The Need

Magnetic gears offer compelling advantages over mechanical gearboxes (contactless torque transfer, reduced maintenance, and improved reliability) but widespread adoption has been limited by efficiency losses. A major contributor is “end-effect” loss, where magnetic flux leaks at the axial ends of the device and does not contribute to torque generation. These losses can account for a significant portion of total inefficiency, reducing torque density and system competitiveness relative to conventional gearing solutions.

The Technology

OSU engineers have developed a magnetic gear architecture incorporating Halbach array “cladding” magnets positioned at the axial ends of the machine. These engineered magnet arrays direct and concentrate magnetic flux toward the active regions of the gear, limiting flux leakage. By preserving usable magnetic flux within the system, the design improves torque transmission and overall magnetic efficiency without fundamentally altering the core gear topology.

Commercial Applications

• Wind turbine drivetrains and direct-drive generators
• Electrified transportation systems (EV powertrains, eVTOL propulsion)
• Industrial machinery in remote or low-maintenance environments
• Aerospace and offshore systems where lubrication-free operation is critical

Benefits/Advantages

• Reduced end-effect losses: Preserves magnetic flux that would otherwise be lost, improving efficiency
• Increased torque density: Demonstrated ~10% improvement in specific torque for comparable system size
• Enhanced system reliability: Maintains inherent benefits of magnetic gearing (contactless, low wear)
• Design compatibility: Can be integrated into existing magnetic gear architectures with minimal redesign