The Evaluation of Daily Comparative Leakage Currents on Porcelain and Silicone Rubber Insulators Under Natural Environmental Conditions

Abstract

In this research, the leakage current (LC) and applied voltage waveforms on samples of installed outdoor porcelain and silicone rubber (SIR) insulators were measured by using a storage digital oscilloscope concurrent with humidity, temperature, and illuminance measurements. Essentially, the measurements were conducted daily, every three hours, for thirty days, and the data were analyzed using exponential regressions, box plots, and correlation coefficients. The porcelain and SIR insulator leakage currents varied from 23.7 A to 28.8 A and 8.4 A to 10.35 A for median values, respectively, while for outlier excluded values, they varied from 20.3 A to 40.0 A and 5.1 A to 17.1 A, respectively. Both leakage currents slightly increased as the exposure duration of the insulator rose, while the ratio decreased very slightly. Additionally, the leakage currents decreased moderately and slightly as the temperature and illuminance increased, respectively. However, the parabolic leakage currents increased as the humidity rose, especially at high humidity. Therefore, the porcelain insulator was more susceptible than the daily SIR, while the SIR insulator was more highly influenced by aging of the exposure duration. The rainy condition contributed to the highest leakage currents on both insulators, whereas the drizzle condition contributed to the highest leakage current on the SIR insulator. The total harmonic distortion (THD) and phase angle of the porcelain insulator leakage currents experienced differences of 5.8% and 7.8 degrees in the minimum and maximum humidity, respectively, but both quantities were less for the SIR insulator. INDEX TERMS humidity, leakage current, porcelain, silicone rubber I. INTRODUCTION High voltage outdoor insulators have an important role in electrical power transmission and distribution systems, including operational reliability, safety, and efficiency [1]. However, their functions are mostly influenced by environmental conditions [2-3]. Common insulator materials include glass and porcelain, which are ceramic materials that have been used for hundreds of years. Moreover, composite and cast cycloaliphatic epoxy resin (epoxy resin, ER), as a polymeric category, has been used in the last few decades [3-4]. These insulators have sheds for reducing the electric field stress and tolerating the accumulation of pollution [5]. Currently, research conducted on insulator leakage currents based on daily time functions is limited. Vosloo et al. [6] illustrated the average peak leakage currents on some insulators, and Roman et al. [7] monitored the insitu dc leakage current magnitudes, namely, rain, humidity, and temperature, on composite and glass insulators. According to Castillo-Sierra et al. [8], the ceramic insulator leakage currents were measured using a clamp meter, as were the temperature and humidity, followed by a regression analysis. Further research by Vosloo and Holtzhausen [9] showed that the peak leakage current of porcelain insulators, including precipitation, relative humidity (RH), ul...

Influence of Mounting Incline and Natural Environmental Factors on Pin-Type Silicone Rubber Insulator Leakage Currents Using Internet-Based Monitoring

“…Generally, the temperature reached its maximum around midday, when the humidity reached its minimum. These trends are consistent with those in [13]. Therefore, the temperature and humidity sensors and the system were operated appropriately.…”

“…The leakage currents of the insulators increased as the humidity [12], [13] and rainfall [12], [14] increased. Moreover, the increasing exposure duration caused the leakage currents to rise [1], [12], [13], [15], [16], [17], [18], [19], [20]. Nevertheless, this exposure decreases insulator resistance and weathering due to long-term ultraviolet exposure [4].…”

“…These pollutant levels determine flashover voltages [5], [10], [11]. The leakage currents of the insulators increased as the humidity [12], [13] and rainfall [12], [14] increased. Moreover, the increasing exposure duration caused the leakage currents to rise [1], [12], [13], [15], [16], [17], [18], [19], [20].…”

Real-Time Salt Contamination Monitoring System and Method for Transmission Line Insulator Based on Artificial Intelligence

“…From a literature survey, it is evident that insulator contamination is related to weather parameters such as temperature, relative humidity, pressure, wind speed, and ultraviolet [13][14][15][16]. Since the leakage current on the surface of the insulator is affected by the material, surface contamination, and surrounding environment, as well as its nonlinear characteristics, artificial intelligence algorithms such as machine learning technology have been applied to analyze the leakage current or estimate contamination on the surface of insulators in some related studies [10,11,13,[17][18][19][20][21][22].…”

On the Combination of Natural Environment Protection and Ethnic Development

“…Natural environment protection and ethnic integration play a very important role in China's economic and social development. However, with the continuous improvement of the socialist market economic system and the acceleration of industrialization since the reform and opening up, all aspects of China have improved the quality of national life to a new level, but there are also a series of ecological and environmental problems, Therefore, we should strengthen the protection of the natural environment and the development and utilization of ecological civilization resources to promote sustainable development [3,4].…”