Diagnosis of rotor asymmetries in induction motors based on the transient extraction of fault components using filtering techniques

[EN] The aim of this paper is to present and validate a methodology for diagnosing rotor asymmetries in cage motors, based on the analysis of the stator startup current. The method consists of the extraction of a harmonic component introduced by this fault - the left sideband component - from the stator startup current. Two alternative techniques developed by different research groups are proposed for the transient extraction of this component; the digital low-pass filtering (DLPF) and the discrete wavelet transform (DWT). Both approaches are applied to three different industrial motors ranging from 1.1 to 450kW. A detailed explanation of the physical basis of the method and comments related to the application scope of the approach are also given. The results show the robustness of both approaches for the reliable diagnosis of the fault and suggest a clear potentiality for extending the methodology to the detection of other types of faults introducing components dependant on the slip. (C) 2009 Elsevier B.V. All rights reserved.This work was supported by the Spanish “Ministerio de Educación y Ciencia”, in the framework of the “Programa Nacional de proyectos de Investigación Fundamental”, project reference DPI2008-06583/DPI. The authors also thank ‘Vicerrectorado de Investigación, Desarrollo e Innovación of Universidad Politécnica de Valencia’ for financing a part of this research through the program ‘Programa de Apoyo a la Investigación y Desarrollo’ (PAID-06-07).Riera-Guasp, M.; Antonino-Daviu, J.; Rusek, J.; Roger-Folch, J. (2009). Diagnosis of rotor asymmetries in induction motors based on the transient extraction of fault components using filtering techniques. Electric Power Systems Research. 79(8):1181-1191. doi:10.1016/j.epsr.2009.02.009S1181119179