GIS bus contact temperature rise detection method and device

Abstract

According to the GIS bus contact temperature rise detection method and device, ultrasonic waves are transmitted and received through an ultrasonic transducer, the signal transit time is measured, the propagation speed is calculated, and then the temperature is calculated according to the relation between the speed and the temperature. And calculating the optimized frequency by considering the thermal interference of the temperature on the frequency, comparing the optimized frequency with a preset range, and adjusting the emission frequency until the emission frequency reaches the standard. According to the method, non-contact real-time accurate temperature measurement is realized, and the operation safety and reliability of GIS equipment are improved.

Description

Technical Field

[0001] The present application belongs to the field of GIS busbar contact temperature measurement, and in particular, relates to a GIS busbar contact temperature rise detection method and device. Background Art

[0002] In the power system, GIS (gas insulated switchgear) is an important equipment for high-voltage power transmission and distribution, and its operating stability and safety are of vital importance. As a key component, GIS busbar contacts are responsible for the transmission and distribution of current. During operation, they will generate heat due to the passage of current, resulting in temperature rise. If the contact temperature is too high, it may cause serious consequences such as aging of insulation materials, damage to equipment, and even fire.

[0003] Traditional GIS busbar contact temperature detection methods mainly rely on contact temperature sensors, such as thermocouples or thermal resistors. However, these contact sensors have problems such as complex installation, easy damage, slow response speed, and possible impact on electrical performance. In addition, in the closed environment of GIS, the installation and maintenance of contact sensors are relatively difficult, and it is difficult to accurately monitor the temperature changes on the contact surface in real time. Summary of the invention

[0004] The purpose of the present application is to overcome the defects in the above-mentioned prior art and to provide a method and device for detecting the temperature rise of GIS busbar contacts.

[0005] The present application provides a GIS busbar contact temperature rise detection method, comprising:

[0006] S1 installs an ultrasonic transducer on both sides of the GIS busbar contact as the transmitting and receiving ends of the ultrasonic wave;

[0007] S2 starts the transmitting end to transmit an ultrasonic signal according to a preset transmitting frequency;

[0008] S3: measuring the transit time of the ultrasonic signal from the transmitting end to the receiving end through the receiving end;

[0009] S4 calculates the propagation speed of the ultrasonic signal in the GIS bus contact based on the transit time;

[0010] S5, calculating the temperature value of the GIS bus contact according to the first correlation between the propagation speed and the temperature on the GIS bus contact;

[0011] S6, calculating the optimized frequency according to the second correlation between the temperature value and the thermal interference effect of the ultrasonic frequency;

[0012] S7 determines whether the difference between the optimized frequency and the transmitting frequency is within a preset range;

[0013] S8: if the difference is not within the preset range, setting the optimized frequency as a new transmission frequency, and repeating steps S2 to S8;

[0014] S9: if the difference is within the preset range, output the temperature value as a temperature measurement value.

[0015] Optionally, before step S1, the method further includes:

[0016] The positions for installing ultrasonic transducers on both sides of the GIS busbar contact are determined according to the heat flow path after the GIS busbar contact is abnormally heated.

[0017] Optionally, in step S2, the preset transmission frequency is adjustable.

[0018] Optionally, step S4 includes:

[0019] Determine the attenuation coefficient of ultrasonic waves in the GIS busbar contact;

[0020] Correcting the transit time according to the attenuation coefficient;

[0021] By using the corrected transit time and the known distance between the two sides of the GIS busbar contact, a more accurate propagation velocity of the ultrasonic wave in the insulating gas is calculated.

[0022] Optionally, after step S9, the method further includes:

[0023] The temperature measurement is compared with the preset temperature rise threshold and an alarm signal is issued if the threshold is exceeded.

[0024] The present application also provides a GIS busbar contact temperature rise detection device, comprising:

[0025] The acquisition module is configured to install an ultrasonic transducer on both sides of the GIS busbar contact as an ultrasonic transmitter and a receiver; the transmitter is started to transmit an ultrasonic signal according to a preset transmission frequency; and the transit time of the ultrasonic signal from the transmitter to the receiver is measured through the receiver;

[0026] A calculation module is provided for calculating the propagation speed of the ultrasonic signal in the GIS bus contact based on the transit time; calculating the temperature value of the GIS bus contact according to a first correlation between the propagation speed and the temperature on the GIS bus contact; and calculating the optimized frequency according to a second correlation between the temperature value and the thermal interference effect of the ultrasonic frequency;

[0027] A judging module, judging whether the difference between the optimized frequency and the transmitting frequency is within a preset range; if the difference is not within the preset range, setting the optimized frequency as a new transmitting frequency, and repeating the steps of the calculating module;

[0028] The output module outputs the temperature value as a temperature measurement value if the difference is within the preset range.

