Study on wavelet analysis and its application to numerical protection for large synchronous generator

The definition, applied characteristics as well as fast algorithm of wavelet transform (WT) are introduced in this paper. The designation of WT based high pass (HP), band pass (BP) filters and their applications to numerical protection for large generator against stator internal faults as well as stator earth fault are also presented. Research results based on EMTP simulation and laboratory micromachine experiments show that WT can effectively improve the sensitivity and selectivity of traditional numerical protection principles and criteria