Developing Stator and Rotor Windings of Low-Voltage Alternators with Improved Lifetime Using Tailored Polyester Nanocomposites

The application of polymer nanocomposites is limited to the laboratory scale, and prototype development is yet to be reported in major applications. This study pursues a systematic approach of fabricating winding insulation of the low-voltage alternator using the novel polyester resin/hexagonal boron nitride (hBN) nanocomposite through standardized preparation and manufacturing processes. The optimal content of hBN nanofillers for fabricating of stator and rotor windings is determined through various preliminary tests. After that, a total of 24 prototypes of wound stators and rotors for low-voltage alternators (output voltage: 240 V) with different ratings (15 kVA and 30 kVA) are fabricated. These prototypes consist of polyester resin/hBN nanocomposite-based stator and rotor windings and special polyester insulating enamel gray coating mixed with optimal nanofiller content. The insulation resistance and polarization index measurements of fabricated prototypes are carried out. Furthermore, the thermal ageing of these prototypes is carried out at 160 °C and 180 °C to simulate the effect of higher operating temperatures. The results show that degradation-resistant and durable insulation systems with longer life can be developed using polyester resin/hBN nanocomposites for any ratings of low voltage rotating machine that uses polyester resin insulation.