大型发电机定子线棒主绝缘复合材料多工况老化特性研究

Study on the Aging Characteristics of the Main Insulation Composite Caterial of the Large Generator Stator Bar under Multiple Working Conditions

针对发电机定子线棒主绝缘复合材料的热/氧老化行为,本文分别开展了纯热与热氧环境下的人工加速模拟老化实验及测试分析研究。研究表明,老化过程中氧气的参与加速了由高温引起的自由基反应机理的老化降解反应,在老化过程中产生大量自由基,破坏分子链网络结构,且氧气的参与加速了热氧老化中自由基含量的快速下降,加重了材料的老化程度。随老化的进行,不同相态结构之间的相互作用力下降,在表层产生大量的碎片化错层结构。本研究对大型发电机绝缘系统的寿命评估提供了材料演变的基础数据,促进了评估精确性的提高。

Aiming at the thermal/oxygen aging of the main insulation composite material of generator stator bar,artificial accelerated simulated aging experiments under high temperature and high temperature/oxygen environment were carried out respectively.Studies show that oxygen accelerates the aging degradation reaction of the free radical reaction mechanism caused by high temperature during the aging process,generates a large number of free radicals during the aging process,and accelerates the destruction of the molecular network structure.The participation of oxygen accelerates the rapid decrease of free radical content and aggravates the aging degree of materials.As the aging progresses,the interaction force between different phase structures decreases,resulting in a large number of fragmented structures on the surface.This study provides the basic data of material evolution for the life assessment of large generator insulation system and promotes the improvement of the accuracy of the assessment.