A method and system for monitoring the temperature of a high voltage switchgear

Abstract

The application belongs to the technical field of high-voltage switchgear, and particularly relates to a high-voltage switchgear temperature monitoring method and system. The system comprises an infrared temperature sensor and a data processing unit. The infrared temperature sensor is arranged at a position where the high-voltage switchgear is provided with an observation window, is used for measuring the internal conductor temperature in real time through the glass of the observation window, obtaining the measurement temperature at each moment, and sending the measurement temperature to the data processing unit. The data processing unit is used for converting the measurement temperature at each moment into the conductor temperature at each moment. The application utilizes the infrared temperature sensor to measure the internal conductor temperature through the glass of the observation window, and then calculates the conductor temperature by using the measurement temperature. This kind of mode can realize real-time and accurate monitoring of the conductor temperature of a single high-voltage switchgear, has small environmental influence, is high in reliability, is convenient for realizing deep primary and secondary fusion, provides historical data for decision-making, greatly reduces the manpower investigation and the data pressure of the master station.

Description

Technical Field

[0001] This invention belongs to the field of high-voltage switchgear technology, specifically relating to a method and system for monitoring the temperature of high-voltage switchgear. Background Technology

[0002] In power systems, high-voltage switchgear is widely used in transmission lines and power plant substation busbar connections. It enables segmented operation of the power grid and isolates faults for easy maintenance. When operating under high current for extended periods, high-voltage switchgear is prone to oxidation of its moving and stationary contacts due to high temperatures. In severe cases, this can cause the stationary contact to disintegrate, leading to short circuits and other faults. Therefore, temperature monitoring of high-voltage switchgear is essential. Currently, most high-voltage switchgear uses temperature monitoring with sensors deployed within the substation. This method presents challenges in data communication between devices, inconsistent data formats, low integration with primary equipment, susceptibility to external environmental influences, and difficulty in achieving comprehensive temperature monitoring and historical recording from conductor to casing for individual devices. Furthermore, it hinders customized condition assessments and fault early warnings for different devices. Summary of the Invention

[0003] The purpose of this invention is to provide a method and system for monitoring the temperature of high-voltage switchgear, in order to solve the problems of difficult communication between devices and difficulty in monitoring the temperature of individual devices caused by the existing method of using sensors arranged in the station for temperature monitoring.

[0004] To address the aforementioned technical problems, this invention provides a high-voltage switchgear temperature monitoring system, comprising an infrared temperature sensor and a data processing unit. The infrared temperature sensor is installed at a location on the high-voltage switchgear with an observation window, and is used to measure the internal conductor temperature in real time through the glass of the observation window, obtaining the measured temperature at various times, and sending it to the data processing unit. The data processing unit is used to convert the measured temperature at various times into the conductor temperature at each time.

[0005] Its beneficial effects are as follows: This invention deploys an infrared temperature sensor at the location of the observation window in the high-voltage switchgear. The infrared temperature sensor measures the internal conductor temperature through the glass of the observation window, and then calculates the conductor temperature using the measured temperature. This method enables real-time and accurate monitoring of the conductor temperature of a single high-voltage switchgear unit, is less affected by environmental factors, has high reliability, facilitates deep primary and secondary data fusion, provides historical data to aid decision-making, and significantly reduces manual troubleshooting and the data burden on the main station. Furthermore, since the data detected by the infrared temperature sensor can be displayed as an image, the temperature data can be presented more intuitively.

[0006] Furthermore, the conversion method used by the data processing unit is as follows: multiplying the measured temperature by the absorptivity to obtain the conductor temperature, where the absorptivity is: β=(1-τ1+τ2+τ3p-τ4l2 -τ5lp-τ6p 2 ) 1 / 4 Where τ1~τ6 are temperature compensation coefficients, p is the SF6 pressure value in the high-voltage switch chamber, and l is the distance from the infrared observation window to the conductor.

[0007] Its beneficial effects are: the absorptivity can be accurately calculated by using the SF6 pressure value in the high-voltage switch chamber and the distance from the infrared observation window to the conductor, and then the conductor temperature can be accurately calculated by using the absorptivity.

[0008] Furthermore, the observation window of the high-voltage switch is made of glass with an infrared transmittance greater than a certain level.

[0009] Its beneficial effects are: choosing glass with high infrared transmittance can improve the accuracy of infrared sensor detection.

[0010] Furthermore, it also includes a temperature measuring terminal and several probes. The probes are installed at locations on the high-voltage switchgear where there is no observation window, and are used to measure the temperature of various parts of the casing and the ambient temperature in real time, and send the data to the temperature measuring terminal, which then sends it to the data processing unit. The data processing unit is also used to input the current temperature sent by the temperature measuring terminal into the constructed conductor temperature prediction model to obtain the conductor temperature at the current moment. The conductor temperature prediction model is trained using historical temperatures of various parts of the casing, historical ambient temperatures, and corresponding historical conductor temperatures as training data.

