Rotor Failures Diagnosis of Squirrel Cage Induction Motors with Different Supplying Sources

Abstract

The growing application and the numerous qualities of induction motors (IM) in industrial processes that require high security and reliability levels has led to the development of multiple methods for early fault detection. However, various faults can occur, such as stator short-circuits and rotor failures. Traditionally the diagnosis machine is done through a sinusoidal power supply, in the present paper we study experimentally the effects of the rotor failures, such as broken rotor bars in function of the ac supplying, the load and show the impact of the converter from diagnosis of the machine. The technique diagnosis used is based on the spectral analysis of stator currents or stator voltages respectively according to the types of induction motor ac supplying. So, four different ac supplying are considered: ? the IM is directly by the balanced three-phase network voltage source, ? the IM is fed by a sinusoidal current source given the controlled by hysteresis, ? the IM is fed (in open loop) by a scalar control imposing through ratio V/f=constant, ? the IM is controlled through a vector control using space vector pulse width modulation (SVPWM) technique inverter with an outer speed loop.