Design of high thermal conductivity insulation adhesive (H-class) for low voltage motor

Abstract

In order to reduce the winding temperature furthest, we adopted the method of adding micron-grade filler to ET-90 base resin, and prepared three kinds of modified highthermal conductivity adhesive specimens (H-Class). At the same time, four kinds of performance tests (water-absorption, adhesive-strength, breakdown-strength, thermalconductivity) had been done for them, the test results showed specimen III adhesive had a highest thermal-conductivity (0.31 W/m.K), and finally specimen III adhesive was selected for testing. A new insulating system was developed, it consists of specimen III adhesive, self-made slot wedges and insulating paper. We applied the new insulating system to motors, and observed the changing results of winding temperature and noload loss. The results showed that the winding temperature could decrease by about 7 K from before, the no-load loss also has a decrease correspondingly. In the meantime, the motor efficiency increases by 0.7% compared to the original state and improves to nearly 86.6%. Thus, this research indicates that this new high thermal-conductivity adhesive (H-Class) could lower temperature in the windings and improve the motor efficiency simultaneously, it is of great significance in practical application.