Experimental investigation of the thermal parameters for modelling non-infiltrated concentrated windings

Abstract

Thermal analysis is an important aspect of electrical machine design. Thermal modelling of the windings is challenging, as a number of physical and manufacturing parameters need to be accurately reflected in the thermal model. Lumped parameter thermal models have been applied to machine windings for some time. These require a calibration of the thermal parameters. The thermal parameters are often assumed to be constant, and a function of the windings' construction process. While this may be true for epoxy infiltrated windings, this paper experimentally demonstrates that that the thermal parameters of non-infiltrated windings vary with heat flux. This finding challenges the notion that thermal resistances are only dependent on the manufacturing process, and thus with the operating point of the machine and its cooling mechanism.