A study on the effect of voltage waveshape atmospheric pressure and environment on flashover voltage of polymeric insulators

Abstract

Insulators are essential for maintaining the reliability of electrical newlinepower transmission and distribution networks. Amongst the various failure newlinemodes observed in widely used polymeric insulators (PI), failures resulting from newlineflashover and subsequent surface degradation account for 26% of the total newlinefailures (Insulator News and Market Report (INMR) 2023). In addition, the newlineFlashover Voltage (FOV) is one important parameter when dimensioning high newlinevoltage insulators. FOV is influenced by various factors such as insulator profile, newlinesurface hydrophobicity, voltage waveshapes, atmospheric conditions, newlineenvironmental conditions, and so on. An attempt is made to investigate the newlinechange in FOV voltage at different atmospheric pressures under different types newlineof voltages and various environmental conditions using both the experimental newlineand Finite Element Method (FEM) based computational methods. newlineIn general, atmospheric conditions are mainly characterized by newlinefactors such as temperature, humidity and pressure. The variation in these newlinefactors is often observed to increase at higher altitudes. With increasing newlinealtitudes, the reductions in FOV of insulators are reported in many newlineinvestigations and surveys. As per International Electrotechnical Commission newline(IEC) 60071-2 (2018) and CIGRE Reports (CIGRE WG D1.50 TB 888 newline2023), the effect of altitude can be well represented by the atmospheric newlinepressure as the effects of temperature and humidity are compensatory. newlineHence, the atmospheric pressure is a more influential parameter to analyse newlineFOV for different altitudes. newline