[0029] Optionally, the acquisition module includes an ultrasonic transducer installed on both sides of the GIS busbar contact as a transmitting end and a receiving end of the ultrasonic wave, and further includes:

[0030] The positions for installing ultrasonic transducers on both sides of the GIS busbar contact are determined according to the heat flow path after the GIS busbar contact is abnormally heated.

[0031] Optionally, the preset transmission frequency is adjustable.

[0032] Optionally, the calculation module calculates the propagation speed of the ultrasonic signal in the GIS bus contact based on the transit time, including:

[0033] Determine the attenuation coefficient of ultrasonic waves in the GIS busbar contact;

[0034] Correcting the transit time according to the attenuation coefficient;

[0035] By using the corrected transit time and the known distance between the two sides of the GIS busbar contact, a more accurate propagation velocity of the ultrasonic wave in the insulating gas is calculated.

[0036] Optionally, the output module further includes:

[0037] The temperature measurement is compared with the preset temperature rise threshold and an alarm signal is issued if the threshold is exceeded.

[0038] The beneficial effects of this application are:

[0039] The present application provides a GIS bus contact temperature rise detection method, including: S1 installing an ultrasonic transducer on both sides of the GIS bus contact respectively, as an ultrasonic transmitter and a receiver; S2 starting the transmitter to transmit an ultrasonic signal according to a preset transmission frequency; S3 measuring the transit time of the ultrasonic signal from the transmitter to the receiver through the receiver; S4 calculating the propagation speed of the ultrasonic signal in the GIS bus contact based on the transit time; S5 calculating the temperature value of the GIS bus contact according to a first correlation between the propagation speed and the temperature on the GIS bus contact; S6 calculating the optimized frequency according to a second correlation between the temperature value and the thermal interference effect of the ultrasonic frequency; S7 judging whether the difference between the optimized frequency and the transmission frequency is within a preset range; S8 if the difference is not within the preset range, setting the optimized frequency to a new transmission frequency, and repeating steps S2 to S8; S9 if the difference is within the preset range, outputting the temperature value as a temperature measurement value. By utilizing the correlation between the propagation speed of ultrasound in the medium and temperature, real-time, accurate, and non-contact measurement of the GIS busbar contact temperature can be achieved, thereby improving the operating safety and reliability of GIS equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 This is a schematic diagram of the GIS busbar contact temperature rise detection process in this application;

[0041] Figure 2 This is a schematic diagram of the GIS busbar contact temperature rise detection device in this application. DETAILED DESCRIPTION

[0042] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that various forms of implementing the present disclosure should not be limited by the embodiments set forth herein. On the contrary, the embodiments are provided to more thoroughly understand the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0043] Please refer to Figure 1 As shown, the present application provides a GIS busbar contact temperature rise detection method, comprising:

[0044] S1 installs an ultrasonic transducer on both sides of the GIS busbar contact as the transmitting and receiving ends of the ultrasonic wave.

[0045] First, it is necessary to determine the heat flow distribution and propagation path of the GIS busbar contact under normal and abnormal heating conditions. Thermal imaging technology or thermal simulation software is used to perform thermal imaging analysis or thermal simulation on the GIS busbar contact to intuitively display the heat flow path when the contact is heated.

[0046] The installation position of the ultrasonic transducer should be selected at a position that can capture the ultrasonic signal caused by the contact temperature change to the maximum extent. Specifically, the transducer should be installed at the key node of the heat flow path, such as the bottleneck of heat transfer, the area with the most significant temperature change, or the interface where the medium properties change significantly.

[0047] like Figure 2 As shown, the ultrasonic transducer is fixed on both sides of the GIS busbar contact according to the predetermined installation position.

[0048] After installation, the ultrasonic transducer is tested and debugged to ensure that it can work properly and accurately receive and transmit ultrasonic signals.

