A new approach in insulation systems for rotating machines

Abstract

The possibility to increase operating performance and efficiency of an electric machine can be achieved through the improvement or modification of the components of the primary insulating material. Relevant variables in the construction of a machine can be found in the components of the insulating materials and their overall thickness. These components can influence the electric strength and overall service life. In addition, the electrical insulation system dictates the thermal classification and therefore the construction of a machine. It is understood that a thinner insulation exhibits a higher thermal conductivity than a comparable thicker one. By improving the thermal conductivity of the insulation through thickness reduction, it is possible to increase the current density in the conductors. However, with such a design change, the electrical strength and service life of the insulation remains an important consideration. An improvement in the thermal conductivity of a mica tape can be achieved through the addition of highly thermally conductive materials or by reducing the thickness of the carrier components. However, these alterations to a standard insulation often result in a decrease in the electrical and or the mechanical properties of the insulating material. In this paper, a new mica tape construction will be discussed. It will propose that it is possible to not only improve the mechanical and electrical properties of an insulating material, but to also reduce its overall thickness, while improving service life. The new development reduces the thickness of a standard insulating tape by 15%. With this achievement, both efficiency and power output of a machine design can be increased. Power calculations indicate that this increase is considered to be significant