Investigation of saturation moisture in the PD behavior in the biodegradable ester oil

Maharana, Mrutyunjay; Hamasuna, Kyouhei; Kozako, Masahiro; Hikita, Masayuki; Tsuchie, Motoo; Wu, Kai

doi:10.23919/cmd54214.2022.9991312

Cited by 3 publications

(3 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the other hand, there has been few report on the temperature dependence of AC BDV in ester oil on relative moisture content (RMC) to saturation moisture content (SMC). In a previous report, the authors showed that increasing the temperature of ester oil (FR3, PFAE) increased moisture content (MC) in the oil, resulting in a lower BDV [7]. This paper presents the effect of the moisture content on the insulation properties of three kinds of ester oils with controlled moisture content at 30 %, 40 %, and 50 % RMC at different temperatures.…”

Section: Introductionmentioning

confidence: 88%

Effect of Moisture Content on Temperature Characteristics of Dielectric Breakdown Strength of Biodegradable Ester Oils

Okamoto,

Okumura,

Hamasuna

et al. 2023

2023 IEEE 22nd International Conference on Dielectric Liquids (ICDL)

View full text Add to dashboard Cite

The authors showed in previous report that the relative moisture content of biodegradable ester oil increases with increasing temperature, which affects the AC breakdown voltage (BDV). This paper presents the dependence of BDV on moisture content and temperature under conditions of high moisture content in biodegradable ester oil (EO). AC BDV of the three biodegradable ester oils, PFAE (monoester), FR3 (triester), and MIDEL (tetra-ester), with different ester linkages, was measured at different oil temperatures and relative water contents using sphere electrodes. Results showed that BDV decreased with increasing moisture content (MC) in all kinds of the ester oils. The BDV of PFAE and FR3 decreased from room temperature to 50 °C, but then increased in the temperature range from 50 °C to 80 °C. The decrease and increase in insulation properties are attributed to an increase in water content in the oil and to the viscosity decrease resulting in suppression of streamer discharge propagation, respectively. On the other hand, BDV of tetra-ester continued to decrease with increasing temperature. This result can be attributed to the larger number of ester bonds, unlike monoesters and tri-ester. The ester linkages in the material are a weak point in the insulating properties, which can easily lead to a decrease in BDV at all the measuring temperatures.

show abstract

Section: Introductionmentioning

confidence: 88%

Effect of Moisture Content on Temperature Characteristics of Dielectric Breakdown Strength of Biodegradable Ester Oils

Okamoto,

Okumura,

Hamasuna

et al. 2023

2023 IEEE 22nd International Conference on Dielectric Liquids (ICDL)

View full text Add to dashboard Cite

show abstract

“…In general, the electrons and hole carriers in the insulating oil in practical applications are more likely to be injected by electrodes and be trapped by the oil through contact with the conductor, forming a space charge of electrons (holes). But the ions’ involvements are more complex, and their source has critical chemical reactions involving aging and PD . In this study, key analysis is carried out on the conductivity of electrons and holes, but carrier generation process are not taken into consideration.…”

Section: Introductionmentioning

confidence: 99%

“…But the ions' involvements are more complex, and their source has critical chemical reactions involving aging and PD. 10 In this study, key analysis is carried out on the conductivity of electrons and holes, but carrier generation process are not taken into consideration.…”

Section: ■ Introductionmentioning

confidence: 99%

Calculation of Charge Transport Phenomena and Mobility Analysis in the Insulating Oil Using First Principle and Marcus Theory

Chen,

Liu,

Maharana

et al. 2024

J. Phys. Chem. B

Self Cite

View full text Add to dashboard Cite

Oil-paper insulation is widely used as a reliable composite insulation system in power transformers. The dielectric property of oil insulation plays an important role in the reliable operation of power equipment. To recognize the charge transfer process in composite insulation, the mobility of the charge in aged insulating oil is studied. However, few studies have been conducted on the microscopic mechanism of charge transport phenomena at the molecular level. In this research, we have studied the molecular electronic structure and the distribution of holes and electrons in the insulating oil by first-principles calculation. By combining with Marcus theory, the corresponding electron coupling energy, reorganization energy, and free energy are obtained. The corresponding charge hopping model is chosen by the parameter relation, and the hopping rate is calculated. At last, the mobility of holes and electrons in insulating oil within the insulation is simulated by the Monte Carlo method. Other possible charge migration methods are also studied and discussed for the comparison. It is observed that the transfer integral of electrons is 2 orders of magnitude larger than that of holes, which is mostly due to the localization of lowest unoccupied molecular orbitals (LUMO). The hole and charge transfers accord with Marcus hopping, the adiabatic charge transfer model, and the charge hopping rate is obtained. The actual free energy action under an external electric field is obtained by calculating polarizability and permittivity. Monte Carlo simulation is used to obtain the charge transfer image and mobility under an actual electric field. Possible types of traps and mobility of ions and clusters in the insulating oil are also studied.

show abstract

Effect of Moisture Content on Temperature Dependence of Partial Discharge Characteristics of Biodegradable Ester Oil

Okamoto,

Okumura,

Tsuchie

et al. 2023

2023 International Symposium on Electrical Insulating Materials (ISEIM)

View full text Add to dashboard Cite

Investigation of saturation moisture in the PD behavior in the biodegradable ester oil

Cited by 3 publications

References 6 publications

Effect of Moisture Content on Temperature Characteristics of Dielectric Breakdown Strength of Biodegradable Ester Oils

Effect of Moisture Content on Temperature Characteristics of Dielectric Breakdown Strength of Biodegradable Ester Oils

Calculation of Charge Transport Phenomena and Mobility Analysis in the Insulating Oil Using First Principle and Marcus Theory

Effect of Moisture Content on Temperature Dependence of Partial Discharge Characteristics of Biodegradable Ester Oil

Contact Info

Product

Resources

About