[0049] In the two selected positions, an ultrasonic transducer is installed at one position as the transmitting end, which is responsible for starting and transmitting ultrasonic signals according to the preset transmitting frequency. Another ultrasonic transducer is installed at the other position as the receiving end, which is responsible for receiving the ultrasonic signal transmitted from the transmitting end through the insulating gas (i.e., the internal medium of the GIS).

[0050] S2 starts the transmitting end to transmit ultrasonic signals according to a preset transmitting frequency.

[0051] Set a specific ultrasonic transmission frequency. The selection of the transmission frequency is based on multiple factors, including the propagation characteristics of ultrasonic waves in the insulating gas inside the GIS, the detection accuracy requirements, and the performance limitations of the equipment itself. The preset transmission frequency should ensure that the ultrasonic signal can be stably propagated in the medium around the GIS busbar contact and can be effectively captured by the receiving end.

[0052] Then, according to the preset transmission frequency, the ultrasonic transducer installed on one side of the GIS busbar contact is activated as the transmitting end. This transducer converts electrical energy into ultrasonic signals and transmits them to the other side through the insulating gas around the GIS busbar contact.

[0053] It should be noted that the entire ultrasonic signal transmission and reception process is carried out without damaging the GIS shell structure, realizing non-contact detection of the temperature rise of the GIS busbar contact. This non-contact detection method avoids the risks that may be caused by direct contact, while also ensuring the safety and reliability of the detection process.

[0054] Furthermore, different GIS (gas insulated switchgear) bus contacts or different detection environments may have different responses to the frequency of the ultrasonic signal. The adjustable transmission frequency allows the detection system to flexibly respond to these changes and optimize the detection effect by adjusting the frequency.

[0055] In some cases, fine-tuning the transmission frequency can improve the propagation efficiency of ultrasonic signals in GIS bus contacts or enhance the correlation between signals and temperature changes, thereby improving the accuracy of temperature measurement.

[0056] In some implementations, the transmission frequency is set or adjusted by manually operating a knob, a button, or a touch screen interface on the device.

[0057] In some embodiments, the function of automatically adjusting the transmission frequency is implemented by a built-in algorithm or control logic to automatically adjust the transmission frequency according to the data collected during the detection process (such as signal strength, transit time, temperature change trend, etc.) to achieve the best detection effect.

[0058] S3 measures, through the receiving end, the transit time of the ultrasonic signal transmitted from the transmitting end to the receiving end.

[0059] The propagation time of the ultrasonic signal in the medium (such as insulating gas) around the GIS busbar contact is measured, that is, the transit time. The transit time will be used to calculate the propagation speed of the ultrasonic wave in the future, and then the temperature of the medium (and the contact) will be calculated.

[0060] When the transmitter starts and emits an ultrasonic signal at a preset transmission frequency, the signal will pass through the medium (such as insulating gas such as SF6) around the GIS busbar contact.

[0061] The receiving end is located on the other side of the medium and keeps monitoring the ultrasonic signal.

[0062] Once the receiving end detects the ultrasonic signal, it immediately records the time when the signal arrives. This time minus the time when the transmitting end transmits the signal, the transit time of the ultrasonic signal is obtained.

[0063] The transit time reflects the speed at which the ultrasonic wave propagates in the medium and is closely related to the temperature of the medium.

[0064] S4 calculates the propagation speed of the ultrasonic signal in the GIS bus contact based on the transit time.

[0065] The distance between the ultrasonic transducers installed on both sides of the GIS busbar contact is known. This distance is accurately measured during the installation process and is an important parameter for calculating the ultrasonic propagation velocity.

[0066] The propagation speed v of ultrasound in the medium can be calculated by the formula v=d / t, where d is the distance between the two transducers and t is the transit time of the ultrasonic signal.

[0067] Since the propagation speed of ultrasound is related to the temperature of the medium (here, the insulating gas around the GIS busbar contact), the temperature of the medium can be indirectly derived by measuring the propagation speed of ultrasound. This step is based on the physical property that ultrasound has different propagation speeds in media with different temperatures.

[0068] The calculated ultrasonic propagation velocity will be used in the subsequent steps to further derive the temperature value of the GIS busbar contact.

