Gas sensor temperature compensation method for GIS equipment discharge monitoring

Abstract

The invention discloses a gas sensor temperature compensation method for GIS equipment discharge monitoring. The method comprises the following steps: collecting a gas sensor signal and an environment temperature signal; constructing and updating a data set by using a sliding time window; processing the data set by using a least square method, and fitting the relationship between the sensor signal and the external temperature; and predicting a signal of the sensor under the influence of temperature, comparing the signal with a real signal of the sensor, and judging whether to-be-detected gas is generated or not and performing discharge early warning. The method can be applied to the field of on-line monitoring and fault diagnosis of power equipment, and has very high application value.

Description

Technical Field

[0001] The present disclosure belongs to the field of online monitoring and fault diagnosis of power equipment, and particularly relates to a gas sensor temperature compensation method for discharge monitoring of GIS equipment. Background Art

[0002] As power system voltage levels increase, gas-insulated equipment (GIS), using SF6 as the insulating medium, plays an increasingly important role. GIS, the most common gas-insulated equipment, is typically filled with SF6 gas. As GIS equipment becomes more prevalent and ages, numerous power outages have occurred due to SF6 insulation breakdown. Previous research has shown that when partial discharge occurs within GIS equipment, the SF6 filling decomposes to produce a series of decomposition products, including SO2 and H2S. By measuring the composition of these decomposition products, potential insulation faults within the equipment can be identified, ensuring reliable operation.

[0003] Traditional methods for detecting SF6 decomposition products rely on large, precision equipment, which is costly, complex, and lacks portability, making them difficult to meet the demands of online monitoring of power equipment. Gas sensors, with their compact size and low cost, offer a reliable approach for online monitoring of GIS equipment. Gas identification is crucial for discharge monitoring. The actual operating environment of power equipment is complex, and gas sensor signals can drift with ambient temperature fluctuations, causing gas identification algorithms to fail and leading to false alarms. Therefore, temperature compensation of gas sensor signals is crucial for their application in GIS discharge monitoring. Summary of the Invention

[0004] In view of the above problems, the present disclosure aims to provide a gas sensor temperature compensation method for GIS equipment discharge monitoring.

[0005] To achieve the above objectives, the present disclosure provides the following technical solutions:

[0006] A gas sensor temperature compensation method for GIS equipment discharge monitoring includes the following steps:

[0007] S100. Collect gas sensor signals and ambient temperature data;

[0008] S200. Based on the collected gas sensor signal and ambient temperature data, a data set of gas sensor signals and ambient temperature changes is constructed;

[0009] S300. Fitting the relationship between the gas sensor signal and the ambient temperature based on the data in the data set;

[0010] S400. Based on the fitted relationship, the predicted value of the gas sensor signal at the predicted time under the influence of the ambient temperature is calculated and compared with the actual signal of the gas sensor to determine whether decomposition gas is generated;

[0011] S500. When it is determined that decomposition gas is generated, a discharge fault warning is issued.

[0012] Preferably, in S100 , the gas sensor signal and the ambient temperature data are collected by the monitoring module.

[0013] Preferably, the monitoring module includes a gas sensor and a temperature sensor.

[0014] Preferably, the data set is updated in real time as the number of acquisitions increases.

[0015] Preferably, constructing a data set of gas sensor signals and ambient temperature changes includes the following steps:

[0016] Based on the collected signal, a sliding time window is established and the collected data is filled in the time window; as time goes by, the time window gradually moves and the gas sensor data and temperature data in the window are updated.

[0017] Preferably, the relationship between the gas sensor signal and the ambient temperature is fitted using the least squares method.

[0018] Preferably, fitting the relationship between the gas sensor signal and the ambient temperature comprises the following steps:

[0019] According to experimental analysis, when there is no gas response interference, the gas sensor resistance and ambient temperature are approximately linearly related. The formula for the fitting straight line is:

[0020]

[0021] Where R is the resistance value of the gas sensor, T is the ambient temperature value, k is the slope of the fitting line, and b is the intercept of the fitting line;

[0022] The slope of the fitted straight line is calculated as:

[0023]

[0024] In the formula, m is the number of data for calculating the fitting line, is the average temperature of m data points, is the average value of the resistance in m data points;

[0025] After calculating the slope, according to With the slope k already determined, the intercept b can be found using the method of undetermined coefficients.

