Global sensitivity and criterion performance analysis of transformer leakage inductance to winding deformation

At present, some methods have been put forward to detect the winding deformation using the leakage inductance(L_k) of the transformer, but the research on the inherent law of L_k and deformations is not enough. In this paper, a calculation model of L_k based on response surface(RS) method is proposed. In an example of a real transformer, the results of RS model are basically coincident with its actual variation of leakage inductance. Combining RS model and Sobol' global sensitivity analysis method based on Monte Carlo algorithm, the global sensitivities of L_k to different deformations are analyzed The results show that the sensitivities are obviously dissimilar, and the change of L_k will be more obvious under the condition of multiple deformations. At last, In the case of a fixed threshold, the matching between deformation criterion and the transformer operating capacity is analyzed. Result indicates the action of the deformation criterion does not exactly match the transformer operating capacity.