Design Considerations for High Power Inductors in DC-DC Converters

The demand for high density power conversion systems has led to numerous material developments for passive circuit components. Typically, these innovations improve thermal capabilities, enable higher switching frequencies, and increase component efficiency. For inductors, research has focused on formulating low-loss core materials such as distributed gap and nanocrystalline alloy materials that can be manufactured in appropriate core geometries. This paper presents a discussion of design trade-offs for core and winding implementations using these materials. Empirical results for power loss as well as temperature rise based on thermal management are presented for both distributed gap and nanocyrstalline alloy cores used in a high power DC-DC converter.