Nano-SiO2 particles were doped into epoxy resin (EP) to fabricate the main insulation used for high voltage (HV) motors. The EP-based nanocomposite with different mass ratios of nano-SiO2 particles (0.5, 1, 2.5, and 5 wt%) were prepared. Surface morphology and conductivity of samples were tested, and AC breakdown strength was measured at different temperatures. The mechanisms for the tailoring of dielectric properties of EP were discussed. The optimal doping scheme (0.5 wt%) was selected and used as the base material in preparation of a stator coil insulation for 6 kV motors. The dielectric properties, including dielectric loss and leakage current as well as partial discharge, were tested, and the potential application of nano-SiO2 particles in the stator coil insulation of HV motors was discussed. The test results showed that the doped nano-SiO2 particle into dielectric composite used as the main insulation material for HV motors can be an optimal candidate to improve the above mentioned properties especially dielectric losses and electrical breakdown strengths. The results in this paper offer references and a guiding significance for the application of nano-SiO2 in the insulation of HV motors.

中文翻译：

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表面改性纳米二氧化硅提高高压电机定子线圈绝缘的介电性能

将纳米 SiO2 颗粒掺杂到环氧树脂 (EP) 中以制造用于高压 (HV) 电机的主绝缘材料。制备了具有不同质量比的纳米 SiO2 颗粒（0.5、1、2.5 和 5 wt%）的 EP 基纳米复合材料。测试了样品的表面形貌和电导率，并测量了不同温度下的交流击穿强度。讨论了调整 EP 介电特性的机制。选择最佳掺杂方案 (0.5 wt%) 并将其用作制备 6 kV 电机定子线圈绝缘材料的基础材料。测试了介电性能，包括介电损耗和漏电流以及局部放电，并讨论了纳米二氧化硅颗粒在高压电机定子线圈绝缘中的潜在应用。测试结果表明，作为高压电机主要绝缘材料的掺杂纳米SiO2颗粒进入介电复合材料可以成为改善上述性能特别是介电损耗和电击穿强度的最佳候选者。研究结果为纳米SiO2在高压电机绝缘中的应用提供参考和指导意义。