Highly Efficient, High Power Density GaN-based DC-DC Converters for Grid-Tied Energy Storage Applications

APEI, Inc. is proposing in this Phase I effort to design and build a scalable, high-efficiency, high-power density, gallium nitride (GaN)-based DC-DC converter for grid-tied energy storage applications. The project approach will utilize a soft switching dual active bridge DC-DC converter with state-of-the-art GaN power semiconductor switches and advanced power packaging techniques to efficiently transform energy from a battery energy storage system to a three-phase voltage-source inverter for subsequent insertion to the AC grid. This converter can work with any renewable or alternative energy source that produces an unregulated or uncontrolled DC voltage at its terminals. The goals of the Phase I project are to: i) compare several candidate DC-DC soft-switching converter topologies for high voltage, high power energy storage applications, ii) design a custom GaN-based power module demonstrating optimal thermal, electrical, and mechanical characteristics, iii) design and build a representative scalable prototype to demonstrate the efficacy of the selected GaN power module-based soft-switching converter topology, and iv) target the preliminary performance specifications provided in the solicitation in order to commercialize this technology for existing and emerging energy storage power conversion systems used for facility load peak shaving, energy arbitrage, renewable energy smoothing/buffering, and coincident peak reduction. APEI, Inc. will use its expertise in power electronics miniaturization and packaging to design and build a minimum volume and weight, high efficiency electronic converter that converts a DC voltage from a battery energy storage system at its input to a desired DC voltage at its output.