Detection and analysis of eccentric failure in medium power threephase squirrel cage asynchronous motors using finite elementmethod

Squirrel cage induction motors are highly preferred in the industry due to their simple structures, low costs, high efficiency, and energy-saving capabilities, as well as their minimal maintenance requirements. Therefore, faulty conditions of squirrel cage induction motors have been the subject of many studies. In this study, a comprehensive examination is conducted, covering the formation of eccentric faults to faulty conditions. Eccentric fault refers to the disruption of the homogeneously distributed air between the stator and rotor. This fault is divided into three categories: static, dynamic, and mixed eccentric faults. The occurrence of the fault depends on various factors from the motor's design to its operating conditions. With the emergence of the eccentric fault, the motor experiences imbalances in air gap, magnetic flux density, noise, heating, changes in torque waveform, and instability in the load.In the study, an 11 kW, 4-pole squirrel cage induction motor belonging to the premium high-efficiency class is examined. Different types of faults and their intensities are investigated using the finite element method for the purpose of comparing a healthy motor with a motor experiencing eccentric faults. Healthy and faulty motors are compared using the finite element method, and the simulation results support the analysis. The Ansys Maxwell program, utilizing the finite element method, is a software package that facilitates the evaluation of behaviors and faulty conditions before the design phase. By comparing modeling and simulation results, the interpretation of parameters such as magnetic flux density, torque, vibration, and noise within the scope of eccentric faults is examined. The detailed impact of various fault intensities on the motor is thoroughly investigated. Thus, all the results regarding the parameters to be monitored in detecting eccentric faults are presented in this thesis