Application of Electric Vehicle System Design to Grand Prix EV Kart 2011-01-0353

The renewed interest in electric and hybrid-electric vehicles has been prompted by the drastic rise in oil prices in 2008 and launch of new initiatives by the Federal Government. One of the key issues is to promote the incorporation of electric drivetrain in vehicles at all levels and particularly with emphasis on educational activities to prepare the workforce needed for the near future.

Purdue University has been conducting a Grand Prix for over 50 years with Gas-powered Karts. In April 2010, an annual event was initiated to hold an EV Grand Prix where 17 EV Karts participated in the competition. Four of the participating teams comprised of Purdue students in a new graduate course for EV design and fabrication. Using the basic framework of the gas-powered Kart, an electric version was developed as a part of this course. Other participants were also provided with the guidelines and design parameters developed for the course and competition. Each EV Kart was powered by an electric motor rated at a nominal power of 11 kW (15 Hp) using Li-Fe batteries for energy storage. The vehicles are achieving racing speeds as high as 60 kph (37 mph) while being able to complete as many as 100 laps on the Purdue Grand Prix track in about 50 minutes.

The power management and control systems integrated with the inherent engineering of electrically powered vehicles are the focus of this paper. As a part of this effort, selected vehicles participating in the competition were evaluated in a dynamic fashion during and after the competition. Data was collected using onboard and wireless systems as well as static measurements for the evaluation purposes. Characterization of the battery charging and discharging was conducted to better understand the role of this critical component in the design. It became evident that driver experience and approach was one of the key factors in Kart performance and energy efficiency. To further examine that, data from novice drivers using the same karts and tracks were compared showing significant improvements in energy efficiency and performance with experienced drivers. The performance vs. design basis of the EV Karts used to recognize the value of various options will be discussed in the paper.