Germany awards G+L innotec funding for development of fuel cell technology using media gap motor: Project REZEBT
G+L innotec is an R&D service provider and concentrates on the development of the Media Gap Motor (MGM). The MGM is a permanent magnet synchronous motor (PMSM) with the special feature of a hermetically sealed system in which the stator inner diameter is oversized in relation to the rotor or the permanent magnet outer diameter.
This large air gap allows the transport of various media between rotor and stator in the axial direction. The rotor magnet can in this case be coupled directly to the conveyor or integrated into it.
Since 2009, the focus has been on the development of electrical assistance of turbochargers for combustion engines. G+L innotec is now expanding to include hydrogen applications, thus spanning the arc to electric mobility.
The joint project “Recirculation blower development for fuel cell technology” (REZEBT) together with The Institute of Turbomachinery and Fluid Dynamics (TFD) at the Leibniz University of Hannover (LUH), The hydrogen and fuel cell center ZBT GmbH, Duisburg, and G+L innotec, is to be completed by 2022.
The Federal Ministry of Economics and Energy (BMWi) has approved a grant for the project within the framework of the “Central Innovation Program for Medium-Sized Businesses (ZIM)”.
G+L innotec is in charge of the project management and is developing, designing, and implementing a cost-efficient and functionally reliable recirculation blower for Proton Exchange Membrane Fuel Cells (PEMFC) based on the MGM.
The design of the MGM developed by G+L innotec is characterized by a particularly large gap between magnet and coil.
In contrast to conventional electric motors, which try to realize the smallest possible gap, the MGM uses a large gap to transport the medium directly through the motor, thus cooling it at the same time. So what strictly speaking contradicts academic teaching, in fact gives the MGM an exceptionally high efficiency at high speeds. Both principle and function have been widely recognized and accepted.
What already enables a significant leap in the efficiency of combustion engines in the electrically assisted turbocharger today will optimize the efficiency of the fuel cell tomorrow and significantly extend its life-time.
On the one hand, the MGM will serve as drive for the axial, diagonal or radial recirculation blower—depending on the design—in which hydrogen is hermetically encapsulated and transported without dynamic seals. On the other hand, the MGM can also be used as a highly efficient electric compressor for the important air supply to transport oxygen into the fuel cell and water out of it.