Study on THz Spectral Characteristics of Natural Ester Insulation Oil

Natural ester not only has the advantages of excellent biodegradability and environmental protection, but also has a higher fire rating and anti-overload ability. Therefore, it is an excellent insulation liquid material. In this paper, terahertz time-domain spectroscopy (THz-TDS) is used to study the characteristics of natural ester (FR3) insulation oil in THz range. The results show that: the FR3 insulation oil has an average refractive index of 1.533 in the range of 0.1-1.80THz, and there are two absorption peaks at 1.30THz and 1.50THz. The average values of the real part of complex permittivity and dielectric loss of FR3 in 0.1-1.80Thz are 2.353 and 0.002, and there is relaxation behavior in 1.30Thz and 1.50Thz. This article lays a foundation for studying the THz properties of FR3 insulation oil and has important practical significance.