WARF: P150249US01

Axial Flux-Switching Permanent Magnet Machine for High Speed Operation


Bulent Sarlioglu, Ju Hyung Kim, Yingjie Li

The Wisconsin Alumni Research Foundation (WARF) is seeking commercial partners interested in developing a redesigned axial FSPM machine that boosts efficiency and is ideal for high speed applications.
OVERVIEWHigh speed electric machines are needed in many applications including HVAC, industry, flywheels, fans, fuel-efficient vehicles, aircraft and much more.

Flux-switching permanent magnet (FSPM) machines are a promising option because they offer better cooling, simpler rotor construction and reduced reliance on rare earth materials. However, they have difficulty reaching high speeds. This is because current designs require high fundamental frequency to turn the rotor and allow the motor to operate. Such high fundamental frequency may not be attainable with today’s power electronic converters.

There are two FSPM topologies: radial and axial. In general, axial topologies have a more compact footprint and are ideal where space is at a premium, such as in-wheel vehicle drives.
THE INVENTIONUW–Madison researchers have developed a new axial FSPM machine that can be run at high speed with less fundamental frequency required, therefore overcoming one of the largest barriers to adoption. The new design features innovative axial flux topologies with offset rotor and/or stator structures.
  • Compressors, fans, pump motors, traction motors in hybrid and electric vehicles, aerospace motors and generators, and more
  • Ideal for high speed applications (also for medium and low speeds)
  • Achieves up to 60 percent reduction in fundamental frequency
  • Reduces core losses, copper losses and inverter switching losses
  • Increases efficiency and power density
STAGE OF DEVELOPMENTThe researchers have performed simulations and plan further prototyping.
Contact Information
For current licensing status, please contact Michael Carey at or 608-960-9867.
The WARF Advantage

Since its founding in 1925 as the patenting and licensing organization for the University of Wisconsin-Madison, WARF has been working with business and industry to transform university research into products that benefit society. WARF intellectual property managers and licensing staff members are leaders in the field of university-based technology transfer. They are familiar with the intricacies of patenting, have worked with researchers in relevant disciplines, understand industries and markets, and have negotiated innovative licensing strategies to meet the individual needs of business clients.