Mechanical Characteristics Investigation of Mica-Containing Insulation of High Voltage Rotating Machines

There are few literature data about mechanical characteristics for stator bars insulation of high voltage rotating machines. In the present paper mechanical characteristics under static bending of mica-containing insulation are presented. Experimental samples were prepared using industrial equipment with two technologies - Resin Rich and Vacuum Pressure Impregnation. Determination of mechanical characteristics was conducted with three-point loading system. The results showed that at a temperature of 20 °С insulation system created by Vacuum Pressure Impregnation technology has advantages against Resin Rich technology. However, the first one has a significant decrease in mechanical characteristics when the temperature value rises up to 155 °С. According to thermal gravimetric analysis, this fact is caused by the chemical structure of the binder. The results can be useful in the design of rotating machines operating at high temperatures.