Recent Developments of Electrical Drives - Part 43. The book stating the recent developments of electrical drives, can be useful for engineers and researchers investigating and designing electrical and electronic devices as well as for students and young researchers dealing with electrical and electronic engineering, computer sciences (advanced computer modelling, sophisticated control systems with artificial intelligence tools applied, optimal design bye use of classical and genetic algorithms employed), applied mathematics and all the topics where electromagnetic, thermal, mechanical phenomena occur | 422 Pereirinha and Antunes It was also numerically verified that as expected the thermal equivalent conductivity ke for each mesh is independent of the thermal source densities and boundary temperature. Indeed the problem was solved for two other different values of current densities two and four times more and two different values of boundary temperatures which lead to the same results as those obtained by the original bar with the same conditions. Conclusions The presented method seems to be able to calculate very accurately the global equivalent thermal conductivity of any bar with several thin insulation materials and not trivial geometries with only conduction heat transfer. It has been shown that the equivalent thermal conductivity depends on the mesh used. The method performs a very good fitting of the hot spot temperature in the considered multilayer insulated bar in electrical machine slot with much less computational costs than modeling all the insulation materials. The numerical thermal solution was checked by verifying that the total heat flux through the bar boundary was equal to the thermal sources applied. References 1 E. Matagne Macroscopic Thermal Conductivity of a Bundle of Conductors Conference on Modelling and Simulation of Electrical Machine and Static Converters IMACS TC1 90 Nancy France September 1990 pp. 189-193. 2 E. Chauveau E. Zaim D. Trichet J. Fouladgar A statistical approach of temperature calculation in electrical machines IEEE Trans. Magn. Vol. 36 pp. 1826-1829 2000. 3 M. Dodd The Application of FEM to the Analysis of Loudspeaker Motor Thermal Behavior 112th Audio Engineering Society Convention AES 112th Convention München Germany May 2002. 4 J. Holman Heat Transfer 6th edition New York McGraw-Hill Book Company 1986. 5 . Coulomb . Sabonnadiere CAO en Electrotechnique Paris France Hermes Publishing 1985 pp. 41-43. 6 J. Pinto . Antunes Coimbra Influence of the Thermal Dependency of the Windings Resistivity in the Solution
