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 (Dept. of Electrical and Electronic Engineering, Kiee University)
  • 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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그림 1 PAI/Nano Silica Vanish 제조 및 코일 제작 Fig. 1 PAI/Nano silica vanish manufacture and coil production

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그림 2 환경온도 & 절연파괴 수명 측정시스템 Fig. 2 Environmental temperature & insulation breakdown life measurement system

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그림 3 인가된 인버터서지 출력파형 Fig. 3 Applied inverter surge output waveform

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그림 4 4종류 코일의 온도 스트레스 가속열화에 의한 Arrhenius-Weibull 분포의 평균 절연수명 Fig. 4 Average Insulation life for Arrhenius-Weibull distribution induced to temperature stress of four types coils

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그림 5 Coil_1~Coil_4의 아레니우스 모델인 수명- 온도스트레스 가속계수 특성 Fig. 5 Life-temperature stress acceleration factor characteristic of arrhenius model of Coil_1~Coil_4

표 1 제조된 코일의 종류 및 내용 Table 1 Types and contents of manufactured coil

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표 2 Arrhenius-Weibull 분포의 수명-온도스트레스 계수 Table 2 Life-Temperature stress coefficient of Arrhenius- Weibull distribution

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표 3 Arrhenius-lognormal분포의 수명-온도스트레스 계수 Table 3 Life-Temperature stress coefficient of Arrheniuslognormal distribution

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표 4 Arrhenius-Exponential분포의 수명-온도스트레스 계수 Table 4 Life-Temperature stress coefficient of Arrhenius-Exponential distribution

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Table 5 Average lifetime of four types coils for three Arrhenius models–distribution 표 5 3종류 Arrhenius 모델-분포에 대한 4가지 코일의 평균수명

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표 6 Arrhenius-Weibull 관계에서 4종류 코일의 가속계수 Table 6 Acceleration coefficients of four types of coils in the Arrhenius-Weibull relation

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Supported by : 중부대학교


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