Papers by Keyword: TT-Transform

Abstract: Towards the problem of power quality disturbance detecting and localization in the power system, this paper proposed a new method based on improved TT-transform. Amplitude’s mutation in maximum element sequence of the TT- module matrix’s row is detected to locate beginning and ending time of power quality disturbances. This method can not only detect single power quality disturbance, but also detect composite disturbance accurately. The simulation results show that the method proposed can accurately detect the common power quality disturbance signal.

Abstract: Machine vibration signal has been used in fault detection and diagnosis. Modulation and non-stationarity existing in the signal generated by a faulty gearbox present challenges to effective fault detection. Hilbert transform has the ability to address the modulation issue. This paper outlines a novel fault detection method called Hilbert & TT-transform (HTT-transform) which combines Hilbert transform and TT-transform obtained from the inverse Fourier transform of the S-transform. The principle of the proposed method is to analyze the modulating signal created by a faulty gear using a time-time representation. The method has the advantage of providing a new way of localizing the time features of the modulating signal around a particular point on the time axis through scaled windows. It is verified with simulated signals and real gearbox vibration signals. The results obtained by CWT, S-transform, TT- transform, and HTT-transform are compared. They show that utilizing the proposed method can improve the effectiveness of gearbox fault detection.