Analysis and diagnosis of the different defects of asynchronous machines by vibration analysis Abdelkader BENBOUAZA Engineer Research Department Mathematic and Mechanic National School of Applied Sciences Oujda, MOROCCO a.benbouaza@gmail.com Bachir ELKIHEL Prof. and head of department Department Mathematic and Mechanic National School of Applied Sciences Oujda, MOROCCO belkihel@ensa.ump.ma Fabienne DELAUNOIS Prof. and head of department Department of Metallurgy Mons University fabienne.delaunois@umons.ac.be Abstract— The electric machines and particularly the asynchronous machines act an important role nowadays in all industrial applications. To assure the availability and the safety of working of these is a fundamental job. It is therefore necessary to develop the systems permitting to supervise and to diagnose the state of health of these devices. This article has for object to determine the different anomalies that can harm the good working of an electric motor. Keywords-asynchronous machines; vibration analysis; Conditional Maintenance; spectral analysis; envelope analysis. I. INTRODUCTION Although the asynchronous machine is reputed robust, it presents sometimes different types off defects. These defects are declared in the different parts off the machine starting with the connection off the stator phases and ending with the mechanical coupling off the rotor to the load. These failures can be predicted or untimely, mechanical, electrical or magnetic, and their reasons are varied. A statistical study done on[1] on the asynchronous machines to squirrel cage, exploited in the domain off the petrochemical industry, reveals that some failures are more frequent than others as exposed by diagram in (Figure1) presenting the percentage off defects susceptible to affect these high power machines. Figure 1: Percentage of defects Abdelkader Benbouaza et.al / International Journal on Computer Science and Engineering (IJCSE) ISSN : 0975-3397 Vol. 5 No. 04 Apr 2013 258