N2 - A fault diagnostics system of three-phase induction motors was implemented. The implemented system was based on acoustic signals of three-phase induction motors. A feature extraction step was performed using SMOFS-20-EXPANDED (shortened method of frequencies selection-20-Expanded). A classification step was performed using 3 classifiers: LDA (Linear Discriminant Analysis), NBC (Naive Bayes Classifier), CT (Classification Tree). An analysis was carried out for incipient states of three-phase induction motors measured under laboratory conditions. The author measured and analysed the following states of motors: healthy motor, motor with one faulty rotor bar, motor with two faulty rotor bars, motor with faulty ring of squirrel-cage. Measured and analysed states were caused by natural degradation of parts of the machine. The efficiency of recognition of the analysed states was good. The proposed method of fault diagnostics can find application in protection of three-phase induction motors. L1 - http://journals.pan.pl/Content/102713/PDF/aoa-2016-0049.pdf L2 - http://journals.pan.pl/Content/102713 PY - 2016 IS - No 3 EP - 515 DO - 10.1515/aoa-2016-0049 KW - induction motor KW - machine KW - acoustic signal KW - acoustic emission KW - fault diagnostics A1 - Glowacz, Adam PB - Polish Academy of Sciences, Institute of Fundamental Technological Research, Committee on Acoustics VL - vol. 41 DA - 2016 T1 - Diagnostics of Rotor Damages of Three-Phase Induction Motors Using Acoustic Signals and SMOFS-20-EXPANDED SP - 507 UR - http://journals.pan.pl/dlibra/publication/edition/102713 T2 - Archives of Acoustics