The high voltage electrical insulation systems with higher thermal conductivity

The electrical-insulation systems (EIS) of the electrical rotating machines have excellent electrical insulating and mechanical properties, but have a relatively low value of thermal conductivity. This work describes how micro fillers of aluminum oxide (Al₂O₃) can affect the thermal properties. Thermal conditions in the electrical rotating machine were modeled by finite element method 2D SW FEMM. The samples were measured for tan δ depending on the frequency and on temperature. Furthermore, the samples were measured for absorption and resorption currents, volume resistivity and dielectric strength. The sample was made with the use of an epoxy resin with the addition of micro fillers of Al₂O₃ (2%, 4%, 6%, 8% and 10%).