The following aspects will be comprehensively discussed in present chapter: to introduce the eccentricity-related indices in time, frequency and time-frequency domains commonly used in condition monitoring of induction motors; to investigate the effect of motor loading; to investigate the effect of various supply modes; to investigate various fault severities and types; to characterize faulty motor losses; and to provide more technical aspects of the diagnosis process of eccentricity fault which might affect the diagnosis process.

Chapter Contents:

• 9.1 Introduction
• 9.2 Effect of mixed eccentricity fault on time-domain variation of speed and torque signals
• 9.3 Normalized splitting severity factor
• 9.4 Ratio of area enclosed by stator current in two consecutive cycles to average area of two stator current cycles
• 9.5 High-frequency components of stator current
• 9.6 Low-frequency components of stator current
• 9.7 Joint analysis of low- and high-frequency patterns of stator current
• 9.8 Low-frequency components of voltage space vector and high-frequency components of current space vector
• 9.9 The ratio of sum of right (high) and left (low) sideband components to no-load current
• 9.10 Negative sequence current
• 9.11 Harmonic components of instantaneous power
• 9.12 Loss characterization of induction motors with eccentricity fault
• References

Inspec keywords: fault diagnosis; induction motors; condition monitoring; time-frequency analysis

Other keywords: faulty motor losses; condition monitoring; eccentricity-related indices; time-frequency domains; induction motors; motor loading; eccentricity fault; fault severities

Subjects: Asynchronous machines; Mathematical analysis