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Polymeric Insulator Conditions Estimation by Using Leakage Current Characteristics Based on Simulation and
Ali Ahmed Salem1, Kwan Yiew Lau1, Zulkurnain Abdul-Malek1
1Institute of High Voltage and High Current, School of Electrical Engineering, Universiti Teknologi Malaysia, Johor Bahru 81310, Malaysia.
Polymers
|February 26, 2022
Summary
This study introduces novel time-frequency indicators derived from leakage current to assess the health of polluted polymeric insulators. These methods effectively evaluate insulator condition, offering an alternative diagnostic approach.
Area of Science:
- Electrical Engineering
- Materials Science
- Environmental Science
Background:
- Polluted polymeric insulators are prone to electrical failures.
- Assessing insulator health is crucial for power system reliability.
- Traditional methods may not fully capture the complex degradation patterns.
Purpose of the Study:
- To develop and validate time-frequency based leakage current indicators for assessing polluted polymeric insulator health.
- To analyze the effectiveness of these indicators under various environmental conditions.
- To identify the most performant indicator for practical application.
Main Methods:
- Laboratory testing of a 33 kV polymer insulator string under simulated pollution and wetting conditions.
- Extraction of temporal features (curve slope index F1, crest factor indicator F2) from leakage current.
- Analysis of frequency domain features (odd harmonic indicators F3, harmonic ratio F4) of the leakage current.
- Evaluation of indicator performance using a confusion matrix.
Main Results:
- The developed time-frequency leakage current indicators effectively assessed insulator conditions.
- Both time-domain (F1, F2) and frequency-domain (F3, F4) indices demonstrated capability in evaluating insulator health.
- The confusion matrix analysis helped determine the best-performing indicator.
Conclusions:
- The proposed leakage current analysis method provides an effective alternative for estimating the health of polluted polymeric insulators.
- Time-frequency characteristics of leakage current offer valuable insights into insulator degradation.
- This approach enhances diagnostic capabilities for power system maintenance.
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