Article
Green & Sustainable Science & Technology
Jinshan Qin, Xiao Peng, Qinpan Qiu, Chao Tang
Summary: This paper investigates the mechanism of improving the properties of natural ester insulating oil by modifying it with nano hexagonal boron nitride grafted with silane coupling agent (APTES-hBN). Experimental results show that the addition of Nano APTES-hBN inhibits acid production and reduces the number of polar molecules in the oil. Mechanism study reveals that the addition of Nano APTES-hBN enhances the interfacial bonding between oil and paper insulation, and has strong adsorption capacity.
Article
Engineering, Electrical & Electronic
Ed Casserly, Juan Acosta, Andy Holden, Brad Greaves, Tom Prevost
Summary: The thermal index of thermally upgraded Kraft paper was determined using IEEE Standard C57.100 Annex A.4.2 for five mineral insulating liquids and two natural esters, and compared with the values in IEEE Standard C57.91.
IEEE ELECTRICAL INSULATION MAGAZINE
(2022)
Article
Energy & Fuels
Tobias Muenster, Peter Werle, Kai Haemel, Joerg Preusel
Summary: The article discusses the aging behavior of oil-paper insulations in transformers using different insulating fluids and highlights differences in aging rates and marker formations among mineral oil and ester-based insulating fluids, which can enhance asset management strategies.
Article
Materials Science, Multidisciplinary
S. O. Oparanti, A. A. Khaleed, A. A. Abdelmalik
Summary: In the quest for a clean alternative insulating oil, the potential of transformer oil-based nanofluids using natural ester as a green alternative has been thoroughly investigated. This study focused on improving the physicochemical properties, dielectric loss, and breakdown voltage of palm kernel oil ester by incorporating Al2O3 and TiO2 nanoparticles. The dispersion of nanoparticles in the fluid was found to increase the breakdown voltage and decrease the dielectric loss of the nanofluid sample, showing improved performance compared to the base alkyl ester.
MATERIALS CHEMISTRY AND PHYSICS
(2021)
Article
Computer Science, Information Systems
Mridula, Nagaraju Guvvala, R. Sarathi, R. Vinu
Summary: This paper investigates the effect of adding micro-porous zeolite to the thermally aged synthetic ester oil to evaluate its electrical performance under the influence of external local magnetic field variation. The results show that the Corona Inception Voltage and Particle Levitation Voltage decrease with ageing in the presence of magnetic field. Under a certain magnetic flux density, the detected UHF signal is dominant at low frequencies. Furthermore, the addition of zeolite in the synthetic ester liquid tends to improve the electrical performance of the aged oil.
Article
Materials Science, Composites
Lihua Zhao, Weiqing Wu, Lichuan Jia, Zongxi Zhang, Zhong Wang, Xiaolong Huang, Wenjun Ning, Junwen Ren
Summary: This study introduces a new strategy to prepare dielectric paper by combining one-dimensional aramid nanofiber with two-dimensional fluorinated graphene. The obtained paper shows low dielectric constant, high breakdown strength, and excellent mechanical properties, making it promising for applications in high-temperature electronics.
COMPOSITE INTERFACES
(2022)
Article
Chemistry, Applied
Yi Ning, Dian-sen Li, Lei Jiang
Summary: This study presents a facile and solvent-free synthesis of a renewable toughening agent EGFD, which was successfully used to modify bismaleimide monomer to synthesize toughened EGFD/BMI resin. The cured resin exhibits excellent toughness, deformation reversibility, thermostability, and dielectric properties.
REACTIVE & FUNCTIONAL POLYMERS
(2022)
Article
Polymer Science
Wenchao Zhang, Kuo Zhao, Feng Guan, Jinghua Yin, Yu Feng, Jialong Li, Yanpeng Li
Summary: By adding SiO2 nanoparticles, this study achieved a high dielectric constant and long corona aging lifetime for FPE-based composite films, while maintaining the molecular chain structure of FPE and increasing the thickness of the filler-matrix interface. The dielectric constant of the composites increased significantly, and the corona resistance lifetime improved by about 12 times compared to pure FPE matrix.
