PROJECT TITLE :

Empirical flashover model of EHV post insulators based on ISP parameter in cold environments

ABSTRACT:

The main objective of this contribution is to gift an empirical model of ice-lined insulator flashover in accordance with an vital flashover index, referred to as icing stress product (ISP). The ISP as the product of the ice mass per centimeter of insulator length and the electrical conductivity of the melted ice accretion is employed to establish an empirical model to determine the flashover voltage underneath icing conditions. To attain this model, many tests were administrated on post station insulators usually employed in Hydro-Quebec 735-kV substations, below DC and AC voltage, to see the connection between flashover stress and the ISP. The ISP-primarily based method offers a smart tool not only to pick out insulators for locations exposed to freezing conditions, however conjointly to check flashover results obtained beneath totally different check conditions. Moreover, to check the optimizing methodology of insulator flashover, the influence of air gaps on the flashover stress of ice-lined post insulators is investigated. The results reveal that the number of air gaps significantly affects the flashover stress. The test results are highly meaningful as they'll be used as a reference for ranking several different insulator varieties and configurations in order to pick the acceptable one for cold environments. Moreover, several mitigation options to boost insulator reliability in cold environments are provided.