Improvement and implementation of inverse EMD algorithm based on second order envelope

On the basis of analysing the classic empirical mode decomposition (EMD) method and the inverse EMD method in which the high-order extreme value point is used in reverse screening, a method based on second order envelope inverse EMD was proposed. The method integrates the good properties of the classic EMD and inverse EMD. Making use of the first and second order envelope and introducing certain conditions in the screening process, the mean value of an optimal envelope was chosen for screening. The experimental results show that the method is suitable for being applied to decompose multi-component signals with low frequency difference between components. It can reduce the error of high frequency components, effectively decrease the estimation error and restrain the excess IMF components. The EMD decomposition effect will be better when the optimal envelope is adopted in screening. © 2017 Chinese Vibration Engineering Society. All rights reserved.