In order to solve the problem of increasing the size and weight of low-frequency power transformer

a lightweight design method of low-frequency transformer based on high-temperature insulation system is proposed. The breakdown characteristics of mineral oil

synthetic ester

and synthetic ester oil paper insulation system under low frequency and power frequency conditions were measured through experiments

and the influence of frequency change on the breakdown characteristics of insulation materials was explored

which laid the foundation for the optimization design. By combining the material properties with multi-objective genetic algorithm

a weight size loss comprehensive optimization model is constructed. A 330 MVA/220 kV transformer is taken as an example

and the effectiveness of the optimization scheme is analyzed by comparing with the same type of low-frequency transformer used in low-frequency transmission projects. After optimization

the total weight is reduced by 12.7%

and the tank size is reduced by 12.05%

which is not more than 1.5 times of the weight and size of the same type of power frequency transformer. The optimization results are verified by temperature field and electric field simulation. The life cycle cost analysis shows that the maintenance cost of low-frequency transformer with high-temperature insulation system is lower

and the life cycle cost is reduced by 7.36% compared with the traditional mineral oil scheme. The research results can provide an optimization scheme for the lightweight design of low-frequency transformer.