[0069] Furthermore, when ultrasonic waves propagate in a medium, their energy gradually decreases as the propagation distance increases. This phenomenon is called attenuation. The attenuation coefficient is a physical quantity used to quantify the degree of attenuation, which describes the proportion of ultrasonic energy reduction per unit distance.

[0070] The attenuation coefficient is usually obtained through experimental measurement.

[0071] In the actual detection environment of GIS busbar contacts, a pair of ultrasonic transducers are used, one for transmitting ultrasonic waves and the other for receiving. By changing the distance between the transmitting and receiving transducers and measuring the strength of the ultrasonic signal received at different distances, the attenuation coefficient can be calculated.

[0072] The transit time refers to the time it takes for an ultrasonic wave to be transmitted and received. Ideally, the transit time directly reflects the propagation speed of the ultrasonic wave in the medium.

[0073] In order to eliminate the influence of attenuation on the transit time, the transit time needs to be corrected according to the attenuation coefficient. The correction method is usually based on signal processing technology, such as filtering, gain adjustment or time delay compensation to restore or reconstruct the original ultrasonic signal, so as to obtain a more accurate transit time.

[0074] The propagation speed V of ultrasonic waves in the medium can be calculated by the following formula: V=D / T, where D is the distance between the transmitting and receiving transducers (known), and T is the corrected transit time.

[0075] S5 calculates the temperature value of the GIS bus contact according to the first correlation between the propagation speed and the temperature on the GIS bus contact.

[0076] The propagation speed of ultrasound in a medium is closely related to the temperature of the medium it passes through. This relationship is based on the principle of thermoacoustic effect in physics, that is, changes in the temperature of the medium will cause changes in its sound speed.

[0077] In the GIS busbar contact temperature rise detection, it is first necessary to obtain the first correlation between the ultrasonic propagation velocity and the contact temperature through experiments or theoretical calculations. This relationship is a mathematical expression, table data or fitting curve used to describe the ultrasonic propagation velocity at different temperatures.

[0078] Substitute the measured ultrasonic propagation velocity into the previously established correlation relationship (mathematical expression, table data or fitting curve), and the temperature value of the GIS busbar contact can be obtained through calculation.

[0079] In practical applications, due to the existence of measurement errors, environmental interference and other factors, the calculated temperature value has certain errors. Therefore, it is necessary to perform necessary error analysis and processing on the calculation results to improve the accuracy and reliability of temperature measurement.

[0080] S6 calculates the optimized frequency according to the second correlation between the temperature value and the thermal interference effect of the ultrasonic frequency.

[0081] When ultrasonic waves propagate in a medium, they will generate certain thermal interference due to factors such as absorption, scattering and nonlinear effects of the medium. This thermal interference is related to the frequency, power, propagation time of the ultrasonic waves and the temperature, density and other characteristics of the medium. In the temperature rise detection of GIS busbar contacts, as the contact temperature increases, the physical parameters of the medium (such as SF6 insulating gas) will change, thereby affecting the propagation characteristics and thermal interference effects of ultrasonic waves.

[0082] First, the propagation data of ultrasonic waves in the medium around the GIS busbar contact at different temperatures are collected through experimental means, including propagation speed, attenuation characteristics, and thermal interference effects. The collected experimental data are analyzed in depth to find the second correlation between ultrasonic frequency and thermal interference effect. This correlation is expressed in the form of functional relationship, tabular data, or fitting curve.

[0083] Furthermore, according to the second association relationship, finding the optimal ultrasonic frequency under given conditions can minimize the impact of thermal interference effects on the detection results while meeting other detection requirements.

[0084] Apply the calculated optimized frequency value to the actual test and verify its effectiveness and accuracy by comparing the experimental data. If a large deviation is found, it is necessary to readjust the experimental parameters or optimize the algorithm until a satisfactory result is obtained.

[0085] S7 determines whether the difference between the optimized frequency and the transmitting frequency is within a preset range.

[0086] Difference = optimization frequency - transmission frequency.

[0087] This difference reflects the gap between the current transmission frequency and the ideal optimized frequency used to improve detection accuracy or reduce thermal interference effects.

[0088] After calculating the difference between the optimized frequency and the transmitting frequency, the next step is to compare the difference with the preset range. If the difference is within the preset range, it can be considered that the current transmitting frequency is close enough to the optimized frequency and no adjustment is required or only fine-tuning is required. If the difference exceeds the preset range, it is necessary to consider whether a larger frequency adjustment is required to get close to the optimized frequency.

