DC-DC Converter

Contact EMPS for commercial sample availability!

EMPS initial product is a high efficiency DC to DC converter product ideal for photovoltaic systems and wide variety of hybrid renewable energy systems including fuel cells, battery, micro-wind, tidal, geothermal and biomass.

The EMPS converter accepts a wide input voltage range (17 to 70 volts) and provides 400V DC output. This is the ideal DC bus voltage for 240V AC inverters used in North America. A different version supporting 600V DC is offered for European markets using 400 AC systems.

The DC-DC converter can be used with the EMPS inverter (in development) for the North American market grid-tied systems, or third party inverters, or by itself for a standalone DC power systems.

The EMPS DC-DC converter uses a proprietary converter topology called V6. It enables the most efficient, high power DC-DC converter system. The graph below shows the efficiency of the current 5KW system with different output fall times (or gate resistance). The V6 converter delivers peak efficiency of up to 97%. It also can deliver-and with 95% over the range of 20% to 120% of rated power.

In comparison other high power converters systems can only deliver efficiencies in the range of 85%. The improved efficiency of the EMPS converter enables new many new markets for this technology with EMPS owning exclusive worldwide rights and patents to renewable energy applications.

The V6 DC-DC converter was developed by Dr. Jason Lai, Director of the Virginia Tech Future Energy Electronics Center. It has been licensed exclusively to Emps for worldwide renewable energy applications (except Solid Oxide Fuel Cells). Dr Jason Lai is also the Chief Technical Officer of Emps. The V6 DC-DC converter was development began under a United States Department of Energy grant for Solid Oxide Fuel Cell research. The U.S. Department of Energy announced, on February 9, 2005, a significant advancement in fuel cell technology, stating, "Researchers at Virginia Polytechnic Institute and State University, working under a research grant managed by the National Energy Technology Laboratory, developed a highly efficient converter that can boost low DC (direct current) voltage produced by solid oxide fuel cell stacks to the higher voltage required (DC) for conversion to AC (alternating current) for household and commercial applications. The boost is significant because it provides another technological step in increasing the efficiency, and reducing the size and cost of fuel cells.

The release further noted, "The significance of Virginia Tech's work is that it facilitates the downsizing of the fuel cell stack and boosts net power output, while at the same time reducing the size and cost of the electronic systems behind it-key technical objectives for maturing solid oxide fuel cell technology to commercial-market self-sustainable status - Virginia Tech's device, the V6, when combined with highly efficient switching and digital control techniques, converts 22 volts to 400 volts at 97 percent energy efficiency. The device is able to boost voltage and reduce 120-hertz ripple current to 2 percent without the costly, bulky capacitors or additional converters that are customarily used. The net effect is that fuel consumption, the size of fuel cell systems, and costs are reduced, thereby taking a significant step toward the Solid State Energy Conversion Alliance Program's (SECA) goal of 40-60 percent overall fuel cell efficiency at a capital cost of $400 per kilowatt by 2010."

See and hear Dr Jason Lai discuss the technical advances of the 6phase DC-DC converter for fuel cell and PV applications