Today's technologies slipped into vehicles starting on tracks of all sorts.
Whether it is endurance racing, top-speed competition or drag racing, technology transfer from the track has a major influence on what shows up in dealership showrooms and subsequently our bays. Without a doubt, this relationship is symbiotic in nature, as racing relies heavily on sponsorship from the major manufacturers. NASCAR pioneer Junior Johnson summed it up well when he said, "The best way to make a small fortune in racing is to start with a big one." The highly competitive teams in any form of racing would not exist without the monetary resources of their sponsors, which represent a broad spectrum of industry and organizations. This mutual dependence goes far beyond finances, however, as racing also is influenced by major societal trends. As the world changes, racing is being forced to change with it.
In recent years, we have witnessed a shift in attitudes regarding energy and environmental issues. This has led to a renaissance in automotive design, with a major push being made to reduce the environmental impact associated with personal transportation. Cars are being made lighter, with more exotic materials being used to replace conventional cast iron and steel. Alternative fuels also are being promoted in an effort to reduce dependence on foreign oil. More significantly, the very nature of the automotive power train is changing, with a gradual shift from mechanical and hydraulic systems to electric drives. These trends are having an impact on the world of racing.
Of course, racing always has been about building cars lighter, but alternative fuels and electric drives are relative newcomers and only now are being acknowledged as important considerations in the rulemaking process. Motorsports sanctioning bodies are working to incorporate these themes into their rulebooks, with the prize of increased audiences and a broader sponsorship base in the wings.
Excellent progress has been made on some fronts, with rule changes that nurture participation from progressive race teams. Here are a few examples of how electric vehicle (EV) and hybrid-electric vehicle (HEV) technology is making inroads into the world of racing.
Formula 1
The Kinetic Energy Recovery System (KERS) was introduced in Formula 1 (F1) for the 2009 race season. KERS is a form of regenerative braking: recover energy that ordinarily would have been lost as heat during the braking process, store it and then use it again later to help accelerate the car. Regenerative braking is used extensively in production HEVs and represents the lion's share of a hybrid vehicle's efficiency gains.
The motivation for allowing KERS in Formula 1 included development and promotion of environmentally-friendly technologies for use in production vehicles. From a race fan's perspective, KERS also would help with overtaking other cars and decreasing lap times, potentially increasing race excitement.In the case of F1, three possible types of KERS are allowed: electrical, mechanical and hydraulic. Hydraulic KERS stores braking energy as hydraulic pressure, which is then used to drive the rear wheels when acceleration is desired. Very few, if any, F1 teams have opted to use the hydraulic system. Another KERS version that has seen limited use is the mechanical system utilizing a flywheel that is housed in a vacuum and spins up to 80,000 rpm. When more power is needed, the flywheel is connected to the car's rear wheels. Despite the higher efficiency of the mechanical system, most F1 teams have opted for the electric version, which is similar to HEV technology.
Electric KERS uses a motor-generator unit attached to the car's transmission, which generates electricity during deceleration and uses it to charge a high-voltage battery pack. When the driver pushes the boost button on the steering wheel, the motor-generator switches to its motor function and uses electricity from the battery pack to provide up to 80 bhp to the car's power train. The driver is limited to a total of 6.67 seconds of boost time per lap to encourage strategic use of the stored energy.While KERS was first used in F1 during the 2009 race season, its use was suspended in 2010 by a gentlemen's agreement that appears to have been driven mostly by economic concerns. KERS has been reestablished for the 2011 race season, and while its use has always been optional, race teams recognize the serious handicap they will suffer if they opt out.
Le Mans Racing
One of the grandest traditions in motorsports is the 24 hours of Le Mans, an endurance race that takes place annually in Le Mans, France. With its inaugural race taking place in 1923, the 24 hours is among the toughest races in the world, and has spawned race series in Europe and in North America.
Le Mans racing is sanctioned by the Automobile Club de l'Ouest (ACO), which is tasked with crafting race regulations that encourage competition and address current trends in automotive technology. The ACO has demonstrated progressive thinking in the past, one example being the inclusion of diesel-powered sports cars in the Prototype class. This led to a revolution of sorts as diesel entries now dominate the LMP1 class and have been overall winners at Le Mans every year since 2006.Le Mans racing is conducted in North America under the auspices of the International Motor Sports Association (IMSA). While ACO regulations are used as primary guidelines, IMSA plays a role as the secondary sanctioning body for American Le Mans Series (ALMS) racing. In the recent past, the ACO has included language in Le Mans regulations that allows for hybrid car competition in the LMP1 (Prototype 1) class. While the ACO hybrid rules apply only to the LMP1 class, hybrid GT sports cars already are competing in Le Mans races as unclassified entries. One example is the Porsche 911 GT3R, which debuted in the 2010 ALMS race season at Road Atlanta.
