Temperature Field Simulation Analysis of Distribution Transformers Based on Fluid-Temperature Field Coupling

With the introduction of large-scale new energy sources into the grid, a threat is posed to the entire power system. Especially on the distribution network side, the increased penetration of photovoltaic grid connection has led to a prolonged overload of distribution transformers, which can accelerate the internal insulation ageing of transformers. Therefore, in this paper, a two-dimensional symmetrical model of distribution transformer with fluid-temperature field is established by finite element simulation. In addition, the temperature distribution inside the transformer under different load rates is analyzed, and the oil circulation speed inside the transformer when the temperature limit is exceeded is studied. It is concluded that when the load rate exceeds 1.2, the internal oil circulation speed shall not be less than 0.08m/s; when the load rate exceeds 1.5, the internal oil circulation speed shall not be less than 0.12m/s.