Journal of Failure Analysis and Prevention

, Volume 14, Issue 2, pp 125–138 | Cite as

Experimental Investigation of Misalignment Effects on Rotor Shaft Vibration and on Stator Current Signature

  • Alok Kumar Verma
  • Somnath Sarangi
  • M. H. Kolekar


Misalignment is one of the most common faults in any rotating machine. It can cause decrease in efficiency and in the long run may cause failure of machine. Most of the researchers, consider only vibration information for the misalignment. However, this paper inspects the different types of misalignments by using diagnostic medium such as stator current signature as well as rotor vibration signal and it is being found that current signature alone can predict the misalignment effect without use of vibration signal. Diagnostic features obtained by FFT related to misalignments have been explained. Orbit plots are effectively used to explain the unique nature of misalignment fault. In this study, shaft displacement and stator current samples during machine run up under aligned as well as misaligned conditions are measured and analyzed. Result shows that misalignment is the parameter that is more responsible for the cause of instability.


Parallel misalignment Angular misalignment Fast Fourier transform Motor current signature analysis Fault diagnosis 



The authors would like to acknowledge the support provided by Indian Institute of Technology Patna for assistance with this work.


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Copyright information

© ASM International 2014

Authors and Affiliations

  • Alok Kumar Verma
    • 1
  • Somnath Sarangi
    • 2
  • M. H. Kolekar
    • 1
  1. 1.Department of Electrical EngineeringIndian Institute of TechnologyPatnaIndia
  2. 2.Department of Mechanical EngineeringIndian Institute of TechnologyPatnaIndia

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