The Porsche hybrid uses a unique electromechanical system for storing energy on the car. Where most regenerative braking systems would use either a flywheel or a battery pack, the Porsche hybrid utilizes a flywheel-based motor-generator as the energy storage medium. Porsche refers to this unit as the electrical flywheel battery. When the vehicle is braking, two motor-generators attached to the front wheels switch to generator mode and produce electric current. This current is then sent through the power electronics that control the three-phase energy-storage motor.The energy-storage motor's rotor is constructed using a heavy flywheel with permanent magnets on its inner circumference. The idea is to spin the flywheel-based rotor up to speed when the car is braking, then use the rotor's kinetic energy to produce electric current when the car is accelerating. When the boost paddle on the steering wheel is pressed, the energy-storage motor becomes a generator and the flywheel's kinetic energy is converted into electricity used to power the electric motors at the front of the car. A fully-charged energy storage motor will spin at 36,000 rpm and can provide additional power for up to eight seconds.
Another unique aspect of the Porsche 911 hybrid's design is that it is four-wheel drive. With the conventional internal combustion engine power train in the rear of the car, the hybrid system drives the front wheels and gives the car an advantage in wet conditions. With two ALMS races under its belt, look for Porsche hybrid technology to be prominent at future Le Mans race events.
Electric Drag Racing
While hybrid and EV racing has been championed by corporate sponsors in many race series, EV drag racing is moving forward mostly due to efforts on the part of grassroots pioneers. The National Electric Drag Racing Association (NEDRA) was formed in 1997 by a group of EV racing enthusiasts, many of whom still are active in the organization and on the track. NEDRA organizes electric cars and motorcycles into various classes, and writes rules to ensure safety and nurture competition. NEDRA race events are conducted around the country, with new records being set regularly as the EV race teams get more finely tuned.Internal combustion engine (ICE) vehicles traditionally have dominated drag racing culture. The National Hot Rod Association (NHRA), for example, was formed in 1953 and wrote its original rules so only internal combustion engines were allowed in its race events. After persistent lobbying by NEDRA members, the NHRA adopted EV rules in 1999 so electrics could run in sanctioned events as well. While the "EV paradigm shift" has been slow in coming, most race fans are astounded when they witness the speed EV dragsters demonstrate on the track.
Sponsorships are few and far between in EV drag racing, but this has not dampened the enthusiasm of its diehard proponents. One example is that of Mike Willmon, current NEDRA president and owner of the Crazy Horse Pinto EV drag car. Based in Palmer, Alaska, Willmon is an electrical engineer by trade and has been running his self-financed EV drag car at his local track as well as in the Pacific Northwest.
The 1978 Ford Pinto conversion involved removing the engine, transmission, exhaust system, fuel tank and radiator, and replacing those items with an electric power train. Two 9-inch diameter electric forklift motors are connected end-to-end and occupy the engine compartment and transmission tunnel. These are series-wound brush-type DC motors that are capable of producing 1,500 pound-feet of torque. Because electric motors generate three to five times as much torque as a comparable ICE, no transmission is necessary. The immense torque is sent to a Ford 9-inch rear axle with 4.11 gears, which replaces the original 8-inch unit.The rear of the car houses 850 pounds of lead-acid batteries, which represents about a quarter of the car's total weight. A total of 60 absorbed glass mat (AGM) batteries are connected in two strings of 30, making two 360-volt battery arrays in parallel. While the motors are rated at 36 to 48 volts in their normal industrial application, feeding 180 volts to them (they are connected in series at the beginning of the race) produces around 180 horsepower each. Battery power is metered using a specially-built controller which utilizes insulated gate bipolar transistors (IGBTs) to send up to 2,000 amperes of current to the motors.
In its current configuration, the Crazy Horse Pinto is capable of 12-second quarter miles. The one change that would go the furthest towards improving performance would be a switch to lithium-ion batteries. This would increase the battery pack's specific energy and shave almost 600 pounds off the car's weight.Willmon estimates that these batteries would last two to three times longer and would lower quarter-mile times by 1.5 seconds. In the absence of sponsorship, the full weight of these improvements falls on the car owner. This is not an unusual story in EV drag racing, but could become less common as the automobile makes the transition from mechanical to electric drive. Can the future come too soon? Not in the minds of the pioneers in the ranks of NEDRA.
Final Thoughts
The world of racing is changing in step with changes in our personal mobility. Some race series' are more progressive than others, but we are witnessing a silent revolution as electric technologies are developed to address energy and environmental issues. One thing is certain: The ride isn't going to be boring, it might even be electrifying!
Tony Martin is an associate professor of automotive technology at the University of Alaska Southeast in Juneau, Alaska. He holds Canadian Interprovincial status as a Journeyman Heavy Duty Equipment Mechanic. He also has 19 ASE certifications, including CMAT, CMTT, L1 and L2.
For the full story, visit MotorAge.com/ ElectricalMS To see more articles on this subject, visit MotorAge.com/ Electrical
