Direct Drive AC Rim Motor for Responsive Energy Control of Alternative Electric Vehicle
Project Title
Direct Drive AC Rim Motor for Responsive Energy Control of Alternative Electric Vehicle
University
University of Idaho
Principal Investigator
Herbert Hess, Steve Beyerlein, Edwin Odom, Robert Fuhrmann, Russ Porter, Dan Cordon
U of I Electrical & Computer Engineering
PI Contact Information
U of I Electrical & Computer Engineering
Funding Sources and Amounts Provided
US Department of Transportation/TranLIVE — $50,000
University of Idaho — $50,000
Total Project Cost
$100,000
Agency ID or Contract Number
DTRT12GUTC17; KLK912
Start Date
8/25/13
End Date
1/31/16
Description of Research Project
This project will investigate environmentally sustainable and safe solutions for alternative vehicles by applying an innovative direct drive power train to a competition model SAE Formula Electric Vehicle. The project will increase the range and efficiency of an electric vehicle through improved regeneration capabilities and an innovative lightweight “rim motor” topology that converts energy closer to the point of use. Creating the improved regeneration algorithm, both hardware and software, and designing, building, and verifying the “rim motor” are the two major tasks of this project. This project advances electric vehicle safety by allowing for true four wheel direct drive. This improves vehicle turning radius, shortens braking time, prevents sliding due to loss of traction, and places both drive torque and regeneration directly at the wheels. Design, build, and verify advances in both regeneration and drive motors are of the essence of this project.
Implementation of Research Outcomes
The Formula Electric Vehicle’s mission is to create an all-electric vehicle capable of competing with comparable vehicles by May 2015. It will contain lithium polymer batteries with advanced battery management, a regenerative braking system based on a two-level ultracapacitor design, and a light weight smooth rotor induction motor with a torque controlled drive system.
- Senior design teams:
- Our first senior design team, composed of Electrical Engineering seniors, completed their work on battery design. They researched and chose Lithium Polymer cell modules by Haiyin for the battery that will eventually power the Electric Vehicle. They specified the battery’s performance, found cells to meet those specifications, and assembled a reduced-scale prototype. They specified and chose an EMUS Battery Management System, demonstrating its performance to be satisfactory for the eventual Electric Vehicle’s battery.
- Our second senior design team began designing the major subsystems of the Electric Vehicle. The design is challenging because the drive motors are wheel-mounted in an experimental motor topology. Mechanical Braking includes perimeter disc brakes with an inside caliper. Rapid Charging of a plug-in battery charger from three possible sources: 120VAC, 240VAC, and 480VAC. Regenerative Braking recovers energy from electromagnetic brakes, storing that energy in an experimental ultracapacitor configuration, and safely returning that energy to the batteries. Wheel Center, a design to mount the wheel and the experimental drive motor. Each of these projects has a design written and parts ordered for eventual completion in May 2014. Test stand and charging system were completed in May 2014.
- Graduate student:
- Supervised and mentored the senior design teams.
- Began the volunteer team that should complete and race the vehicle in mid-2015.
- As a result of an extensive literature search of motor designs, our graduate student proposed a continuum rotor design. Existing designs proved to be too weak on theory, so our student developed a solid theory based on the continuum electromechanics theory of James Melcher. Our new design uses a continuous metal (copper or aluminum) band as a rotor. It exhibits characteristics known of linear induction motors but now theoretically justified and in a rotor that can be easily mounted and has somewhat less mass than typical motors of similar ratings. Continuum mechanics was used to verify design methodology.
- Standard motor design methods were used to develop a working computer model of an inside out rim motor. This computer model enabled parts drawings to be created. Next would be to fabricate the motors and test them.
- Graduate thesis
- Veach, Giselle S., “Development, theory, and design of the image motor for automotive applications,” Master of Science thesis, University of Idaho, August 2014.
Impacts and Benefits of the Project
This is the second semester of this project. It has already had several benefits:
- Completion of a senior design project in which the batteries were specified, a reduced scale prototype assembled, and a battery management system selected and successfully proven with these batteries.
- Creation of a volunteer Formula Electric Vehicle team. Impact on education of more than 20 students as they design and build an electric vehicle.
- By determining that existing linear induction motor design equations are inadequate, new design equations advance the art significantly.
- Standard design equations were found to be relevant, thus these machines can be designed using standard techniques.
- Completion of a senior design project in which the goal was to develop a test stand enabled brakes and testing equipment to be built for testing inside out topologies.
- Completion of Masters thesis.
Web Links
http://www.mindworks.shoutwiki.com/wiki/Team_EV
http://www.mindworks.shoutwiki.com/wiki/Team-MESS
UI_TranLive_Direct-Drive-AC-Motor-KLK912
Keywords
- Electric vehicles