变压器绕组热点温度是制约其带负载能力和运行寿命的决定性因素。以一台S20-M-630 kVA/10 kV油浸式配电变压器为研究对象，建立了包含外壳散热片在内的三维电磁-温度-流体耦合模型。针对其绕组内部结构复杂、流固边界层网格质量差、计算效率低下等问题，提出了绕组参数等效方法与结合映射剖分和自由剖分的混合网格剖分技术。该方法不仅显著提升了绕组热点温度的计算精度，还优化了流固边界层的网格质量，大幅提高了计算效率。结果表明：绕组参数等效方法能有效反映变压器实际工作中绕组的温度分布，混合剖分相比与全自由剖分达到相同结果下的整体三维网格数量和仿真时间分别减少了73.60%、82.50%，绕组热点温度仿真值与试验值相对误差不超过1%。

Load capacity and operating life are governed by the hot spot temperature of the transformer windings. A three-dimensional electromagnetic-temperature-fluid coupling model including the shell heat sink is established with an S20-M-630 kVA/10 kV oil-immersed distribution transformer as the research object. Aiming at the problems of complex internal structure of the winding, poor mesh quality of the fluid-solid boundary layer, and low computational efficiency, a winding parameter equivalence method and a hybrid mesh profiling technique combining mapping profilings and free profilings are proposed. The method not only significantly improves the accuracy of the calculation of the winding hot-spot temperature, but also optimises the mesh quality of the fluid-solid boundary layer, which significantly improves the calculation efficiency. The results show that in actual transformer operation, the winding temperature distribution can be effectively reflected by the winding parameter equivalence method, and compared with free profiling, hybrid profiling reduces the overall number of 3D meshes and simulation time by 73.60% and 82.50%. The relative error between the simulated and experimental values of the winding hot-spot temperature shall not exceed 1%.