Thermal management of compact SMT multilayer power converters

This paper presents thermal management considerations for a multilayer stacked converter construction technology Power Sandwich. The multilayer converters are built using novel x-dim components that have uniform height and double-sided SMT terminals. The SMT terminals of the components are soldered to two substrates and together with the substrate metallisation form copper-conductors reinforced multilayer assembly. Such structure has enhanced thermal performance as is shown in the paper. The concept enable more uniform distribution in the systems with non-uniform power loss distribution as proven by CFD simulations and experimental demonstrators, thus simplifying the design procedure of power sandwich converters. Analytical thermal models for forced and natural convection heat transfer from multilayer converters are developed and experimentally validated. The thermal design procedures and models are illustrated on constructed high power density sandwich demonstrators: 150W HID lamp electronic ballast and 2.2kW inverter for motor drive.