[0026] Preferably, determining whether decomposition gas is generated comprises the following steps:

[0027] Based on the fitted relationship between the gas sensor resistance and the ambient temperature calculated from the first m groups of data, the gas sensor resistance value corresponding to the ambient temperature value at the time to be predicted within the time window is predicted;

[0028] The predicted gas sensor resistance value And the gas sensor resistance value collected in real time by the device For comparison, calculate the error percentage c:

[0029]

[0030] The warning threshold is measured by the gas-sensing experiment. The discharge decomposition gas is introduced into the sensor, and the error percentage in the presence of decomposition gas is calculated. If the maximum error percentage is Y, 5% of Y is set as the warning threshold.

[0031] In actual applications, the sensor device collects data and calculates the error percentage in real time. If the error percentage c is less than a threshold, the prediction is accurate and the sensor resistance change conforms to the temperature correction law. If the error percentage c is greater than the threshold, the fitted line fails, indicating the presence of decomposition gas in the GIS, and a discharge fault warning is issued.

[0032] The present disclosure also discloses a gas sensor temperature compensation system for GIS equipment discharge monitoring, comprising:

[0033] Acquisition module, used to collect gas sensor signals and ambient temperature data;

[0034] A construction module is used to construct a data set of gas sensor signals and ambient temperature changes, and the data set is updated in real time as the number of acquisitions increases;

[0035] A calculation module is used to fit the relationship between the gas sensor signal and the ambient temperature, and calculate the predicted value of the gas sensor signal at the time to be predicted under the influence of the ambient temperature;

[0036] A comparison module is used to compare the predicted value of the gas sensor signal with the actual signal of the gas sensor to determine whether decomposition gas is generated;

[0037] The alarm module is used to issue a discharge fault warning when it determines that decomposition gas is generated.

[0038] The present disclosure also discloses a computer storage medium, wherein the storage medium includes computer instructions, which, when executed on a computer, enable the computer to execute any of the methods described above.

[0039] The present disclosure also discloses an electronic device, wherein the electronic device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements any of the methods described above when executing the program.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] This paper studies the impact of temperature changes on sensor signals, avoids the false alarm problem caused by temperature changes during GIS equipment discharge warning, and proposes an application method of gas sensors in GIS equipment discharge fault warning, which has high application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a flow chart of a gas sensor temperature compensation method for GIS equipment discharge monitoring provided by one embodiment of the present disclosure;

[0043] Figure 2 This is a schematic diagram of a simulation experiment provided by an embodiment of the present disclosure;

[0044] Figure 3 This is a temperature compensation experiment result diagram provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0045] The following will refer to the attached Figures 1 to 3 Specific embodiments of the present disclosure are described in detail. Although specific embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. Instead, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0046] It should be noted that certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different nouns to refer to the same component. This specification and claims do not use the difference in nouns as a way to distinguish components, but use the difference in the functions of the components as the criterion for distinction. As mentioned throughout the specification and claims, "including" or "comprising" is an open term, so it should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the present invention, but the description is based on the general principles of the specification and is not intended to limit the scope of the invention. The scope of protection of the present disclosure shall be as defined by the attached claims.

[0047] To facilitate understanding of the embodiments of the present disclosure, further explanation will be given below using specific embodiments as examples in conjunction with the accompanying drawings, and the accompanying drawings do not constitute a limitation on the embodiments of the present disclosure.

[0048] A gas sensor temperature compensation method for GIS equipment discharge monitoring includes the following steps:

[0049] Use monitoring modules to collect gas sensor signals and ambient temperature data;

[0050] Build a data set of sensor signals and temperature changes, and update the data set in real time as the number of acquisitions increases;

[0051] Use the least squares method to fit the relationship between the sensor signal and the external temperature;

[0052] Calculate the predicted value of the sensor signal at the predicted time under the influence of temperature, and compare it with the actual sensor signal to determine whether decomposition gas is generated;

[0053] When it is determined that decomposition gas is generated, a discharge fault warning is issued.

[0054] In one embodiment, constructing a data set of sensor signals and temperature changes includes the following steps:

[0055] Based on the signals collected by the device, a sliding time window is established and the collected data is filled into the time window. As time passes, the time window gradually moves, and the sensor data and temperature data within the window are updated.

[0056] In another embodiment, fitting the relationship between the sensor signal and the temperature using a least squares method includes the following steps:

[0057] According to experimental analysis, when there is no gas response interference, the gas sensor resistance and temperature are approximately linearly related. The formula for the fitting straight line is:

[0058]

[0059] Where R is the sensor resistance, T is the external temperature, k is the slope of the fitted line, and b is the intercept of the fitted line.

