摘要
为改善多胶模压主绝缘的环氧桐马酸酐胶黏剂的导热性能,将两种粒径h–BN(六方氮化硼)粉体按照固定比例混合后,添加到胶黏剂中制作高导热胶黏剂材料。采用导热仪、频域介电谱、扫描电子显微镜、耐高电压测试仪研究了h–BN粉体的添加量对高导热胶黏剂的导热性能、介质损耗因数、复介电常数、绝缘电阻、击穿强度的影响,运用电介质极化理论分析复合材料微观结构形态变化和宏观介电性能之间的关系,并结合扫描电镜从微观角度观测了复合材料断面中h–BN颗粒与胶黏剂之间的界面形貌变化。研究结果表明:随着h–BN混合粉体添加量(质量分数,下同)逐渐增多,h–BN–胶黏剂的导热系数不断增加,质量分数在80%~100%时增加速率较快;频域介电谱(frequency domain spectroscopy,FDS)曲线可较好反应h–BN不同添加量对h–BN–胶黏剂的介电参数的影响;h–BN–胶黏剂的击穿场强先降低然后逐渐提高至与纯胶黏剂的击穿场强几乎一致的水平。h–BN添加量在70%以上时,高导热胶黏剂不但能获得较好的导热性,其他性能均满足大型发电机主绝缘的要求。
To increase thermal conductivity of the epoxy tung-maleic(namely,Tongma)anhydride adhesives used for the main insulation of resin-rich molding(RRM),two kinds of h–BN particle sizes were mixed in a fixed proportion and then added into the adhesives to observe high thermal conductivity adhesives.The thermal property,dielectric loss factor,complex permittivity,insulation resistance and breakdown strength of the thermal adhesives with different additive amounts of h–BN were studied by thermal conductivity meter,frequency domain spectroscopy(FDS),scanning electron microscope(SEM)and high voltage instrument.The relationships between the microstructural variation of composites and the macroscopic dielectric property were analyzed by the dielectric polarization theory.And the interface morphology change between h–BN particles and adhesives in the cross section of composites was observed by scanning electron microscopy.The results show that the thermal conductivity of h–BN–adhesives gradually increases with the increase of h–BN powder content,and the increase rates are rapid at 80%~100%.The influence of h–BN content on the dielectric parameters of h–BN–adhesives can be revealed by FDS curves.The breakdown field strength of h–BN–adhesives decreases first and then increases gradually to nearly the same level of pure adhesives.The high thermal conductivity adhesives not only possess thermal conductivity but also posses other properties which can meet requirements of the large generator main insulation when the additive amount of h–BN is more than 70%.
作者
付强
梁良
王占一
陈庆国
FU Qiang;LIANG Liang;WANG Zhanyi;CHEN Qingguo(Harbin Institute of Large Electric Machinery,Harbin 150040,China;Key Laboratory of Engineering Dielectrics and Its Application,Ministry of Education,Harbin University of Science and Technology,Harbin 150080,China;State Key Laboratory of Hydropower Equipment,Harbin 150040,China;National Engineering Research Center Hydropower Equipment,Harbin 150040,China)
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2021年第2期652-662,共11页
High Voltage Engineering
基金
黑龙江省自然科学基金重点项目(ZD2018011)
工程电介质及其应用教育部重点实验室开放课题(哈尔滨理工大学,KF20151101)。
关键词
多胶模压主绝缘
高导热胶黏剂
六方氮化硼(h–BN)
频域介电谱
击穿场强
resin-rich molding main insulation
high thermal adhesive
hexagonal boron nitride(h–BN)
frequency domain spectroscopy(FDS)
breakdown field strength
