Abstract：Aiming at the problems of the end effects and the overshoot and undershoot during envelope fitting in empirical mode decomposition, a new method is proposed by using piecewise Hermite interpolation to solve the overshoot and undershoot problems.Combining with the extreme point extension window function, the end effects problem is solved based on slope re-optimization.The results are that the envelope fitting is optimized, the IMFs are more accurate, the Hilbert spectrum and boundary spectrum are also more accurate by Hilbert transform and finally the quality of EMD algorithm is improved.The simulations and the rolling bearing fault diagnosis case show that the new method has a good effect and can effectively diagnose rotating machinery faults.
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2016, Vol. 37 
