实验技术与管理2025，Vol.42Issue(5)：132-139,8.DOI:10.16791/j.cnki.sjg.2025.05.016
基于PECT优化方法的发电机定子线棒主绝缘缺陷检测
Detection of main insulation defects in generator stator bars based on the PECT optimization method
摘要
Abstract
[Objective]Detecting insulation defects in the stator bars of generators is crucial for ensuring operational safety and efficiency.However,the presence of metallic conductors in the main insulation complicates defect detection.To address this issue,this paper proposes an optimization method for capacitance signals under free-field conditions and sensitive field characteristics based on PECT.The goal is to enhance the accuracy of defect detection in stator bar insulation by mitigating the influence of metallic conductors.[Methods]A 3×4 planar capacitive sensor model was constructed to investigate the effects of metallic conductors in stator bar insulation on capacitance signals and sensitive field distributions under free-field conditions.The study compared capacitance signals and sensitive field characteristics under different scenarios:with and without metallic conductors in the free field.The proposed optimization strategy combines the sensitive field under free-field conditions without metallic conductors and capacitance signals generated under free-field conditions with metallic conductors for inversion imaging.This hybrid approach capitalizes on the advantages of both scenarios to enhance imaging accuracy.Numerical simulations and experimental validations were conducted to evaluate the effectiveness of the proposed method.Defects were introduced at various positions in insulation to test the algorithm's ability to detect and localize them accurately.[Results]Simulation and experimental results demonstrate the proposed method's effectiveness in detecting insulation defects at different positions in stator bar insulation.Key findings from this study include the following.1)Metallic conductors in main insulation significantly alter the capacitance signals and sensitive field distribution,which reduces defect detection accuracy.2)By integrating the optimized sensitive field under free-field conditions without metallic conductors with capacitance signals produced under conditions with metallic conductors,the proposed method successfully compensates for these alterations,leading to improved imaging quality.3)The method achieves the accurate localization and characterization of defects in various positions,demonstrating its robustness across different scenarios.4)The proposed optimization strategy provides a new technical approach for evaluating the insulation condition of the generator stator bars,with potential applications in other insulation systems.[Conclusions]This study presents an innovative method for detecting insulation defects in the generator stator bars using PECT.By optimizing capacitance signals and sensitive field characteristics under free-field conditions,the proposed method effectively addresses challenges posed by the presence of metallic conductors in the insulation.Simulation and experimental results validate the method's capability to detect and localize defects accurately,providing a promising solution for assessing the main insulation state of generators.This technique offers a new tool for enhancing the reliability and safety of generator operations.关键词
发电机绝缘/平面电容层析成像/缺陷检测/敏感场分析/无损在线检测Key words
generator insulation/planar electrical capacitance tomography/defect detection/sensitive field analysis/non destructive online testing分类
信息技术与安全科学引用本文复制引用
赵煦,闫丽梅,刘婧,李元园,杨一丹,刘国强,李佳宝,王柏松..基于PECT优化方法的发电机定子线棒主绝缘缺陷检测[J].实验技术与管理,2025,42(5):132-139,8.基金项目
国家自然科学面上基金(52377018,52377227) （52377018,52377227）
