Degradation of High Voltage Polymeric Insulators in Arid Desert's Simulated Environmental Conditions

Abstract

Problem statement: High Voltage (HV) polymeric insulators are replacing ceramic insulator commonly used for HV outdoor networks due to their ease of handling, reliability and cost. However, their long term performance and reliability are major concerns to power utilities. Approach: To investigate their performance in arid desert's conditions, two types of HV composite insulators were aged as per International Electrochemical Commission (IEC) standard-61109. Additional test samples were subjected to accelerated aging conditions simulating the actual Ultraviolet (UV) radiation intensity and temperature in the inland desert. Results: This study described the experimental results of the effects of thermo electric stress and UV radiations on the polymeric insulators aged under two conditions i.e., as per IEC standard and modified IEC standard that simulates the inland arid desert. The tests results after the artificial accelerated aging indicated that the dielectric response of thermoplastic insulators under the tested thermo-electric cum UV-irradiations outperforms Silicone rubber insulators. Conclusion: From the obtained results it will be easy to assess the performance and suitability of composite insulators for their applications in arid desert environments.

Leakage current signal parameter of various surface roughness conditions of field-aged polymer insulators

“…When the age is longer, the larger of will be acquired. This has been acknowledged by Khan [10] in his study using the new samples in which it can be observed that the nature of surface insulator much smoother, homogenous and minimal porous surface as compared to the aged insulators. Meanwhile, related to the environmental stress effect, the condition of will be getting severe when the stresses themselves are worst.…”

Surface roughness condition of field-aged polymer insulators at different installation area

“…Significantly, considering the identical environmental stress, the higher age of service insulator, the larger Ra and porosity of surface insulator will be appeared [13], [19]. This can be described through the loss of the polymer outer layer on the surface, in which it will look like the surface finish of the molding process.…”

“…Meanwhile, the condition of Ra will be severe due to the high stress environment regardless of how long it has been employed in the service. The accumulated pollution and dust have contributed to influencing the surface roughness of the insulation, thereby reducing the dielectric performance after a long period of time [13]. This is to be observed with the existence of LC on the surface of EPDM and silicon rubber (SiR) as pollution is not fully removed, even after continuous rain [20].…”

“…Insulator surface roughness [12], [13] and LC analysis [14], [15] are becoming common method to be applied. This study is intended to investigate the polymer insulator degradation conditions by measuring one of the degradation indication parameter focusing on the insulator surface roughness.…”

Accelerated ultraviolet weathering investigation on micro‐/nano‐SiO 2 filled silicone rubber composites

“…Moreover, studies have also been made on the multi‐stress degradation of polymeric insulators under dry conditions (UV and temperature) to simulate the arid desert and tropical weathering conditions [13–15]. Khan et al [16] simulated the arid desert weathering conditions to investigate the surface hydrophobicity variations of EPDM and SR insulators.…”