The STFT Applied to Inter-Harmonics Analysis in Transformer

This paper introduces that the Short Time Fourier Transform (STFT) could be applied to analyze the time-frequency characteristics of inter-harmonics in transformer. Compared with the traditional Fourier Transform, the STFT could acquire more clear result, and offers theoretical basis for inter-harmonic detection. The STFT is used to analyze the inter-harmonics by selecting proper window slides function in Matlab which can obtain more precise resolution for the time-frequency characteristics. This method is useful to eliminate the inter-harmonics in transformer. It is helpful to improve the quality of power.