Joint Amplitude and Frequency Demodulation Analysis Based on Variational Mode Decomposition for Multifault Diagnosis of a Multistage Reducer

Table 3

Rotation frequencies of the gears at each stage and characteristic frequencies of the faulty gears.

Parameter	First-stage planetary gear				Second-stage spur gear			Third-stage spur gear
	Sun gear	Planet gear	Planet carrier	Meshing frequency	Driving gear	Driven gear	Meshing frequency	Driving gear	Driven gear	Meshing frequency
Rotation frequency	29.63	18.02	6.48	648.59	6.48	1.88	188.09	1.88	0.75	67.71
Characteristic frequency of local fault	92.64	18.02	—	—	6.48	1.88	—	1.88	0.75	—
		36.04
Characteristic frequency of distributed fault	23.16	18.02	—	—	188.09	188.09	—	67.71	67.71	—