High Damping Resin for Impregnation of Propulsion Scale Electric Machinery

In Phase I, Texas Research Institute Austin (TRI/Austin) developed a unique polymer system that exhibited excellent damping ability, with loss factors greater than 0.75 over much of the 80-120 degrees C temperature range at 120 Hz frequency. Stator modal analysis and finite element analysis verified the damping contribution of the resin. The resin also showed excellent dielectric strength and saltwater proofness under applied voltage. Based on these characterizations, it is feasible that this new epoxy-based material could be used as a VPI resin in propulsion motors to reduce the acoustic signature of the U.S. Navy’s electric drive system currently in development for the new DD(X) destroyer. During the Phase II, TRI/Austin will further improve the damping resin and perform additional screening tests and FEA. Structure-borne and airborne noise and vibration measurements will be determined for a 15-20 kW motor in which the stator has been impregnated with the TRI/Austin resin, with comparisons made to a motor impregnated with a Navy-approved resin. TRI/Austin is teaming with a designer and manufacturer of Naval electric propulsion motors for the DD(X) application, and with a VPI resin manufacturer that will provide critical testing and evaluation of the resin as an addition to their product line.