Fault classification of broken rotor bars in induction motors based on envelope current analysis

In this article a method for the detection of one, two, and three broken bars in induction motors under full load condition is presented. The proposed methodo is based on current envelope analysis. The information obtained from the envelope current is valuable in manifesting and validating the presence of a broken bar fault, since it contains important information about the existence of a fault as well as its severity. The proposed method mainly focuses on the case of steady-state operation under full load. In the established fault diagnosis scheme six features are extracted from the envelope of the current and after the application of a Principal Component Analysis stage are fed to a classifier to perform the diagnosis. Three different classifiers, a linear, a quadratic and a nearest neighbour are investigated for the final stage of the diagnosis. The presented approach manifested promising results using experimental data.