Detection and localization of disk-to-disk short circuits in transformer HV windings using an improved model

Abstract

Summary This paper presents a new improved detailed model for transformer windings. This model accurately represents the transient behaviour of transformer winding better than does the conventional detailed model. The dominant resonance frequencies can be identified using the conventional model; however, nondominant resonance could not be detected. The proposed model can detect both dominant and nondominant resonance frequencies. Frequency response analysis was applied to a 20/0.4 kV 1600 kVA transformer. The simulation results obtained by the conventional and proposed models were compared with the measurement results. The results show the ability of the improved version to model dominant and nondominant resonance. A heuristic method is also proposed to overcome the problem of estimating parameters in large-scale models.