Using kinetic energy recovery systems (KERS) in Formula One racers remains a controversial issue, but teams are moving forward with systems that store energy created during braking. Magneti Marelli and McLaren Electronic Systems are advancing their designs, working closely with partners from the electronics industry.
The Fédération Internationale de l'Automobile is promoting KERS as green technology. It uses hybrid regenerative braking that recovers kinetic energy during braking, storing that energy so it’s available to give the racer a boost. Regulations limit to 0.4 MJ (0.11 kW·h) the amount of energy stored during each lap and to 60 kW maximum power to the wheels at any given time. Normally, that energy is lost as heat.
Most F1 teams are striving to get efficient systems in place, but some have criticized the technology. Ferrari believes the technology is too expensive, with little benefit. That’s partially because some developers contend that the power-to-weight ratio of KERS components needs to be a factor of three or four above that seen in on-highway hybrid vehicles. Adding a new system with batteries can also alter the balance of the vehicle. Nonetheless, all F1 teams are moving forward with designs.
Many of these systems are being designed through partnerships between system and component suppliers. Magneti Marelli has teamed up with Murata Electronics North America, using its EVC multilayer monolithic ceramic capacitors. At 1.3 x 1.6 x 0.1 in (33 x 41 x 2.6 mm), the capacitors are small enough to fit in locations that don’t impact balance. They can withstand up to 5 g, a critical factor in racing.
McLaren Electronic Systems has teamed up with Freescale Semiconductor, estimating that its use of KERS could yield an improvement of up to 0.4 s/lap. That could be realized by using a “boost” button to release stored kinetic power when the driver is overtaking a rival, for example.
Freescale engineers have joined their counterparts at the McLaren Technology Centre to develop technology that will be used in McLaren F1 cars that race during the 2010 season. Freescale will provide skills in motor control, microcontroller, and power systems. The team will also develop solutions for monitoring and controlling the battery subsystem that stores kinetic energy.