Drives and Controls Magazine

MoD contract could lead to efficient electric propulsion systems

26 August, 2009

Magnomatics, a Sheffield company which develops advanced magnetic transmission systems and high-torque electrical machines, has signed a six-figure contract with the British Ministry of Defence (MoD), under which it will conduct a detailed design study of a magnetically-geared propulsion motor, based on its patented “pseudo direct drive” (PDD).

Under the contract, the company will develop its technology to the megawatt scale, allowing the MoD to assess its potential for use in electric propulsion systems for future frigates and submarines. The project is due to be completed by April 2010, when the MoD will decide whether to devote more funds to taking the technology further.

The PDD system integrates magnetic gearing in a brushless permanent magnet machine to provide superior performance in low-speed, high-continuous-torque drive applications. It offers the potential for higher efficiencies in a much smaller package than other motor technologies

Magnomatics, which was formed in 2006 as a spin-off from the University of Sheffield’s machines and drives group, has also developed a range of gear technologies that use a high-torque magnetic gear invented by the company. The gears use permanent magnets to transmit torque between an input and output shaft without mechanical contact, thus reducing maintenance, improving reliability and raising efficiency compared to conventional gears.