The Problem:
Electric and hybrid electric vehicles use a permanent magnet structure to run their electric motors: permanent magnets are arranged so as to spin in reaction to changes in current and temporary magnetic fields. With current designs, there is a phenomenon caused torque ripple which causes unwanted noise, vibration, harshness, low fuel efficiency, and low durability of car components. Additionally, electric motors used in electric vehicles use expensive rare-earth metals in order to function as permanent magnets.
The Solution:
Researchers at the University of Alabama have developed a novel spoke construction of permanent magnets for electric motors. Through magnetic topographical analysis, an optimal arrangement of permanent magnets (that do not need to be rare-earth metals) and air gaps in the motor has been achieved. This rearrangement of components in the electric motor setup decreases torque ripple by 55% over current technology and increases total average torque by 7%. This technology provides cost benefits through use of less expensive magnets but it also creates an increase in overall motor efficiency.
3D View of Rotor Configuration
Rotor Configuration of Motor
Benefits:
• Decreases torque ripple by 55%.
• Increased total average torque by 7%.
• Reduced cost of electric motor without use of Rare-Earth metals (increasingly expensive).
• Technology used in the majority of electric motor vehicles.
• Less expensive, more efficient.
The University of Alabama Research Office of Innovation and Commercialization (OIC) is a non-profit corporation that is responsible for commercializing University of Alabama technologies and for supporting University research. At OIC, we seek parties that are interested in learning more about our technologies and commercialization opportunities, and we welcome any inquiries you may have.
