This book covers the diagnosis and assessment of the various faults which can occur in a three
phase induction motor namely rotor broken-bar faults rotor-mass unbalance faults stator
winding faults single phasing faults and crawling. Following a brief introduction the second
chapter describes the construction and operation of an induction motor then reviews the range
of known motor faults some existing techniques for fault analysis and some useful signal
processing techniques. It includes an extensive literature survey to establish the research
trends in induction motor fault analysis. Chapters three to seven describe the assessment of
each of the five primary fault types. In the third chapter the rotor broken-bar fault is
discussed and then two methods of diagnosis are described (i) diagnosis of the fault through
Radar analysis of stator current Concordia and (ii) diagnosis through envelope analysis of
motor startup current using Hilbert and Wavelet Transforms. In chapter four rotor-mass
unbalance faults are assessed and diagnosis of both transient and steady state stator current
has been analyzed using different techniques. If both rotor broken-bar and rotor-mass unbalance
faults occur simultaneously then for identification an algorithm is provided in this chapter.
Chapter five considers stator winding faults and five different analysis techniques chapter
six covers diagnosis of single phasing faults and chapter seven describes crawling and its
diagnosis. Finally chapter eight focuses on fault assessment and presents a summary of the
book together with a discussion of prospects for future research on fault diagnosis.
