Rotor failures diagnosis of Induction Machines by current or voltage spectrum analysis in function of the type of feeding and the load

The numerous qualities of squirrel cage Induction Machines (IM) enchance their use in industry. HOwever, various faults can occur, such as stator short-circuits and rotor failures. In the present paper, the effects of the rotor failures, such as broken rotor bars, are studied experimentally in function of the type of induction mtoor feeding and the load. The diagnosis technique, which is used, is based on the spectral analysis of stator currents or stator voltages respectively according to the type sof induction motor feeding. So four different feedings are considered: - the IM is directly connected to the balanced three-phase network; - the IM is fed in by a sinusoidal current coverter controlled by hysteresis, - the IM is fed (in open loop) by a scalar control imposing the ratio V/f=constant, - the IM is controlled through a vector cotnrol with an outer speed loop.