Air Cooling of Power Electronics Through Vertically Enhanced Manifold Microchannel Systems (VEMMS)

Optimum thermal management of power electronics is necessary for their improved reliability and efficiency. Next generation electronics systems are predicted to dissipate more heat as die size shrinks and power levels increase. Traditional air-cooling approaches usually provide insufficient performance or require heavy and bulky heatsinks to achieve adequate thermal management. To tackle this, a novel air-cooled vertically enhanced manifold microchannel system (VEMMS) was developed. While minimizing the footprint requirement on the printed circuit board, it offers an efficient thermal management in a conformal scheme that accommodates the associated power electronics and their electrical connections. The present work describes manufacturing of the air-cooled VEMMS heatsink, and its experimental characterization and thermo-fluidic performance. Good agreement was obtained between the test results and numerical predictions. Using air at ambient conditions, a thermal resistance of 2.6 K/W was achieved, at 1.5cm2 footprint and 2cm3 total heatsink volume in a single-sided cooling architecture, enabling a full-bridge electrical power density of ~84 kWe/L and overall DC-DC converter's power density of ~20kWe/L, at reasonable flow rates and pressure drops using commercially available miniature electric fans. Index Terms-Air cooling, heatsink, manifold microchannel cooling, power electronics, power density, thermal management