Physical and electronic model of studying infrared radiator for drying wending insulation

Abstract

During a long shutdown of the motors, the insulation quality of the windings of asynchronous motors deteriorates due to moisture. This requires additional costs for drying the insulation of electrical machines. The signs and possible causes of malfunctions of electrical machines, as well as methods of drying insulation, are studied: Drying by external heating, Drying by heating from an external source, Convective drying, Drying by induction loss, drying using light emitters. Drying using infrared radiation is the mildest method and helps to maintain the quality of the insulation. The movement of moisture in the layers of insulating windings occurs according to the laws of heat-mass exchange, that is, heat and moisture are simultaneously transferred. In this case, heat is transferred from more heated layers to less heated layers and at the same time promotes moisture transfer. A physical and electronic model was developed to study the effect of infrared radiation on the drying process of insulation of electrical machines. The main factors influencing the process under consideration are the power of the radiation sources and the supply voltage, that is, the temperature changes in the layers of the insulated windings were studied depending on the change in the power of the emitters and the supply voltage. The created model was investigated according to the main features corresponding to the real process (even the geometrical dimensions coincide). An indispensable condition for physical modeling is the strict geometric similarity of the model and nature, as well as the equality of the corresponding similarity criteria in them.