CN-122016074-A - Method for detecting abnormal heating area of composite insulator based on Raman spectrum

CN122016074ACN 122016074 ACN122016074 ACN 122016074ACN-122016074-A

Abstract

The invention relates to the technical field of composite insulator detection, and particularly discloses a method for detecting an abnormal heating area of a composite insulator based on Raman spectrum, which is suitable for a composite insulator with a silicon rubber sheath dyed by ferric oxide as pigment. The method comprises the steps of firstly selecting a sample to be detected, carrying out spectrum acquisition on a region to be detected on the surface of a silicone rubber sheath by using a Raman spectrometer without applying operation voltage, then processing optical data, respectively extracting characteristic peak intensities of ferric oxide in a 223+/-8 cm < -1 > and 292+/-12 cm < -1 > Raman displacement range, calculating a ratio of the two characteristic peak intensities, comparing the obtained ratio with a preset threshold value, judging whether an abnormal heating history exists in the region to be detected during the operation of the screen, and determining the preset threshold value through establishing a standard sample library and carrying out statistical analysis. The invention has objective detection result and is not interfered by electric field and environmental factors.

Inventors

WANG YIMING
XIA RU
YU YAPING
CHEN PENG

Assignees

安徽大学
南京东燚信息技术有限公司

Dates

Publication Date: 20260512
Application Date: 20260325

Claims (7)

1. The method for detecting the abnormal heating area of the composite insulator based on the Raman spectrum is characterized by comprising the following steps of: Step S1, selecting a composite insulator sample to be detected, wherein a silicon rubber sheath of the composite insulator sample is dyed by taking ferric oxide as pigment in the production process; s2, carrying out Raman spectrum acquisition on a region to be detected on the surface of the silicon rubber sheath of the composite insulator sample by using a Raman spectrometer, wherein no operation voltage is applied to the composite insulator sample in the acquisition process; s3, processing the acquired Raman spectrum data, and respectively acquiring a first characteristic peak intensity and a second characteristic peak intensity in a characteristic Raman spectrum of ferric oxide; s4, calculating the ratio of the first characteristic peak intensity to the second characteristic peak intensity to obtain a peak intensity ratio; And S5, comparing the peak intensity ratio with a preset threshold value, and judging whether the abnormal heating history exists in the region to be tested in the process of the compound insulator sample screening operation.
2. The method for detecting abnormal heating areas of composite insulators based on Raman spectroscopy according to claim 1, wherein in the step S3, the first characteristic peak intensity is a spectrum peak intensity with a Raman shift within a range of 223+ -8 cm < -1 >, and the second characteristic peak intensity is a spectrum peak intensity with a Raman shift within a range of 292+ -12 cm < -1 >.
3. The method for detecting abnormal heating areas of composite insulators based on Raman spectra according to claim 1 is characterized in that in the step S5, the judging rule of the preset threshold is that when the peak intensity ratio is smaller than 0.56, abnormal heating phenomena are judged to exist in the areas to be detected during the screening operation, the temperature difference between the temperature of the areas to be detected under the operation voltage and the temperature of the normal areas of the same composite insulator is larger than 1K, when the peak intensity ratio is larger than 0.65, abnormal heating phenomena are judged to not exist in the areas to be detected during the screening operation, and when the peak intensity ratio is larger than or equal to 0.56 and smaller than or equal to 0.65, slight heating signs exist in the areas to be detected during the screening operation, and the temperature difference between the temperature of the areas to be detected under the operation voltage and the temperature of the normal areas of the same composite insulator is smaller than 1K.
4. The method for detecting abnormal heating areas of composite insulators based on raman spectroscopy according to claim 1, wherein in the step S3, the first characteristic peak intensity and the second characteristic peak intensity are peak intensities of spectral peaks in a corresponding raman shift range, or are integrated area intensities of spectral peaks in a corresponding raman shift range.
5. The method for detecting abnormal heating areas of composite insulators based on raman spectroscopy according to claim 1, further comprising the step of establishing a standard sample library to determine the preset threshold before step S5, specifically: Step A1, selecting composite insulator samples with different operation years as calibration samples, wherein a silicon rubber sheath of the calibration samples is dyed by adopting pigment containing ferric oxide; a2, applying an operating voltage to the calibration sample through an infrared thermal imaging technology, and then measuring the temperature to calibrate a known heating area and a normal area in the calibration sample; Step A3, carrying out Raman spectrum acquisition on the known heating area and the normal area in a dense lattice mode, calculating the characteristic peak intensity ratio of each sampling point at the positions of 223+/-8 cm < -1 > and 292+/-12 cm < -1 > of the Raman displacement of ferric oxide, and establishing a mapping database of the peak intensity ratio and the heating state; And A4, analyzing the peak intensity ratio data in the mapping database by adopting a statistical analysis method, and determining the preset threshold value.
6. The method for detecting abnormal heating areas of composite insulators based on raman spectroscopy according to claim 1, wherein in the step S1, the composite insulator sample is a retired operation sample, an operation sample or a sample processed by an accelerated aging test.
7. The method for detecting abnormal heating areas of composite insulators based on raman spectroscopy according to claim 1, wherein in the step S2, the raman spectrometer is a portable raman spectrometer or a bench raman spectrometer.

