online monitoring of the internal temperature field of GIS, remote control of monitoring equipment, and large-scale cloud data storage.

[0014] Technical effects and advantages of the present invention: The GIS endoscopic temperature measurement system based on fiber optic image bundle proposed in this invention has the following advantages compared with the prior art:

[0015] This invention enables direct infrared image observation by embedding the front-end optical path of the device within the GIS tank. The observation range is adjusted by lens combination, and an optical fiber bundle is added between the front-end optical path and the image acquisition device to achieve photoelectric signal separation. Finally, the host computer is used to complete temperature signal analysis and network transmission, overcoming the shortcomings of existing monitoring technologies that are not direct, timely, comprehensive, or accurate enough. Attached Figure Description

[0016] Figure 1 This is a system block diagram of the present invention;

[0017] Figure 2 This is a schematic diagram of the process of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The specific embodiments described herein are merely used to explain the present invention and are not intended to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] This invention provides, for example Figure 1-2The illustrated GIS endoscopic temperature measurement system based on fiber optic image bundle includes an infrared signal sensing and transmission module that acquires infrared images of the internal temperature field of the GIS and converts them into electrical signals, and a data processing and detection module that performs holographic temperature field data analysis and temperature early warning based on the infrared thermal image. The infrared signal sensing and transmission module includes a front-end optical path and an image acquisition device. The front-end optical path is connected to the image acquisition device through an infrared fiber bundle. The data processing and detection module includes a host computer. The image acquisition device is connected to the host computer via a signal transmission cable. The host computer includes a data storage module, an information display module, a holographic temperature field analysis module, a temperature early warning module, and a remote control module. The image acquisition device includes an image sensor and a lower-level PCB circuit board. The image sensor is mounted on the lower-level PCB circuit board, and the front-end optical path is connected to the lower-level PCB circuit board through an infrared fiber bundle.

[0020] The front-end optical path includes multiple lens groups, flanges, and SF6 leak-proof gaskets. In use, mounting holes are made on the outer wall of the GIS tank, and the front-end optical path is sealed in the mounting holes with sealant to monitor the internal temperature of the GIS tank. The parameters of the lens groups are calculated according to the specific application scenario.

[0021] The front-end optical path serves two purposes: first, to image the internal temperature field of the GIS and then accurately transmit the collected infrared signals to the optical fiber bundle; second, to seal the installation holes of the GIS tank to prevent SF6 leakage.

[0022] The infrared fiber bundle includes a pigtail, a fiber core, a core cladding, a sheath, and a beam expander; the infrared fiber bundle is a flexible structure; the pigtail of the infrared fiber bundle is detachably connected to the flange of the front-end optical path, and the pigtail is connected to the lens group of the front-end optical path; the infrared fiber material, drawing process, fiber arrangement technology, end face treatment, and optical path design are specifically studied according to the application scenario.

[0023] The image acquisition unit also includes a housing, and the housing and the expander of the infrared fiber bundle are detachably connected. The housing has a signal transmission and power supply cable interface. The image sensor converts the received infrared light wave signal into an electrical signal, which is then sent to the host computer for data analysis to realize human-computer interaction. The lower-level PCB board controls the image sensor, performs preliminary calibration of the electrical signal, and transmits the signal.

[0024] The holographic temperature field analysis module includes analysis functions such as data calibration and compensation, temperature range, average temperature, temperature gradient, and temperature time-varying characteristics; among them, the temperature early warning module includes a comprehensive evaluation of holographic temperature information and a warning module for abnormal temperature rise locations.

[0025] To reproduce the true signal, the holographic temperature field analysis module should first calibrate the acquisition equipment parameters and compensate for the infrared image data, due to the different infrared emissivity of different materials on the surface inside the GIS, the selective absorption of infrared wavelengths of SF6 at 10.6μm, the incomplete coupling of the beam structures of each optical unit, and the inherent factors of each unit affecting thermal radiation loss. Based on the accurate data obtained, the holographic temperature field analysis should be performed on the temperature field characteristics of the GIS, including the internal temperature range, average temperature, temperature gradient, and temperature time-varying characteristics.

