Dynamic flashover model considering pollution layer resistance variation for fixed washed high voltage insulators

This paper presents a dynamic model to compute the DC flashover voltage for a fixed washed high voltage insulator. This model provides a combination between the static flashover and dynamic arc models. The proposed model takes the pollution layer resistance variation with time during washing into consideration. This variation is experimentally measured at different equivalent salt deposit density (ESDD) values. A mathematical equation for computing the pollution resistance variation with time during washing process is proposed. The DC flashover voltage is computed using the proposed flashover model at different pollution levels. The proposed flashover model is experimentally validated considering the adopted ESDD values. Also, the obtained results show a good agreement between the proposed model and experimental results. The effect of washing water flow rate on flashover voltage is preliminary investigated. Finally, the present study improves fixed washing systems and decreases the flashover during the washing process.

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