Description

Method for detecting abnormal heating area of composite insulator based on Raman spectrum Technical Field The invention relates to the technical field of composite insulator detection, in particular to a method for detecting an abnormal heating area of a composite insulator based on Raman spectrum. Background The composite insulator is high-voltage insulation equipment made of a silicon rubber sheath and a glass fiber reinforced epoxy resin core rod wrapped by an umbrella skirt, and is a core insulation component of power transmission and transformation lines, large-scale power equipment and facilities. The composite insulator runs in the power grid for a long time, and with the increase of the running period, partial sample local temperature is observed to be significantly higher than other normal positions in the operation and maintenance process, and the phenomenon is called abnormal heating. The composite insulator with abnormal heating can obviously increase the power failure probability, and is an important hidden danger affecting the safe operation of the power grid, so that the accurate detection and positioning of the abnormal heating area of the composite insulator has important significance for guaranteeing the safe and stable operation of the power grid. At present, an infrared temperature measurement method is generally adopted in the industry to monitor the temperature distribution of the in-process composite insulator, however, the method has two inherent defects in practical application. Firstly, the composite insulator is limited by electric field factors, abnormal heating phenomenon can only occur when the composite insulator is connected to a high-voltage electric field, the composite insulator which is stopped or removed from an operation line cannot detect a heating state through an infrared thermometer, and when the electric field intensity changes, an infrared temperature measurement result also changes, so that the detection result lacks stability. Secondly, the temperature of the abnormal heating area of the composite insulator is influenced by the factors such as the ambient temperature, the humidity, the light, the air flow and the like, the infrared temperature measurement results under different meteorological conditions are different, and the detection cannot be normally carried out under the environment with high humidity or strong light irradiation. The defects cause the application scene of the existing infrared temperature measurement technology in the abnormal heating detection of the composite insulator to be strictly limited, the objectivity and the reliability of the detection result are difficult to ensure, and the development of a detection technology which is not limited by the running condition and the field environmental condition of the composite insulator and can accurately judge the abnormal heating area of the composite insulator is needed. Disclosure of Invention In order to overcome the defects in the prior art, the invention provides a detection method for an abnormal heating area of a composite insulator based on Raman spectrum. Acquiring 223+/-8 cm by acquiring Raman spectrum of a composite insulator silicone rubber sheath dyed by ferric oxide as pigmentWith 292+ -12 cmAnd (3) the intensities of the two characteristic peaks and calculating the peak intensity ratio, and judging whether the abnormal heating history exists in the region to be detected according to a preset threshold value. The invention overcomes the defects that the existing infrared temperature measurement technology is required to detect under the operating voltage and the detection result is easy to be interfered by the ambient temperature, humidity, illumination and air flow. In order to achieve the above purpose, the present invention provides the following technical solutions: a detection method of an abnormal heating area of a composite insulator based on Raman spectrum comprises the following steps: Step S1, selecting a composite insulator sample to be detected, and dyeing a silicon rubber sheath of the composite insulator sample by taking ferric oxide as pigment in the production process; s2, carrying out Raman spectrum acquisition on a region to be detected on the surface of the silicon rubber sheath of the composite insulator sample by using a Raman spectrometer, wherein no operation voltage is applied to the composite insulator sample in the acquisition process; S3, processing the acquired Raman spectrum data, and respectively acquiring first characteristic peak intensity and second characteristic peak intensity in the characteristic Raman spectrum of ferric oxide, wherein the first characteristic peak intensity is reduced along with the deepening of the thermal aging degree, and the second characteristic peak intensity is kept stable along with the change of the thermal aging degree; s4, calculating the ratio of the intensity of the first characteristic peak to the intensity of