The current installation rate of wind turbine generators is on track to meet DOE published goals of 20% wind source of electricity by 2030. As the most economical sites become populated, future installations will rely more heavily on low wind speed on-shore site locations and high wind speed off-shore or deep off-shore site locations. As higher power density evolves from 2.5 MW to 6-10 MW per turbine, 15 kV class distribution voltages become absolutely necessary for economical and efficient transfer of the electricity to the user base. A novel inverter system for direct wind power conversion will be developed with cost effective state- of-the-art high voltage wide bandgap (WBG) devices. The inverter system and circuits will be co- developed with the devices which are based on a novel electric field balanced power semiconductor design. The proposed field balanced device innovation significantly increases reverse blocking voltages from the ranges of 1200 V for typical WBG technology to medium kilovolt ranges necessary for the grid tie inverter design and prototyping. The high voltage direct inverter technology eliminates the step up transformer, inverter mass, copper wiring, tower mass, additional concrete, and other direct installation costs which increases the economic viability of low speed and off-shore installations. The proposed technology is applicable to gear driven Double Fed Induction Generators (DFIG), but it enables variable speed, gearless, direct drive Permanent Magnet Synchronous Motor (PMSG) wind systems to become more economically competitive.
