2011 R&D 100 Winner
Priceton Power DRIThe prospect of emissions-free energy and a reduced dependence on exhaustible fossil fuel resources are the well-known advantages of solar, wind, tidal, and geothermal renewable energy options. Less apparent is the vexing problem of reliability. The sun does not always shine, nor does the wind always blow.

In an effort to improve power intermittancy issues in the photovoltaic sector, Princeton Power Systems Inc., Princeton, N.J., and Sandia National Laboratories, Albuquerque, N.M., has developed the Demand Response Inverter (DRI) that is intended to improve throughput for solar-based renewable energy solutions. Compact and lightweight, with a power density of 100 kW/m3, DRI has a number of advantages over legacy power converters. It employs high-frequency central resonant link (CRL) power topology and associated algorithms to maximize the performance of each of the device‚Äôs four ports. Instead of standard pulse-width modulation inverters, which hurt semiconductor lifetimes and power efficiency by hard switching components, the DRI conducts soft switches that also lower electromagnetic interference and harmonics, reducing filtering requirements. In addition, a high-frequency isolation transformer eliminates redundant power-processing components. These and other innovations deliver a high-power tracking and conversion efficiency of 99% maximum point power tracking and more than 97.5% conversion efficiency.

Power inverter for photovoltaic systems

Princeton Power Systems Inc.
Sandia National Laboratories

Development Team

Princeton Power DRI Development Team
(l-r): Frank Hoffmann, Karl Mickelson, Paul Heavener, Richard Jaccard, Darren Hammell from Princeton Power Systems








Princeton Power DRI Development Team 2
(l-r): Abbas Akhil, Ward Bower, Sigifredo Gonzalez from Sandia National Laboratories



The Demand Response Inverter (DRI) Development Team
Mahesh Gandhi, Principal Developer, Princeton Power Systems
Abbas Akhil, Sandia National Laboratories
Richard Aspinall, Princeton Power Systems
Ward Bower, Sandia National Laboratories
Sigifredo Gonzalez, Sandia National Laboratories
Darren Hammell, Princeton Power Systems
Paul Heavener, Princeton Power Systems
Frank Hoffman, Princeton Power Systems
Richard Jaccard, Princeton Power Systems
Eugene Kocherov, Princeton Power Systems
Erik Limpaecher, Princeton Power Systems
Karl Mickelson, Princeton Power Systems