Diagnosis Method of Decay-like Composite Insulators in a High-Humidity Environment Based on Characteristic
Yuming Zhang1, Sizu Hou2, Jianghai Geng1
1Hebei Key Laboratory of Power Transmission Equipment Security Defense, North China Electric Power University, Baoding 071003, China.
Polymers
|June 28, 2023
Summary
Diagnosing composite insulators requires a new method beyond infrared thermometry. A novel temperature rise gradient coefficient effectively distinguishes core rod defects from sheath aging, improving diagnostic accuracy.
Area of Science:
- Electrical Engineering
- Materials Science
- Non-destructive Testing
Background:
- Infrared thermometry is common for diagnosing composite insulator decay.
- Existing methods struggle to differentiate between decay-like insulators and those with aged sheaths, especially when slightly heated.
- This leads to limited diagnostic effectiveness and high false detection rates.
Purpose of the Study:
- To develop a new diagnostic characteristic quantity for composite insulators.
- To improve the accuracy of distinguishing between core rod defects and sheath aging.
- To address the limitations of current infrared thermometry diagnostic methods.
Main Methods:
- A full-scale temperature rise test was conducted on field-returned composite insulators under high humidity.
- An electro-thermal coupling simulation model was developed using dielectric characteristic parameters.
- Statistical analysis was performed on infrared images of abnormally hot composite insulators.
Main Results:
- Two defective insulators with similar temperature rise profiles were identified.
- A new infrared diagnostic feature, the temperature rise gradient coefficient, was obtained.
- This coefficient effectively identifies the source of abnormal heat in insulators.
Conclusions:
- The temperature rise gradient coefficient offers improved diagnostic capabilities for composite insulators.
- This new feature enhances the ability to differentiate between core rod defects and sheath aging.
- The findings contribute to more accurate and reliable non-destructive testing of electrical insulators.
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