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Indicator Selection for Life Prediction of Polyimide Enameled Wire for Aviation Generators and Method for
Zihan Wang1, Yongzhi Liu1, Tianxing Li1
1Air Force Engineering University, Xi'an 710038, China.
Polymers
|June 12, 2026
Summary
Polyimide enameled wire insulation failure in aircraft generators is common. This study identifies parallel equivalent capacitance (Cp) as a key indicator for monitoring winding insulation health and predicting lifespan using accelerated aging and Bayesian regression.
Area of Science:
- Electrical Engineering
- Materials Science
- Aerospace Engineering
Background:
- Insulation failure in aviation generator windings is a frequent issue.
- Polyimide enameled wire is a common material in modern aircraft, necessitating reliability studies.
Purpose of the Study:
- To investigate the reliability and health monitoring of polyimide enameled wire insulation in aviation generators.
- To identify suitable parameters for monitoring insulation degradation and predict winding lifespan.
Main Methods:
- Designed accelerated thermal aging experiments on copper-core polyimide enameled wire samples (twisted-pair, coil, winding).
- Utilized B-spline fitting to visualize parameter variations and Bayesian nonlinear regression to update aging data.
Main Results:
- Parallel equivalent capacitance (Cp) was identified as the most suitable parameter for monitoring generator winding insulation.
- Aging of the insulation coating showed minimal impact on overall electrical system performance.
- Quantitative indicators for lifespan prediction were established based on Cp values reaching 1.2009 and 1.4089 times the initial value for 50% and 100% lifespan, respectively.
Conclusions:
- Parallel equivalent capacitance (Cp) offers a reliable method for real-time health monitoring of generator winding insulation.
- The study provides a quantitative framework for predicting the lifespan of polyimide enameled wire windings in aviation applications.
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