Article
Polymer Science
Yan Yang, Jielin Ma, Malvern Yap, Qi Wang, Wen Kwang Chern, Yi Shyh Eddy Foo, Zhong Chen
Summary: In this study, the hygrothermal aging of an epoxy composite insulation material was conducted at different temperatures and relative humidity levels. Electrical properties, including volume resistivity, electrical permittivity, dielectric loss, and breakdown strength, were measured. It was found that the IEC 60216 standard, which uses breakdown strength as a criterion, is inadequate for estimating the lifetime of the material due to the minimal changes in breakdown strength during hygrothermal aging. However, significant increases in dielectric loss correlated well with the mechanical strength-based lifetime prediction, leading to the proposal of a new criterion for determining the end of life of the material.
Article
Engineering, Electrical & Electronic
Amr M. Abd-Elhady, Alyaa A. Nassar, Mohamed A. Izzularab, Mohamed E. Ibrahim
Summary: The main focus of this study is to investigate the thermal aging of oil filled transformers, with particular emphasis on the insulation system. The results show that the performance of the oil/paper insulation system is significantly affected by factors such as epoxy coating and nanofillers.
ELECTRIC POWER SYSTEMS RESEARCH
(2022)
Article
Energy & Fuels
Gottapu Tirupati Naidu, Ungarala Mohan Rao, Sudabattula Suresh
Summary: This paper investigates the diffusion behavior of mineral oil and ester fluids, and their influence on paper breakdown voltage. The results show that ester fluids exhibit superior performance in increasing paper dielectric strength and diffusion behavior compared to mineral insulating oils.
Article
Computer Science, Information Systems
S. K. Amizhtan, A. J. Amalanathan, R. Sarathi, R. Vinu
Summary: This study investigates the effect of sulfur compounds in mineral oil on the aging of pressboard material. The results show that a higher concentration of DBDS reduces the surface discharge inception voltage (SDIV) of aged pressboard specimens, while the addition of Ag2S does not have the same effect. Tensile testing and Digital Image Correlation (DIC) technique were used to analyze the mechanical strength and strain percentage of the aged pressboard specimens. Laser induced breakdown spectroscopy (LIBS) analysis identified the elements responsible for thermal aging, and Principal Component Analysis (PCA) was used to classify the degradation of pressboard due to the diffusion of copper and silver sulfide from the mineral oil.
Article
Materials Science, Characterization & Testing
Simone Vincenzo Suraci, Davide Fabiani, Sebastien Roland, Xavier Colin
Summary: This article investigates the aging behavior of nuclear-grade low voltage cables, finding that aging is deeply influenced by additives (e.g. antioxidants) and dielectric spectroscopy is appropriate for non-destructive condition monitoring of cables. Antioxidants delay oxidation process and dielectric response evolution is associated with variations in considered chemical and mechanical properties, allowing the derivation of correlation master curves.
Article
Computer Science, Information Systems
Jaafar Adnan, Mohd Taufiq Ishak, Nur S. S. Suhaimi, Nurul 'I. Hashim, Khairol A. A. Ahmad, Fakroul R. R. Hashim, Rushdan Ibrahim
Summary: The availability of raw materials for fiber production is decreasing as demand increases. This study investigates the use of empty fruit bunch (EFB) as a substitute for insulating paper. EFB shows comparable performance to conventional insulating paper, making it a potentially valuable alternative.
Article
Polymer Science
Liliana Rosu, Cristian-Dragos Varganici, Dan Rosu, Stefan Oprea
Summary: The study demonstrates that poly(ester urethane) elastomers designed as damping materials for railways maintain good mechanical properties after 200 hours of thermal aging at elevated temperatures, but significant changes in thermo-mechanical and optical properties occur with increasing time and temperature.