Vegetable insulating oil

as an insulating medium

is generally recognized as a good alternative to mineral insulating oil due to its excellent environmental friendliness

fire resistance and renewability. However

its poor cold flow characteristics such as high viscosity and high pour point enable the low-temperature operation reliability of vegetable insulating oil in transformer to be not high

which has become a bottleneck restricting its wide application. Therefore

in this paper

we first systematically sort out the research results on the cold flow characteristics of vegetable insulating oils

focus on the microscopic molecular structure of vegetable insulating oils

and discuss the relationship between the fatty acid species

carbon chain length

degree of unsaturation

and molecular geometric configurations of vegetable insulating oils and their cold flow characteristics. Then

the improvement methods to enhance the cold flow characteristics of vegetable insulating oils are discussed

the advantages and disadvantages of different improvement methods are summarized

and the subsequent research dynamics and development prospects of the cold flow characteristics of vegetable insulating oils for transformers are envisioned. This research summary will provide reference for the application of vegetable insulating oils in improving cold flow characteristics and transformer insulation systems.