Application of Variational Mode Decomposition and Multiscale Permutation Entropy in Rolling Bearing Failure Analysis

Table 2

Comparison of different thresholds (K = 3).

	Center frequency (Hz)
Normal condition	108	1046	2101
Inner ring fault	684	2753	3559
Roller fault	677	2918	3372
Outer ring fault	779	2836	3422