Adamir Jahić, Željko Hederić, Mirza Atić

In recent years, problems of increasing energy efficiency and stability in the work of electric motor drives, are becoming more and more important. Reducing costs of production in many industries should necessarily modernize our technological processes, the introduction of modern electronic devices should raise the level of automation and modern methods of management and protection. Motor efficiency has been significantly increased per volume unit by improving the technology of motor production, which means that less volume per motor power decreases the thermal time constant; therefore, warming-up is faster under abnormal conditions. Advanced HV cage induction motors are constructed for high powers, dimensioned for precisely defined load, also with very low permissible overload. There are many different factors which influence operation of induction motors, and any deviation of some of those factors could cause damage to the motor. This paper will discuss the issues of failures on the high-voltage cage induction motor rotor, the causes of failures and their detection.
failures, high-voltage cage induction motor, rotor, thermal stress of electric motors.