[摘要]:A new method for the on-line monitoring of transformer winding radial deformations using ultra-wideband sensors is presented in this paper. A wideband signal is sent to a simplified model of the transformer winding. The measurements of received signals from the model winding demonstrate the sensitivity of the proposed technique to the winding radial deformation. It is shown that the deformation volume can be estimated using a proposed index. Also, the amount of the radial deformation is estimated by using a regression tree based on features extracted by the wavelet transform.