Degradation and Stability of Polymeric High-Voltage Insulators and Prediction of Their Service Life through Environmental and Accelerated Aging Processes

Abstract

Polymeric composite insulators consisting of core fiber reinforced polymer insulators covered with polydimethylsiloxane (PDMS) housing are now replacing conventional ceramic insulators especially for high-outdoor power transmission lines due to some specific advantages. Unlike ceramics, polymers have relatively shorter life. Outdoor insulators experience different electrical, mechanical, chemical, and thermal stresses during service. The long-term service performance of these insulators and their service life estimation is an important issue, but it is complicated and time-consuming. The objective of the present investigation is to check the rate of property deterioration during service and to find the approximate lifetime. Working insulators with different ages were collected from service, and the changes in mechanical and electrical properties and hydrophobicity of the PDMS cover against aging time were measured. The service life estimated from the change in mechanical properties and surface hydrophobicity (using MATLAB software) was compared with the service life of a new compound subjected to accelerated aging tests. Prediction of service life is helpful for replacement of aged insulators from service to avoid interruption in power transmission.

Effect of thermo‐oxidative aging on surface characteristics of benzoxazine and epoxy copolymer

“…Additionally, further evidence of polymer cleavage was observed by the loss of the medium peak of CH bonding in the range of 1440–1480 cm −1 , which was then replaced with very broad and weak peaks within the same region. The oxidation of the main polymer backbone could result in the grafting and formation of polar groups such as aldehydes, ketones, and carboxylic acids 39,40 . The data shows the formation of new broad carbonyl peaks ranging from 1500 to 1700 cm −1 in both samples.…”

Switchable Cavitation in Silicone Coatings for Energy‐Saving Cooling and Heating

“…Long-term stability was also expected since PDMS shows excellent stability, especially to solar light. [36,37] The durability of SPDMS films under even more serious condition was further tested. For example, the samples were immersed in liquid nitrogen (−196 °C) or annealing at 200 °C for 24 h. The treated coatings retain their integrity and performance, including both solar reflection and solar absorption (Figure 3d; Figures S19 and S20, Supporting Information).…”

Environmental Effects on HV Dielectric Materials and Related Sensing Technologies

“…Polymer insulators covered with a polydimethylsiloxane (PDMS) housing, which are replacing Polymer insulators covered with a polydimethylsiloxane (PDMS) housing, which are replacing ceramic insulators, were investigated to assess their service life through an accelerated aging process [55]. In the study, working insulators with different ages were collected from service, and the changes in the mechanical and electrical properties and hydrophobicity of the PDMS cover against aging time were measured.…”