Monitoring and diagnosis of failures in squirrel-cage induction motors due to cracked or broken bars

Rotor-Bar Breakage Mechanism and Prognosis in an Induction Motor

“… Applying for the first time crack propagation expressions in order to properly model that observed evolution, as opposed to the high cycle fatigue ones used in [17,18,19].  Confirming the effect of constructive rotor asymmetries in the incipient detection of this fault, not detected in previous partial breakage studies [12,13,14].  Yielding a complete CBM/PHM system able to monitor and predict the state of one rotor bar.…”

“…Recently, research has been focused on special aspects of rotor asymmetries, such as the load's influence in the traditional MCSA-based diagnosis [10], the effect of rotor ducts [11], partial breakage detection [12,13,14] and diagnosis in transient regime [15], under which the FFT analysis proves useless. In fact, one of the seminal works on transient current analysis, by Elder et Al., pointed out towards combining both of these approaches [16] in the study of direct startup transient since under such condition the machine is under severe electrical and mechanical stress, and thus faults as broken rotor bars could be detected at an earlier stage.…”

“…Previous studies have only been focused on diagnosing partial breakages [12,13,14].  Applying for the first time crack propagation expressions in order to properly model that observed evolution, as opposed to the high cycle fatigue ones used in [17,18,19].…”

Simplified hybrid PD model in voids: Pattern validation

“…Several diagnostic methods can be adopted to identify defects in insulation systems. This topic is of primary importance for renewable energy systems in which power electronics converters, generators and inverters are always included [1][2][3][4][5][6][7][8][9]. Electronics component are the core of Φ This publication was partially supported by PON PON01_00700-2010 "Ambition Power" Italian Research Programme.…”

Quantitative rotor broken bar evaluation in double squirrel cage induction machines under dynamic operating conditions

“…But inter bar currents produce core vibrations, which can be detected using vibration analysis techniques. The situation is more complicated when the frequency components characteristics of the rotor fault are very close to the fundamental one, and specifically under low load operating conditions [6][7]. In order to discern cases in which the presence of inter bars currents decrease the sensitivity of the MCSA, axial and radial vibrations analysis were investigated in [8], and more recently for double cage motor in [9].…”