[0011] Its beneficial effects are as follows: considering that conductor temperature affects ambient temperature and high-voltage switch housing temperature, conductor temperature is derived by using the temperature of various parts of the housing and ambient temperature. The conductor temperature prediction model is trained using historical data, thus enabling accurate prediction of conductor temperature.

[0012] Furthermore, the plurality of probes are used to measure the temperature at at least two locations, including the side of the housing, the top of the housing, and the bottom of the housing.

[0013] Its beneficial effect is that using the temperature of multiple parts of the shell to predict the conductor temperature can improve the accuracy of conductor temperature prediction.

[0014] Furthermore, the data processing unit includes a main control board, a serial port board, an optical port board, and a power supply board; the main control board interacts with the temperature measurement terminal through the serial port board, and interacts with the infrared temperature sensor through the optical port board; the power supply board is used to supply power to the data processing unit.

[0015] To address the aforementioned technical problems, this invention also provides a method for monitoring the temperature of high-voltage switchgear. An infrared sensor is deployed at the location of the high-voltage switchgear with an observation window. The infrared temperature sensor measures the internal conductor temperature in real time through the glass of the observation window, obtaining the measured temperature at each moment. The measured temperature at each moment is then converted into the conductor temperature at that moment.

[0016] Its beneficial effects are as follows: This invention deploys an infrared temperature sensor at the location of the observation window in the high-voltage switchgear. The infrared temperature sensor measures the internal conductor temperature through the glass of the observation window, and then calculates the conductor temperature using the measured temperature. This method enables real-time and accurate monitoring of the conductor temperature of a single high-voltage switchgear unit, is less affected by environmental factors, has high reliability, facilitates deep primary and secondary data fusion, provides historical data to aid decision-making, and significantly reduces manual troubleshooting and the data burden on the main station. Furthermore, since the data detected by the infrared temperature sensor can be displayed as an image, the temperature data can be presented more intuitively.

[0017] Furthermore, the conversion method used is as follows: the conductor temperature is obtained by multiplying the measured temperature by the absorptivity, where the absorptivity is: β=(1-τ1+τ2+τ3p-τ4l 2 -τ5lp-τ6p 2 ) 1 / 4 Where τ1~τ6 are temperature compensation coefficients, p is the SF6 pressure value in the high-voltage switch chamber, and l is the distance from the infrared observation window to the conductor.

[0018] Its beneficial effects are: the absorptivity can be accurately calculated by using the SF6 pressure value in the high-voltage switch chamber and the distance from the infrared observation window to the conductor, and then the conductor temperature can be accurately calculated by using the absorptivity.

[0019] Furthermore, probes and temperature measuring terminals are deployed at locations on the high-voltage switchgear where there are no observation windows. The probes and temperature measuring terminals are used to acquire the temperature of various parts of the casing and the ambient temperature. The acquired temperatures are then input into a constructed conductor temperature prediction model to obtain the internal conductor temperature. The conductor temperature prediction model is trained using historical casing temperatures, historical ambient temperatures, and corresponding historical conductor temperatures as training data.

[0020] Its beneficial effects are as follows: considering that conductor temperature affects ambient temperature and high-voltage switch housing temperature, conductor temperature is derived by using the temperature of various parts of the housing and ambient temperature. The conductor temperature prediction model is trained using historical data, thus enabling accurate prediction of conductor temperature.

[0021] Furthermore, the temperature of each part includes measuring the temperature of at least two parts among the side angles of the housing, the top of the housing, and the bottom of the housing.

[0022] Its beneficial effect is that using the temperature of multiple parts of the shell to predict the conductor temperature can improve the accuracy of conductor temperature prediction. Attached Figure Description

[0023] Figure 1 This is a block diagram illustrating the principle of the high-voltage switchgear temperature monitoring system of the present invention. Figure 2 This is a schematic diagram of the BP neural network used in this invention; Figure 3 This is a graph showing the relationship between the infrared band and the absorptivity. Detailed Implementation

[0024] This invention employs different temperature monitoring methods for different high-voltage switchgear to achieve accurate monitoring of the internal conductor temperature of the high-voltage switch. To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0025] System Implementation Example: The present invention provides a high-voltage switchgear temperature monitoring system, such as... Figure 1 As shown, the system includes a centralized data processing unit and a temperature monitoring module. The centralized data processing unit is located within the intelligent component cabinet of the high-voltage switchgear and includes one main control board, two optical port boards, two serial port boards, and one power supply board, supporting eight pairs of optical ports and 32 serial ports. The main control board has a built-in Linux operating system, supporting external display conversion or remote connection for human-machine interaction. It includes one serial port, one USB port, two pairs of optical ports, and a wireless transmission module, communicating with substation control equipment / digital twin platform via the MMS protocol. The main control board has a built-in temperature monitoring and analysis algorithm, enabling the location of abnormal temperature rise points and accurate comprehensive temperature status monitoring and assessment. It supports local storage of historical data and uploads the processing results to the station control layer device (server). The power supply board primarily provides power to the internal circuit modules. It has a wide power input, supporting DC220V / AC220V, and outputs 24V power.

