By Dr. Patrick McCluskey
There are strong incentives to reduce the size of advanced power electronics. Reduced system size often lowers parasitic losses, system weight, and system cost. Two items significantly limiting such reductions in size, however, are the following: 1) the dimension of magnetic devices such as transformers; and 2) the size of the cooling system, including heat sinks, required to dissipate the heat generated in the transformer windings. This webinar will discuss an advanced transformer configurations that allows for significant volume reduction by using additive manufacturing (AM) to deposit planar transformer windings on a thermally conductive combined-core-and-coil (C3) cooler substrate. The candidate material of the C3 cooler is ceramic, as it needs to be electrically insulating but thermally conductive. Windings are deposited on this cooler substrate by syringe printing and sintering of nano-silver (nano-Ag) and other conductive pastes, making the design flexible and sustainable. This paper will also detail the effect of the sintering process times and temperatures on electrical resistivity and adhesive bonding strength. Microstructural evolution in the sintered paste will also be addressed.