THERMAL MODELLING OF INDUCTION MACHINE USING THE LUMPED PARAMETER MODEL

Thesis Overview

<p> </p><div>This thesis is concerned with the thermal modelling of the induction machine. With the increasing quest for miniaturization, energy conservation and efficiency, cost reduction, as well as the imperative to exploit easier and available topologies and materials, it becomes necessary to analyze the induction machine thermal circuit to the same tone as its electromagnetic design. This would help in achieving an early diagnosis of thermo-electrical faults in induction machines, leading to an extensively investigated task which pays back in cost and maintenance savings. Since failures in induction machines occur as a result of aging of the machine itself or from severe operating conditions then, monitoring the machine’s thermal condition becomes crucial so as to detect any fault at an early stage thereby eliminating catastrophic machine faults and avoidance of expensive maintenance costs. Faults in induction machines can be broadly classified into thermal faults, electrical faults and mechanical faults. Currently, stator electrical faults are mitigated by recent improvements in the design and manufacture of stator windings. However, in case of machine driven by switching power converters the machine is stressed by voltages including high harmonic contents. The latter option is becoming the standard for electric drives. A solution is the development of vastly improved thermal system cum insulation material. On the other side, cage rotor design is receiving slight modifications, apart from that, rotor bars breakage can be caused by thermal stress, electromagnetic forces, electromagnetic noise and vibration, centrifugal forces, environmental stress.</div><div><br> </div><br><p></p>