Frequency-Domain Based Fault Detection: Application of Short-Time Fourier Transform

This chapter introduces the frequency-domain based transient analysis of the dc fault currents. Short-Time Fourier Transform (STFT) based fault analysis has been proposed as a frequency domain method for transient state detection in dc networks. This chapter describes in detail the operation of STFT based transient detection with the support of analytical formulations. Application of STFT based transient state detection with sensitivity analysis has been performed for the point-to-point and multi-terminal high-voltage dc transmission system. The results show that STFT method can be effectively be used for fault detection with substantial accuracy.