[0026] To ensure the safe and stable operation of equipment and the health and safety of maintenance personnel, the temperature early warning module, based on a comprehensive evaluation of holographic temperature field parameters, issues an integrated audio-visual warning at locations of abnormal temperature rises, prompting staff to take timely action; the remote control module supports online monitoring of the internal temperature field of GIS, remote control of monitoring equipment, and large-scale cloud data storage.

[0027] This invention significantly reduces the risk of SF6 leakage after installation by employing a micro-diameter tubular sealed front-end optical path and sealing adhesive. The front-end optical path is embedded in the GIS tank for direct acquisition of image information, and works with a host computer to achieve holographic analysis of the temperature field at the observation point, accurately grasping the dynamic information of the temperature field under the high-pressure SF6 atmosphere inside the GIS. Flexible optical fiber bundles are used to separate optical and electrical signals, ensuring that the insulation strength of the GIS equipment is not affected, guaranteeing that the electrical signal of the image acquisition unit is not distorted by the electromagnetic field of the GIS, and overcoming the limitations of the test location. The combined optical structure design makes the equipment easy to install, convenient to replace, and has a small storage volume, effectively ensuring that the detection equipment matches the life cycle of the GIS. In the future, it can be extended to ultraviolet band measurement by matching different wavelengths.

[0028] The infrared signal sensing and transmission module includes a front-end optical path embedded in the GIS equipment mounting hole and an image acquisition device connected to the front-end optical path via an infrared fiber bundle. The data processing and monitoring module includes a host computer connected to the image acquisition device via a signal transmission cable. In use, the hardware module acquires thermal images of the GIS interior, completing non-contact temperature field measurement. The host computer software then accurately quantifies multi-dimensional temperature information based on the infrared thermal images, enabling real-time monitoring of the temperature field and timely and accurate early warning of abnormal temperature rises within the high-pressure SF6 atmosphere environment inside the GIS.

[0029] To achieve a large observation range within the confined space of the GIS and ensure the front-end optical path signal enters the fiber bundle at the optimal incident angle, the front-end optical path is designed with multiple lens combinations. The specific matching parameters of the lens groups should be flexibly and accurately calculated based on the GIS equipment being inspected. Since the lens groups are located within a micro-diameter tubular sealing layer with low tolerance for error, precision optical processing equipment should be used for lens fabrication. Considering the special gas environment of GIS and the high light power density generated by the electric arc, the lenses should be made of corrosion-resistant materials with a high light transmission damage threshold. The front-end optical path is installed inside the mounting hole on the GIS tank via a flange, with SF6 leak-proof gaskets installed at the connection points. All gaps in the front-end optical path are filled with anti-corrosion sealant.

[0030] Unlike conventional atmospheric environments, GIS operates under high voltage and high current, and is filled with 0.6MPa high-pressure SF6 gas. If the GIS tank leaks or depressurizes, or if debris inside causes partial discharge leading to GIS shutdown, it will severely impact the safe and stable operation of the power system. To meet the sealing and pressure resistance requirements of GIS, the tank must be intact and free of cracks. For pre-manufactured GIS, micro-diameter mounting holes are machined using debris-free and non-destructive processes, such as femtosecond laser cold processing. For unmanufactured GIS, the tank, mounting holes, and static flanges are designed as a single unit during manufacturing. The location of the mounting holes should be selected based on the observation requirements, choosing the optimal observation point for the target temperature field.

