*Article* **Multiple Fault Detection in Induction Motors through Homogeneity and Kurtosis Computation**

**Ana L. Martinez-Herrera, Edna R. Ferrucho-Alvarez, Luis M. Ledesma-Carrillo, Ruth I. Mata-Chavez, Misael Lopez-Ramirez and Eduardo Cabal-Yepez \***

> Multidisciplinary Studies Department, Engineering Division, Campus Irapuato-Salamanca, University of Guanajuato, Guanajuato 38944, Mexico; martinez.al@ugto.mx (A.L.M.-H.); er.ferruchoalvaez@ugto.mx (E.R.F.-A.); lm.ledesma@ugto.mx (L.M.L.-C.); ruth@ugto.mx (R.I.M.-C.); lopez.misael@ugto.mx (M.L.-R.) **\*** Correspondence: educabal@ugto.mx; Tel.: +52-445-458-9040

> **Abstract:** In the last few years, induction motor fault detection has provoked great interest among researchers because it is a fundamental element of the electric-power industry, manufacturing enterprise, and services. Hence, considerable efforts have been carried out on developing reliable, low-cost procedures for fault diagnosis in induction motors (IM) since the early detection of any failure may prevent the machine from suffering a catastrophic damage. Therefore, many methodologies based on the IM startup transient current analysis have been proposed whose major disadvantages are the high mathematical complexity and demanding computational cost for their development. In this study, a straightforward procedure was introduced for identifying and classifying faults in IM. The proposed approach is based on the analysis of the startup transient current signal through the current signal homogeneity and the fourth central moment (kurtosis) analysis. These features are used for training a feed-forward, backpropagation artificial neural network used as a classifier. From experimentally obtained results, it was demonstrated that the brought-in scheme attained high certainty in recognizing and discriminating among five induction motor conditions, i.e., a motor in good physical condition (HLT), a motor with one broken rotor bar (1BRB), a motor with two broken rotor bars (2BRB), a motor with damage on the bearing outer race (BRN), and a motor with an unbalanced mechanical load (UNB).

> **Keywords:** artificial neural network; fourth central moment; homogeneity analysis; induction motors; mechanical unbalance; one broken rotor bar; outer-race bearing fault; startup transient current; two broken rotor bars