[0089] S8: if the difference is not within the preset range, the optimized frequency is set as a new transmission frequency, and steps S2 to S8 are repeated.

[0090] The calculated optimized frequency is set as a new transmission frequency, including: adjusting control parameters of the ultrasonic transmitting device to ensure that it can transmit ultrasonic signals at the new frequency.

[0091] After adjusting the transmission frequency, the ultrasonic transmitting equipment is calibrated to ensure that it can accurately transmit signals according to the new frequency.

[0092] After adjusting the transmission frequency and calibrating the equipment, the entire detection process needs to be reinitialized and re-executed from step S2, that is, re-transmitting the ultrasonic signal, measuring the transit time, calculating the propagation speed, calculating the temperature value, etc.

[0093] By repeating steps S2 to S8, an iterative optimization process is formed. In this process, the optimized frequency calculated each time will be compared with the current transmission frequency and adjusted according to the comparison result. As the number of iterations increases, the transmission frequency will gradually approach the optimal value, thereby improving the accuracy and reliability of detection.

[0094] During the iteration process, a convergence judgment condition needs to be set. When the difference between the optimization frequency and the transmission frequency stabilizes within the preset range or approaches zero after multiple consecutive iterations, it can be considered that the iteration process has converged and no further adjustment is required.

[0095] S9: if the difference is within the preset range, output the temperature value as a temperature measurement value.

[0096] The temperature value calculated by the previous steps is calculated based on the propagation speed of the ultrasonic signal in the GIS busbar contact and its correlation with the temperature.

[0097] Before output, the calculated temperature value may also need to be checked for validity. This includes checking whether there are abnormal data in the calculation process, whether the calculation result is within a reasonable range, etc. If the temperature value is judged to be invalid or unreasonable, it may be necessary to re-execute the previous steps or take other measures to obtain a valid temperature value.

[0098] When the temperature value is confirmed to be valid and meets the output conditions, the system or device will output this temperature value as the final temperature measurement value. The output method may include displaying it on a display screen, transmitting it to other devices or systems through an interface, storing it in a database, etc.

[0099] While outputting the temperature value, the system or device may also record related detection data, such as transmission frequency, transit time, propagation speed, etc. According to actual needs, the system or device can also generate reports containing temperature measurement values, detection data and other related information. These reports can be used to report to superiors, archive for future reference, or share with other departments.

[0100] Furthermore, after outputting the temperature value, the temperature of the GIS busbar contact continues to be monitored in real time. If the temperature value exceeds the preset safety range or threshold, the system will trigger an early warning mechanism and promptly notify relevant personnel to handle it.

[0101] Based on the temperature measurement results and the operating status of the equipment, a corresponding maintenance and servicing plan can be formulated, which helps to ensure the long-term stable operation of the equipment and extend its service life.

[0102] Furthermore, after step S9 is completed, the system has obtained the current temperature measurement value, which represents the real-time temperature of the monitored object (such as the interior of the device, the environmental space, etc.).

[0103] At the beginning of system design, one or more preset temperature rise thresholds have been set according to the characteristics of the monitored object, safety standards and operating requirements. These thresholds represent the maximum allowable temperature or temperature change rate. Exceeding this limit may cause safety problems or affect the normal operation of the system.

[0104] The system then compares the temperature measurement to the preset temperature rise threshold. If the threshold is not exceeded: the system may continue to perform other tasks or maintain the current state while continuing to monitor the temperature. If the threshold is exceeded: the system immediately enters the alarm mode and executes a series of preset response measures.

[0105] Once the temperature measurement value is confirmed to exceed the preset temperature rise threshold, the system will issue an alarm signal. This signal can be an audible alarm (such as a buzzer), a visual alarm (such as a flashing LED light, a warning message displayed on the screen), or an alarm notification sent through the network (such as email, SMS, system log, etc.), so as to promptly notify relevant personnel to pay attention and take necessary countermeasures.

[0106] Although the present invention is disclosed as above by the embodiments, it is not intended to limit the protection scope of the present invention. Any changes and modifications made by any technician familiar with the technology without departing from the concept and scope of the present invention should fall within the protection scope of the present invention.