[0031] Electromagnetic interference from GIS can cause distortion of the electrical signals of image sensors, and the design of fixing sensors to GIS also limits the testing range for operators. Therefore, the flexible optical fiber between the front-end optical path and the image acquisition unit isolates the electromagnetic signals of the GIS main equipment from the electrical signals of the image acquisition unit's PCB circuit, achieving separation of optical and electrical signals and ensuring that the PCB acquires the true signal. Another function is that the addition of the fiber bundle overcomes the limitations of the testing location, enabling the integration of on-site testing and remote monitoring.

[0032] Because the fiber core is relatively brittle and can be bent to a certain extent, it is easy to break if the curvature is too large. Therefore, the fiber core cladding and protective layer will play a role in protecting the fiber core. In order to ensure that each optical unit is precisely matched and to suppress light transmission loss, pigtails and expanders are installed at both ends of the fiber bundle to ensure the precision of the equipment.

[0033] Due to the gaps between the fiber cores, a microlens is added to one end of the pigtail to ensure that the image sensor receives a complete infrared image; the material, drawing process, fiber arrangement technology, end face treatment, and optical path design of the fiber bundle are specifically studied according to the application scenario.

[0034] To minimize the equipment's footprint and facilitate easy replacement, the enclosure and beam expander are detachably connected; the enclosure has signal transmission and power supply cable interfaces.

[0035] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A GIS endoscopic temperature measurement system based on fiber optic image transmission bundle, comprising an infrared signal sensing and transmission module for acquiring infrared images of the internal temperature field of the GIS and converting them into electrical signals, and a data processing and detection module for performing holographic temperature field data analysis, i.e., temperature early warning, based on the infrared thermal image, characterized in that: The infrared signal sensing and transmission module includes a front-end optical path and an image acquisition device. The front-end optical path is connected to the image acquisition device through an infrared fiber bundle. The data processing and detection module includes a host computer. The image acquisition device is communicatively connected to the host computer through a signal transmission cable. The host computer includes a data storage module, an information display module, a holographic temperature field analysis module, a temperature early warning module, and a remote control module. The image acquisition device includes an image sensor and a lower-level PCB circuit board. The image sensor is mounted on the lower-level PCB circuit board, and the front-end optical path is connected to the lower-level PCB circuit board through an infrared fiber bundle. The front-end optical path includes multiple lens groups, flanges, and SF6 leak-proof gaskets. In use, mounting holes are made on the outer wall of the GIS tank, and the front-end optical path is sealed and installed in the mounting holes with sealant to monitor the internal temperature of the GIS tank. The parameters of the lens groups are calculated according to the specific application scenario. The front-end optical path serves two purposes: first, to image the internal temperature field of the GIS and then accurately transmit the collected infrared signals to the optical fiber bundle; second, to seal the installation holes of the GIS tank to prevent SF6 leakage. The image acquisition device also includes a housing, and the housing and the expander of the infrared fiber bundle are detachably connected. The housing has a signal transmission and power supply cable interface. The infrared fiber bundle includes a pigtail, a fiber core, a fiber core cladding, a protective layer, and a beam expander; the infrared fiber bundle is a flexible structure; the pigtail of the infrared fiber bundle is detachably connected to the flange of the front-end optical path, and the pigtail is connected to the lens group of the front-end optical path. The function of the image sensor is to convert the received infrared light wave signal into an electrical signal, which is then sent to the host computer for data analysis to realize human-computer interaction; the lower-level computer PCB board is responsible for controlling the image sensor, initially calibrating the electrical signal, and transmitting the signal. The holographic temperature field analysis module includes functions for data calibration and compensation, temperature range, average temperature, temperature gradient and time-varying temperature characteristics analysis; the temperature early warning module includes a comprehensive evaluation of holographic temperature information and a warning module for abnormal temperature rise locations. The temperature early warning module, after comprehensive evaluation based on holographic temperature field parameters, issues an integrated audio-visual warning at the location of abnormal temperature rise, prompting staff to take timely action; the remote control module can support online monitoring of the internal temperature field of GIS, remote control of monitoring equipment, and large-scale cloud data storage.

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