UQM hybrid vehicle combines 10-to-1 constant power speed ratio, full wave commutation

UQM Technologies has delivered a John Deere hybrid electric concept vehicle incorporating 10-to-1 constant power speed ratio (CPSR--the ratio between the top speed of a motor and its base speed) and full wave commutation technology.

UQM said its permanent magnet electric propulsion systems achieve a 10-to-1 CPSR and offer high torque and high-speed capabilities beyond those of other hybrid motor technologies.

Full wave commutation is a proprietary method of electronically controlling a permanent magnet propulsion system. UQM said the technology increases the peak power output of UQM motors by 33%, and continuous power output by 10%. It improves system efficiency from 2% to 8% depending on the operating point.

"By incorporating these proprietary technologies, we are able to achieve unparalleled acceleration, top speed and efficiency, while eliminating the conventional transmission," said UQM president and chief executive officer William G. Rankin. “We are excited about the potential for these technologies in the emerging market for hybrid electric vehicles, particularly for large vehicles in the over-the-road truck, agricultural, construction, mining and military market segments.”