Advanced Thermal Packaging for Power Converters

Technology Assessment & Transfer (TA&T) proposes to apply advanced cooling and packaging technology to substantially reduce thermal resistance between the heat producing components in aircraft power converter units and the polyalpha olefin (PAO) or fuel coolant. The proposal addresses the thermal packaging design of the primary heat sources in aircraft power converters: 1) power switching modules (i.e., IGBT and diode modules); 2) magnetic core inductors; 3) control electronics; and 4) capacitors. Reduced thermal resistance between these heat sources and the coolant will allow increased coolant inlet temperatures from nominally 35 °C to 65 °C and higher depending on the converter design. Higher coolant inlet temperature reduces the requirements of the aircrafts’ thermal management system, the design of which is driven by the lowest temperature power component in the system. This presents opportunity for size reduction of cooling system’s refrigeration components and heat exchangers. In order to fully realize the benefits of the proposed concepts, TA&T will collaborate with Honeywell Aerospace, a power and cooling system prime contractor for the F-35 Joint Strike Fighter. In Phase I a Honeywell power converter will be selected and proposed thermal packaging improvements will be analyzed to quantify thermal and weight reduction benefits. BENEFIT: As the DoD moves toward the More Electric Aircraft power converter units will increase in number. The packaging improvements developed here will provide significant weight savings for each converter unit and reduce the requirments of the aircraft thermal management systems.