WARF TECHNOLOGIES

High torque density and high efficiency are two of the most desirable features of electrical machines. A significant amount of research over the past two decades has focused on improving these parameters. Several new motor topologies have been proposed to increase efficiency and torque density; however, these designs use rare earth magnets (i.e., neodymium-iron-boron magnets), which drive up the materials cost of these machines. In addition, some of these topologies are restricted to low speed applications.

UW-Madison researchers have developed a machine topology suitable for high speed applications that simultaneously exhibits high efficiency and high torque density. Their dual-rotor, radial-flux, toroidally-wound, permanent magnet machine also employs inexpensive ferrite magnets, making these machines inexpensive to produce.

• Aeronautics
• Wheel motors for hybrid vehicles
• Generators

• Provides both high torque density and high efficiency
• Possesses high overload capacity
• Low-cost
• Suitable for moderate speed and high speed applications

Publications

• Ronghai Qu R. and Lipo T.A. 2004. Design and Parameter Effect Analysis of Dual-Rotor, Radial-Flux, Toroidally Wound, Permanent-Magnet Machines. IEEE Trans. Ind. Appl. 40, 771-779.
• Ronghai Qu R. and Lipo T.A. 2003. Dual-Rotor, Radial-Flux, Toroidally Wound,Permanent-Magnet Machines. IEEE Trans. Ind. Appl. 39, 1665-1673.

Tech Fields

• Engineering : Electric machines