Estimation of Insulation Life of PAI/Nano Silica Hybrid Coil by Accelerated Thermal Stress

가속된 열적 스트레스에 의한 PAI / Nano Silica 하이브리드 코일의 절연수명 추정

Park, Jae-Jun

  • Received : 2018.11.11
  • Accepted : 2018.12.25
  • Published : 2019.01.01


In this paper, four types of insulation coils were fabricated by adding various kinds of glycols to improve the flexibility and adhesion of insulating coils in varnish dispersed with PAI / Nano Silica_15wt%. The applied voltage and frequency were 1.5 kV / 20 kHz for accelerated life evaluation. Through the 6th temperature stress level, the cause of the insulation breakdown of the coil was ignored and only the breakdown time was measured. The Arrhenius model was chosen based on the theoretical relationship between chemical reaction rate and temperature for estimating the insulation life of the coil due to accelerated thermal stress. Three types of distributions (Weibull, Lognormal, Exponential) were selected as the relationship between thermal stress model and distribution. The average insulation lifetime was estimated under the temperature stress of four types of insulation coils through the relationship between one kind of model and three kinds of distributions.


Evaluation of insulation life;PAI/Nano silica hybrid coil;Accelerated thermal stress;Arrhenius model-weibull distribution


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