Abstract
Motor current signature analysis (MCSA) based on the 50/60-Hz sidebands has become a common test in industry for monitoring the condition of the induction motor rotor cage. However, many cases of unnecessary motor inspection or outage due to false alarms produced by rotor axial duct interference have been reported. If the number of axial ducts and poles is identical, this can produce 50/60-Hz sideband frequency components in MCSA that overlap with that of rotor faults, resulting in false alarms. However, there currently is no practical test method available for distinguishing rotor faults and false indications other than testing the rotor offline or under the startup transient. In this paper, the feasibility of using the rotor fault frequency component produced by the space harmonic waves is evaluated as a solution for the first time. Since the fifth or seventh space harmonics have a spatial distribution of flux that does not penetrate in the rotor yoke to reach the axial ducts, they do not produce false alarms. The proposed method is verified on 6.6-kV motors misdiagnosed with broken bars via the 50/60-Hz sidebands of MCSA. It is shown that it provides reliable online indication of rotor faults independent of axial duct influence and can be used for screening out false alarms.
Original language | English |
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Article number | 6834794 |
Pages (from-to) | 1803-1813 |
Number of pages | 11 |
Journal | IEEE Transactions on Industrial Electronics |
Volume | 62 |
Issue number | 3 |
DOIs | |
Publication status | Published - 2015 Mar |
Bibliographical note
Publisher Copyright:© 1982-2012 IEEE.
Keywords
- Condition monitoring
- fault diagnosis
- frequency-domain analysis
- induction motor
- predictive maintenance
ASJC Scopus subject areas
- Control and Systems Engineering
- Electrical and Electronic Engineering