桐马环氧玻璃丝粉云母绝缘材料的耐盐雾湿热老化特性

Ageing characteristics of tong-ma epoxy glass fiber power mica insulation materials under salt spray and humidity thermal condition

为了研究海洋能电机主绝缘材料耐盐雾湿热老化能力,对电机多胶模压(Resin-Rich Molding,RRM)桐马环氧玻璃丝粉云母(Tong-ma Epoxy Glass Fiber Power Mica,TEGM)绝缘材料进行模拟海洋气候的盐雾湿热老化试验,测试了不同老化周期下材料的吸水率变化,并结合扫描电子显微镜(Scanning Electron Microscope,SEM)的观测结果分析了材料老化前后微观形貌的变化。利用宽频介电阻抗谱仪测试不同老化周期和不同测试温度下的TEGM绝缘材料的频域介电参数变化,并运用电介质极化理论分析老化前后的微观结构形态变化和宏观介电性能之间的关系。研究结果表明,TEGM绝缘试样老化过程中的吸水性呈现快速吸湿、缓慢吸湿和饱和吸湿3个阶段;随着老化时间的延长,材料相对介电常数和介质损耗因数呈上升趋势,利用频域介电谱(Frequency Domain Spectroscopy,FDS)曲线可较好反映绝缘材料的老化状态;通过对测试数据的拟合,得到老化绝缘材料的介电参数与材料吸水率在低频下存在的二次方程关系。

In order to study the capability of the main insulation materials of the ocean energy generators under salt spray and humidity thermal ageing condition,the test for the resin-rich molding(RRM)tong-ma epoxy glass fiber power mica(TEGM)insulation materials was carried out under the simulated ocean climatic condition.The water absorption rate of the resin-rich molding insulation materials was measured under different ageing cycles.The surface morphology change before and after the ageing test was analyzed based on the observed results of the sample through the scanning electron microscope(SEM).The frequency dielectric characteristics of the TEGM insulation materials were measured by the broadband dielectric spectrometer at different ageing cycles and different measuring temperatures.The relationships of the microstructure variety and the macroscopic dielectric property were analyzed by the dielectric polarization theory.The results show that the water absorption rate of the TEGM insulation materi-als sample appears three stages,namely fast absorption stage,slow absorption stage and saturation absorption stage.The relative dielectric constant and loss factor show the rising tendency with the increasing ageing time,and the frequency domain spectroscopy(FDS)curve can reflect the insulation ageing state directly in the low frequency range.Through the curve fitting of measured data,it can be seen that there are the quadratic equation relationships between the dielectric parameters and the water absorption for the aging insulation materials in the low frequency range.