Claims

1. A method for detecting temperature rise of GIS busbar contacts, characterized in that: include: S1. An ultrasonic transducer is installed on both sides of the GIS busbar contact, and the ultrasonic transducer includes a transmitting end and a receiving end; S2, starting the transmitting end to transmit ultrasonic signals according to a preset transmitting frequency; S3, measuring, by the receiving end, the transit time of the ultrasonic signal transmitted from the transmitting end to the receiving end; S4. Calculating the propagation speed of the ultrasonic signal in the GIS bus contact based on the transit time; S5. Calculating the temperature value of the GIS bus contact according to the first correlation between the propagation velocity and the temperature on the GIS bus contact; S6. Calculating an optimized frequency according to a second correlation between the temperature value and the thermal interference effect of the ultrasonic frequency; S7, determining whether the difference between the optimized frequency and the preset transmission frequency is within a preset range; S8, if the difference is not within the preset range, setting the optimized frequency to the preset transmission frequency, and repeating steps S2 to S8; S9. If the difference is within the preset range, output the temperature value as a temperature measurement value.

2. The GIS busbar contact temperature rise detection method according to claim 1 is characterized in that: Before step S1, the method further includes: The positions for installing ultrasonic transducers on both sides of the GIS busbar contact are determined according to the heat flow path after the GIS busbar contact is abnormally heated.

3. The GIS busbar contact temperature rise detection method according to claim 1 is characterized in that: In step S2, the preset transmission frequency is adjustable.

4. The GIS busbar contact temperature rise detection method according to claim 1 is characterized in that: Step S4 includes: Determine the attenuation coefficient of ultrasonic waves in the GIS busbar contact; Correcting the transit time according to the attenuation coefficient; By using the corrected transit time and the known distance between the two sides of the GIS busbar contact, a more accurate propagation velocity of the ultrasonic wave in the insulating gas is calculated.

5. The GIS busbar contact temperature rise detection method according to claim 1 is characterized in that: After step S9, the method further includes: The temperature measurement value is compared with a preset temperature rise threshold, and an alarm signal is issued if the preset temperature rise threshold is exceeded.

6. A GIS busbar contact temperature rise detection device, characterized in that: include: The acquisition module is configured to install an ultrasonic transducer on both sides of the GIS busbar contact as an ultrasonic transmitter and a receiver; the transmitter is started to transmit an ultrasonic signal according to a preset transmission frequency; and the transit time of the ultrasonic signal from the transmitter to the receiver is measured through the receiver; A calculation module, which calculates the propagation speed of the ultrasonic signal in the GIS bus contact based on the transit time; and calculates the temperature value of the GIS bus contact according to a first correlation relationship between the propagation speed and the temperature on the GIS bus contact; Calculating the optimized frequency according to a second correlation between the temperature value and the thermal interference effect of the ultrasonic frequency; A judging module, for judging whether a difference between the optimized frequency and the transmitting frequency is within a preset range; If the difference is not within the preset range, the optimized frequency is set as a new transmission frequency, and the steps of the calculation module are repeated; The output module outputs the temperature value as a temperature measurement value if the difference is within the preset range.

7. The GIS busbar contact temperature rise detection device according to claim 6, characterized in that: The acquisition module includes an ultrasonic transducer installed on both sides of the GIS busbar contact as the transmitting end and the receiving end of the ultrasonic wave, and also includes: The positions for installing ultrasonic transducers on both sides of the GIS busbar contact are determined according to the heat flow path after the GIS busbar contact is abnormally heated.

8. The GIS busbar contact temperature rise detection device according to claim 6, characterized in that: The preset transmission frequency is adjustable.

9. The GIS busbar contact temperature rise detection device according to claim 6, characterized in that: The calculation module calculates the propagation speed of the ultrasonic signal in the GIS bus contact based on the transit time, including: Determine the attenuation coefficient of ultrasonic waves in the GIS busbar contact; Correcting the transit time according to the attenuation coefficient; By using the corrected transit time and the known distance between the two sides of the GIS busbar contact, a more accurate propagation velocity of the ultrasonic wave in the insulating gas is calculated.

10. The GIS busbar contact temperature rise detection device according to claim 6, characterized in that: The output module further includes: The temperature measurement is compared with the preset temperature rise threshold and an alarm signal is issued if the threshold is exceeded.

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