Time frequency Analysis of Track Irregularity Based on Improved Empirical Mode Decomposition Method

Abstract:

The end effect is a fatal flaw of empirical mode decomposition (EMD). Based on the principle of end effect and the present study situation, a method combining the mirror extension with the gray neural network is proposed to extend the data. Analysis of the simulated signal and the actual track irregularity signal shows that the proposed method restrains the end effect effectively．The track irregularity signal is studied with the improved EMD method, which collected by track recording vehicles from Beijing—Guangzhou Railway and Wuhan—Guangzhou passenger railway. The statistic and analysis result indicates that there are relatively serious short wave and long wave track irregularity in Beijing—Guangzhou Railway, and the irregularity wavelength characteristic of Wuhan—Guangzhou passenger railway is the medium wave and long wave. Analysis of track irregularity with improved EMD is a new technical method for guaranteeing the safe running of railway.

Key words:track irregularity; empirical mode decomposition; end effect; timefrequency analysis