Engineering Calculation Method Research On Eddy Current Loss And Temperature Distribution Of Transformer Winding

Capacity of a transformer increasing with the enlargement of power system capability, research on eddy current losses and overheating caused by leakage magnetic field is very important. The numerical model is set up for both foil-type transformer and Oil-immersed transformer in this paper. Then in the case of steady-state operation,distribution of the stray field, winding eddy current loss are calculated by using FEM. The corresponding distribution parameters and some conclusions having engineering value are obtained, and provides a reliable calculate method of the transformer load loss .Distribution of the eddy current loss can be the base of calculation of temperature distribution in transformer windings.The comparison between the calculation and the measurement shows that the calculating method and result of load loss meet the design requirement of products.At present, in oil immersed transformers natural oil circulation is used at about 80%. A direct reslut of adopting natural oil circulation is to increase the temperature difference between copper and oil. So the heat elimination becomes more serious. Based on the theory of heating, cooling and analysis of winding eddy loss distribution using finite element method for oil-immersed transformer, calculation method of temperature distribution in transformer windings is determined. Based on calculate the eddy current loss of the split unit by using MF2D special software, the algorithm is added to the project, then debug the computer program. Validation of winding temperature distribution is confirmed by comparing the measured result with the calculated value of the product. Simple and effective method is given for the calculation of temperature rise distribution and prevention of local overheating of oil-immersed transformer reasonably.