[0060] The slope of the fitted straight line is calculated as:

[0061]

[0062] In the formula, m is the number of data for calculating the fitting line, is the average temperature of m data points, is the average resistance of m data points. If the data within the entire time window is used, overfitting will occur. Therefore, the first m groups of data within the time window are used for fitting calculations.

[0063] After calculating the slope, according to With the slope k already determined, the intercept b can be found using the method of undetermined coefficients.

[0064] For example, within a certain period of time, the temperature T data is [28.676, 28.675, 28.644, 28.643,28.620, 28.617, 28.585, 28.562, 28.532, 28.500], and the sensor resistance R data is [1370.47,1372.84, 1375.00, 1377.26, 1378.49, 1380.16, 1381.17, 1381.40, 1383.42,1386.00].

[0065] Using the least squares method, we get the slope k=-77.0295, b=3582.0814. Therefore, the fitting formula is .

[0066] Determining whether decomposition gas is generated includes the following steps:

[0067] Based on the fitting relationship between sensor resistance and temperature calculated from the first m groups of data, the sensor resistance value corresponding to the temperature value at the time to be measured within the time window is predicted.

[0068] The predicted resistance value And the sensor resistance value collected by the device in real time For comparison, calculate the error percentage c:

[0069]

[0070] For example, if the temperature at the time of measurement is 28.6, according to the above fitting formula, the predicted resistance R is 1379, while the actual collected resistance is 1375. The error percentage is calculated as:

[0071]

[0072] The warning threshold is measured by the gas-sensing experiment. The discharge decomposition gas is introduced into the sensor, and the error percentage in the presence of decomposition gas is calculated. If the maximum error percentage is Y, 5% of Y is set as the warning threshold.

[0073] In actual application, the sensor device collects data and calculates the error percentage in real time. If the error percentage c is less than the threshold, it means that the prediction is accurate and the sensor resistance change conforms to the temperature correction law. When the error percentage c is greater than the threshold, it means that the fitting line fails, decomposition gas exists in the GIS, and a discharge fault warning is issued.

[0074] In another embodiment, the flow chart of temperature compensation and GIS equipment discharge monitoring is as follows: Figure 1As shown, the device is first powered on and preheated. During this process, sensor signals and temperature data are collected, and the least squares method is used to determine the effect of temperature changes on the sensor signals. After preheating, the sensor collects real-time ambient temperature data. The temperature effect is used to predict the sensor signal, and the error percentage is calculated compared to the actual sensor signal. If a discharge fault occurs in the power equipment, the gas to be measured is generated, causing the error percentage to exceed a threshold. The device then determines that a discharge fault has occurred within the power equipment and issues a fault warning.

[0075] In another embodiment, in order to verify the reliability of the device discharge fault warning, a gas discharge experimental platform was built, such as Figure 2 As shown, it is used to simulate discharge faults that occur during the operation of power equipment and verify the early warning effect of the compensation scheme. The gas discharge experimental platform is a GIS real-type simulation platform, including: gas sensors, a closed chamber, and a host computer.

[0076] In this embodiment, a sealed chamber is filled with SF6 insulating gas, and discharges at different voltage levels are applied to the internal electrodes to simulate insulation faults of varying severity. While the discharge is occurring, the host computer displays monitoring data from the gas sensor to verify whether the device detects the generation of decomposition gas and issues a discharge fault warning.

[0077] The experimental results are as follows Figure 3 As shown, when there is no decomposition gas, the temperature compensation method can effectively predict the sensor signal variation pattern with an error within 2%. When a discharge fault occurs and decomposition gas is generated, the correction pattern no longer applies, and the error can reach 150%. The sensor will then send a fault message to the host computer, effectively providing a discharge fault warning. Experimental verification shows that this method can prevent temperature interference on sensor signals and accurately identify discharge faults in power equipment.

[0078] The present disclosure also discloses a gas sensor temperature compensation system for GIS equipment discharge monitoring, comprising:

[0079] Acquisition module, used to collect gas sensor signals and ambient temperature data;

[0080] The construction module is used to construct a data set of sensor signals and temperature changes, and the data set is updated in real time as the number of acquisitions increases;

[0081] The calculation module is used to fit the relationship between the sensor signal and the external temperature, and calculate the predicted value of the sensor signal at the time to be predicted under the influence of the temperature;

[0082] A comparison module is used to compare the predicted value of the sensor signal with the actual sensor signal to determine whether decomposition gas is generated;

[0083] The alarm module is used to issue a discharge fault warning when it determines that decomposition gas is generated.

