The Research On The Temperature Field Of Dry-power Transformer

The design of temperature rise of dry type transformer is an important and complicated problem in the design of power transformer. This is mainly because most of the faults of dry-type transformers are directly or indirectly caused by temperature anomalies. When the internal temperature is too high, it may cause insulation aging and affect its service life,more likely to cause a vicious explosion.Therefore, it is of great significance to analyze and calculate the temperature field of dry-type transformer.In this thesis, the temperature field of dry-type transformer is analyzed in detail by means of simulation and experiment. Firstly, analyzes the generation and dissipation of the transformer internal heat source, combined with heat transfer and fluid mechanics, each part of the transformer numerical analysis provides the theoretical calculation equation. Secondly, according to the actual structure parameters of the transformer, drawing two-dimensional numerical simulation analysis model,determine the internal heat source and boundary conditions,and reasonable grid dividing the model. In this thesis, the fluid solid coupling field is analyzed and calculated based on the actual operation of the transformer using Fluent fluid dynamics software. The heat transfer in natural conditions, analysis of the temperature field distribution of high and low voltage winding and core respectively,and the temperature distribution in the axial and radial position, and find out the internal hot the damage caused by hot spot temperature rise is analyzed, and some measures to improve the temperature rise are put forward. Thirdly, the SCB10 series transformer for the field test, the simulation results compared with the test results, the conclusion was applied to the design of the temperature rise. Finally, the field test of SCB10 series transformer, the influence of the size of the airway temperature rise at the same time,the temperature rise of the theoretical calculation formula of the coefficient of correction,the temperature calculation results further meet the needs of the project.In this thesis,the temperature field is analyzed and the temperature rise is calculated by using the common lOkV class SCB10-1250/10 epoxy cast dry-type transformer. According to the simulation principle and the control equation, the simulation of transformer internal temperature field by using Fluent finite element analysis software, and through a lot of experiments on the transformer temperature the theoretical calculation formula of correction. Field test with the SCB10 series transformer as a testing transformer. The experimental data and simulation data can provide technical reference for designers.