Fault Diagnosis of a Hydraulic Pump Based on the CEEMD-STFT Time-Frequency Entropy Method and Multiclass SVM Classifier

Table 1

Six-dimensional fault features.

Fault pattern	No.	Feature 1	Feature 2	Feature 3	Feature 4	Feature 5	Feature 6
Normal	1	4.9681	3.9921	4.0155	3.6082	3.2670	2.6576
	2	4.9732	3.9936	4.0145	3.6031	3.2395	2.6541
	⋯
	20	4.7565	3.9406	4.1075	3.6274	3.3763	2.6567
Rotor wear	21	3.8933	4.2478	3.5822	3.7066	3.2937	2.5966
	22	3.8923	4.1903	3.5846	3.7407	3.2990	2.5675
	⋯
	40	3.8991	3.9456	3.5417	3.6743	3.3190	2.5426
Swash plate wear	41	4.1123	3.4824	3.4975	3.6294	3.2926	2.5332
	42	4.1285	3.4886	3.5151	3.6196	3.3310	2.5820
	⋯
	60	4.1782	3.4949	3.5132	3.5932	3.3496	2.6182