[0026] Different temperature monitoring modules are installed at different locations on high-voltage switchgear, employing varying temperature monitoring methods. Distributed fiber optic temperature measurement points can be installed at critical locations on the casing of GIS busbars, circuit breakers, and other similar equipment. The fiber optic temperature measurement terminal connects to the fiber optic probe and communicates with the lumped data processing unit's serial port board via RS485 to collect the casing temperature and upload the real-time casing temperature to the lumped data processing unit. The fiber optic temperature measurement terminal supports up to 12 fiber optic temperature probes and up to 6 infrared temperature sensors. The infrared temperature sensors are placed in suitable locations for observation windows, such as disconnect switches and grounding switches, allowing direct observation of the contact / conductor surface temperature through specially designed infrared glass.

[0027] When installing the fiber optic temperature measurement point, a suitable deployment location can be selected based on different shell structures and installation space. Selectable locations include the top and bottom of the shell, ±40° on the side of the shell, and 0° on the side of the shell. An additional fiber optic probe needs to be installed at a radial distance of 1m-1.5m from the conductor to measure the ambient temperature. The lumped data processing unit incorporates an artificial neural network algorithm based on a GIS temperature field effect physical simulation model. This algorithm can decouple the temperature data from the optical signal, fit the internal conductor temperature by measuring the temperature at the shell location, and generate temperature curves and historical records. Specifically, the artificial neural network algorithm can use a BP neural network, as shown below. Figure 2 As shown, the BP neural network is trained using historical temperatures of various parts of the casing, historical ambient temperatures, and corresponding historical conductor temperatures as training data to obtain a conductor temperature prediction model. Then, the temperatures of various parts of the high-voltage switchgear casing and the ambient temperature are obtained and input into the constructed conductor temperature prediction model to obtain the internal conductor temperature.

[0028] Before installing the infrared sensor, the observation window material must be modified to high infrared transmittance glass, with germanium glass being the optimal choice. The specific relationship between the infrared band and the absorption rate is as follows: Figure 3 As shown, the lumped data processing unit incorporates an infrared compensation algorithm, which can calculate the conductor temperature by compensating for the temperature distribution image data captured by the infrared probe.

[0029] Conductor temperature T = Measurement temperature T × Absorbency β Absorption rate β=(1-τ1+τ2+τ3p-τ4l 2 -τ5lp-τ6p 2 ) 1 / 4 In the formula, τ * (* represents 1~6) is the temperature compensation coefficient; p is the SF6 pressure value of the disconnector switch chamber; l is the distance from the infrared observation window to the internal conductor (e.g., the contact).

[0030] Using the methods described above, the main control board can locate abnormal temperature rise points in the equipment and perform relatively accurate all-round temperature status monitoring and evaluation. It supports local storage of historical data and uploads the processing results to the station control layer device (server).

[0031] In summary, this invention combines infrared and fiber optic temperature measurement methods to achieve temperature monitoring of key components of high-voltage switchgear. It is highly integrated with primary equipment and develops a centralized data processing unit to achieve comprehensive temperature monitoring and data fusion. It is less affected by the environment, has high reliability, achieves deep primary and secondary fusion, provides historical data to assist decision-making, supports digital twins, greatly reduces manual troubleshooting and the data pressure on the main station, realizes comprehensive monitoring of the temperature status of high-voltage switchgear and fault location, and greatly improves the intelligence level of high-voltage switchgear.

[0032] Method Implementation Examples: The present invention provides a method for monitoring the temperature of high-voltage switchgear, the specific means of which are as follows: Infrared sensors are deployed at locations with observation windows in high-voltage switchgear. These sensors measure the internal conductor temperature in real time through the glass of the observation window, obtaining the measured temperature at various moments. The measured temperature at each moment is then converted to the conductor temperature using the following formula: Conductor temperature T = Measured temperature T × Absorbance β, where Absorbance β = (1 - τ1 + τ2 + τ3p - τ4l) 2 -τ5lp-τ6p 2 ) 1 / 4 , τ * (* represents 1~6) is the temperature compensation coefficient; p is the SF6 pressure value of the disconnector switch chamber; l is the distance from the infrared observation window to the internal conductor.

