Internal Fault Discrimination in Power Transformers Using Curvelet Transform

This paper presents the analysis and development of a new digital differential protection scheme for three phase power transformers. The proposed scheme extracts the high frequency information hidden in the differential as well as the fault currents to identify internal faults. The commonly used signal processing tool, Wavelet Transform which has an impressive reputation in this field fails to represent objects with highly anisotropic elements such as lines or edges efficiently due to the limitations in directional and scaling elements. Proposed scheme applies curvelet transform to the differential current to extract the required information and identify the faults. Extensive simulation using MATLAB Simulink has been done to validate the method and the results are validated by comparing with other schemes.