Journal
IET SCIENCE MEASUREMENT & TECHNOLOGY
Volume 13, Issue 8, Pages 1194-1202Publisher
INST ENGINEERING TECHNOLOGY-IET
DOI: 10.1049/iet-smt.2019.0117
Keywords
surface discharges; permittivity; differential scanning calorimetry; tensile strength; tensile testing; ageing; harmonic distortion; transformer oil; plasma temperature; impregnated insulation; dielectric relaxation; electrical conductivity; natural ester oil impregnated cellulosic pressboard; natural ester oil impregnated pressboard material; surface discharge inception voltage; harmonic AC voltages; DC voltages; natural ester OIP; ageing time; thermally aged OIP material; thermally aged specimens; cellulosic material; aged material; phase-resolved partial discharge; harmonic distortions; surface potential measurement; ripple content; ageing temperature; high-density charge traps; laser-induced breakdown spectroscopy; plasma temperature; differential scanning calorimetry; mechanical strength; tensile test; dielectric response spectroscopy; permittivity; tan(delta); DC conductivity; relaxation time; activation energy
Categories
Funding
- CPRI, Bangalore
Ask authors/readers for more resources
An attempt is made to understand the effect of thermal ageing on natural ester oil impregnated pressboard material. Surface discharge inception voltage of natural ester oil impregnated pressboard material is reduced drastically under AC, harmonic AC voltages and with DC voltages with high ripple content. Phase-resolved partial discharge studies show an increase in the number of discharges for natural ester oil impregnated pressboard (OIP) aged at higher temperature, under AC and harmonic AC voltages with different total harmonic distortions. Surface potential measurement study complies with results obtained by surface discharge inception voltage. It indicates the presence of high-density charge traps evolved as a function of ageing time and temperature. Laser-induced breakdown spectroscopy analysis is carried out to understand the characteristic variation with thermally aged OIP material. A decrease in plasma temperature is observed for sample aged at higher temperature. Differential scanning calorimetric studies indicate reduction in peak temperature with thermally aged specimens. Ageing observed to affect mechanical strength of the cellulosic material, as indicated by tensile test. Dielectric response spectroscopy study indicates that with an increase in thermal ageing, the permittivity, tan(delta), DC conductivity and relaxation time have increased. A reduction in activation energy of the aged material is observed, which indicates the status of the OIP material.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available