[0033] Probes and temperature measuring terminals are deployed at locations on high-voltage switchgear where there are no observation windows. The probes and temperature measuring terminals are used to acquire the temperature of various parts of the outer casing and the ambient temperature. The acquired temperatures are then input into a constructed conductor temperature prediction model to obtain the internal conductor temperature. The conductor temperature prediction model can be a BP neural network model, which is trained using historical temperatures of various parts of the outer casing, historical ambient temperatures, and corresponding historical conductor temperatures as training data.

Claims

1. A temperature monitoring system for high-voltage switchgear, characterized in that, It includes an infrared temperature sensor, a temperature measurement terminal, several probes, and a data processing unit; Infrared temperature sensors are installed at locations with observation windows in high-voltage switchgear, including disconnect switches and grounding switches, to measure the temperature of internal conductors in real time through the glass of the observation window, obtain the measured temperature at various times, and send it to the data processing unit. Several probes are installed in locations where high-voltage switchgear does not have observation windows, including key parts of the enclosure such as GIS busbars and circuit breakers, to measure the temperature of various parts of the enclosure and the ambient temperature in real time, and send the data to the temperature measurement terminal, which then sends it to the data processing unit. The data processing unit is used for: The internal conductor temperature at each moment is obtained by multiplying the measured temperature transmitted by the infrared temperature sensor by the absorptivity. The absorptivity is: β=(1-τ1+τ2+τ3p-τ4l 2 -τ5lp-τ6p 2 ) 1 / 4 τ1~τ6 are temperature compensation coefficients, p is the SF6 pressure value in the high-voltage switch chamber, and l is the distance from the infrared observation window to the conductor; The current temperature sent by the temperature measuring terminal is input into the conductor temperature prediction model based on the GIS temperature field effect physical simulation model to obtain the current internal conductor temperature.

2. The high-voltage switchgear temperature monitoring system according to claim 1, characterized in that, The observation window of the high-voltage switch is made of glass with an infrared transmittance greater than a certain level.

3. The high-voltage switchgear temperature monitoring system according to claim 1, characterized in that, The conductor temperature prediction model is trained using historical temperatures of various parts of the outer shell, historical ambient temperatures, and corresponding historical conductor temperatures as training data.

4. The high-voltage switchgear temperature monitoring system according to claim 1, characterized in that, The probes are used to measure the temperature at at least two locations, including the side of the housing, the top of the housing, and the bottom of the housing.

5. The high-voltage switchgear temperature monitoring system according to claim 1, characterized in that, The data processing unit includes a main control board, a serial port board, an optical port board, and a power supply board. The main control board interacts with the temperature measurement terminal through the serial port board and interacts with the infrared temperature sensor through the optical port board. The power supply board is used to supply power to the data processing unit.

6. The high-voltage switchgear temperature monitoring system according to claim 3, characterized in that, The conductor temperature prediction model is an artificial neural network.

7. A method for monitoring the temperature of high-voltage switchgear, characterized in that, Infrared sensors are deployed at locations with observation windows on high-voltage switchgear, including disconnecting switches and grounding switches. Infrared temperature sensors are used to measure the internal conductor temperature in real time through the glass of the observation window, obtaining the measured temperature at various times. The measured temperatures at each time time are then converted into the conductor temperature at that time using the following conversion method: multiplying the measured temperature by the absorptivity to obtain the conductor temperature. The absorptivity is: β=(1-τ1+τ2+τ3p-τ4l 2 -τ5lp-τ6p 2 ) 1 / 4 Where τ1~τ6 are temperature compensation coefficients, p is the SF6 pressure value in the high-voltage switch chamber, and l is the distance from the infrared observation window to the conductor; Probes and temperature measuring terminals are deployed at locations where high-voltage switchgear lacks observation windows, including key components of the casing such as GIS busbars and circuit breakers. The probes and temperature measuring terminals are used to acquire the temperature of various parts of the casing and the ambient temperature. The acquired temperatures are then input into a conductor temperature prediction model based on a physical simulation model of GIS temperature field effects to obtain the internal conductor temperature.

8. The method for monitoring temperature in high-voltage switchgear according to claim 7, characterized in that, The conductor temperature prediction model is trained using historical temperatures of various parts of the outer shell, historical ambient temperatures, and corresponding historical conductor temperatures as training data.

9. The method for monitoring temperature in high-voltage switchgear according to claim 7, characterized in that, The temperature measurements at each location include the temperature measurements at at least two locations: the side of the housing at various angles, the top of the housing, and the bottom of the housing.

10. The method for monitoring temperature in high-voltage switchgear according to claim 7, characterized in that, The conductor temperature prediction model is an artificial neural network.

Images