Abstract
In this work, the extent of natural cleansing effect of rainfall, wind and fog or a combination of these on an insulator string were investigated. Results showed that pollution losses progress with time, with a considerable fraction of losses occurring within 15 minutes of testing. While wind alone played little or no role in surface cleansing, it increases the extent of cleansing by rainfall. The topsides of insulators were found to be more affected by natural cleansing compared to the underside. Equivalent Salt Deposit Density (ESDD) and Non-Soluble Deposit Density (NSDD) measurements were carried out. ESDD was found to be higher in the lower disc irrespective of the weather condition the insulator string has been subjected to. NSDD measurements established no pattern on how natural cleansing was impacted by disc position on a string, demonstrating the random nature of pollution-cleansing cycle of outdoor insulators. Insulator performance was assessed by high voltage AC tests and monitoring of partial discharge events using Radio Frequency antennas and a High Frequency Current Transformer (HFCT). Measured output by the HFCT showed that leakage current decreases uniformly with time, and the speed at which this occurs is an indication of the intensity of natural cleansing activity.
Highlights
Pollution is a major cause of insulation breakdown and increases the likelihood of a flashover incidence in affected insulators
This is typical of disc insulator strings in the field after rain with disparity increasing as the rainy season progresses
The natural cleansing activity of precipitation and wind has been identified in this work as a highly crucial and economically important process in insulator pollution accumulation and monitoring
Summary
Pollution is a major cause of insulation breakdown and increases the likelihood of a flashover incidence in affected insulators. A non-standard method is used in calculating surface pollution losses to better understand the extent of natural cleansing undergone by the test insulator when exposed to precipitation and wind elements. It could be observed that the combined action of rainfall and wind has higher cleansing effect than rainfall alone while fog exposure has the least impact on washing of pollutants from the equipment surface.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