[0084] The present disclosure also discloses a computer storage medium, wherein the storage medium includes computer instructions, which, when executed on a computer, enable the computer to execute any of the methods described above.

[0085] The present disclosure also discloses an electronic device, wherein the electronic device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements any of the methods described above when executing the program.

[0086] The above embodiments are intended only to help understand the use and core concepts of the present disclosure. The specific implementation and scope of application of the present disclosure may vary depending on actual circumstances, and the above embodiments do not limit the scope of application of the present disclosure. Any addition, modification, or replacement of a technical feature with equivalent content in the art without departing from the technical features of the present disclosure shall fall within the scope of protection of the present disclosure.

Claims

1. A gas sensor temperature compensation method for GIS equipment discharge monitoring, characterized in that: The method comprises the following steps: S100. Collect gas sensor signals and ambient temperature data; S200. Based on the collected gas sensor signal and ambient temperature data, a data set of gas sensor signals and ambient temperature changes is constructed; S300. Fitting the relationship between the gas sensor signal and the ambient temperature based on the data in the data set; S400. Based on the fitted relationship, the predicted value of the gas sensor signal at the predicted time under the influence of the ambient temperature is calculated and compared with the actual signal of the gas sensor to determine whether decomposition gas is generated; S500. When it is determined that decomposition gas is generated, a discharge fault warning is issued.

2. The method according to claim 1, characterized in that Preferably, in S100 , the gas sensor signal and the ambient temperature data are collected by the monitoring module.

3. The method according to claim 1, characterized in that The data set is updated in real time as the number of acquisitions increases.

4. The method according to claim 1, wherein Building a dataset of gas sensor signals and ambient temperature variations involves the following steps: Based on the collected signal, a sliding time window is established and the collected data is filled in the time window; as time goes by, the time window gradually moves and the gas sensor data and temperature data in the window are updated.

5. The method according to claim 1, wherein The least squares method is used to fit the relationship between the gas sensor signal and the ambient temperature.

6. The method according to claim 1, characterized in that Fitting the relationship between the gas sensor signal and the ambient temperature includes the following steps: According to experimental analysis, when there is no gas response interference, the gas sensor resistance and ambient temperature are approximately linearly related. The formula for the fitting straight line is: ； Where R is the resistance value of the gas sensor, T is the ambient temperature value, k is the slope of the fitting line, and b is the intercept of the fitting line; The slope of the fitted straight line is calculated as: ； In the formula, m is the number of data for calculating the fitting line, is the average temperature of m data points, is the average value of the resistance in m data points; After calculating the slope, according to With the slope k already determined, the intercept b can be found using the method of undetermined coefficients.

7. The method according to claim 6, characterized in that Determining whether decomposition gas is generated includes the following steps: Based on the fitted relationship between the gas sensor resistance and the ambient temperature calculated from the first m groups of data, the gas sensor resistance value corresponding to the ambient temperature value at the time to be predicted within the time window is predicted; The predicted gas sensor resistance value And the gas sensor resistance value collected in real time by the device For comparison, calculate the error percentage c: ； The warning threshold is measured by the gas sensing experiment. If the error percentage c is less than the threshold, it means that the prediction is accurate and the gas sensor resistance change conforms to the temperature correction law. When the error percentage c is greater than the threshold, it means that the fitting line fails, decomposition gas exists in the GIS, and a discharge fault warning is issued.

8. A gas sensor temperature compensation system for GIS equipment discharge monitoring, comprising: Acquisition module, used to collect gas sensor signals and ambient temperature data; A construction module is used to construct a data set of gas sensor signals and ambient temperature changes, and the data set is updated in real time as the number of acquisitions increases; A calculation module is used to fit the relationship between the gas sensor signal and the ambient temperature, and calculate the predicted value of the gas sensor signal at the time to be predicted under the influence of the ambient temperature; A comparison module is used to compare the predicted value of the gas sensor signal with the actual signal of the gas sensor to determine whether decomposition gas is generated; The alarm module is used to issue a discharge fault warning when it determines that decomposition gas is generated.

9. A computer storage medium, wherein: The storage medium includes computer instructions, which, when executed on a computer, enable the computer to perform the method according to any one of claims 1 to 7.

10. An electronic device, wherein: The electronic device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method according to any one of claims 1 to 7 when executing the program.

Images