Thermal sensitivity analysis for TEFC induction motors

With the ever increasing pressures on electric motor manufactures to develop smaller and more efficient electric motors, there is a trend to carry out more thermal analysis in parallel with the traditional electromagnetic design. It has been found that attention to the thermal design can be rewarded by major improvements in the overall performance. Thus, accurate and reliable motor thermal models that can easily be incorporated into the motor designers software tools are required. In this paper one such thermal software package is described. Particular emphasis of the paper will be on using the software to fully analyse the thermal behavior of a range of total enclosed fan cooled (TEFC) induction motors. Concentration will be placed on sensitivity analysis, where the most important design parameters are varied and their effect on the temperature rise evaluated. This is useful to identify which parameters are important allowing robust designs to be developed which are insensitive to manufacturing tolerances.