Compact, High-Power, High-Voltage, Bidirectional DC-DC Converter

The inherent limitations relating to power density, conversion efficiency, and thermal tolerance establish barriers to future development in key military, automotive, and aerospace applications. This research aims to overcome these limitations and develop an unprecedented compact, high power, high efficiency, high temperature, bidirectional dc-dc converter. The Phase I effort successfully demonstrated the feasibility of this converter through a unique marriage of state-of-the-art technologies in semiconductor packaging, power electronics system design, control design, and thermal management. The semiconductor packaging and thermal management innovations consist of developing a new IGBT/SiC diode package compatible with evaporative spray cooling (ESC) technology, with a substantial reduction in thermal resistance. The power stage is modular and consists of multiple, parallel connected, interleaved, and soft-switched units that have distributed heat load, lower losses, and smaller magnetics. Control of the system is performed through a mixed analog/digital hybrid scheme that combines speed and flexibility. The Phase II effort will consist of implementing, testing, and optimizing the techniques adopted in Phase I and will result in a prototype that meets the Army’s challenging requirements. In addition to military applications, the results of this research will also be valuable in commercial HEVs, renewable energy systems, and power electronic systems packaging.