Flybrid Mechanical Hybrid System Powering Dyson Racing Prototype at 10 Hour Race on Saturday
by Robert Kozak (Advanced Biofuels USA) Hybrid energy storage systems will play some part in the effort to meet the new 54.5 mpg CAFE standards. Their importance will be dictated by their weight and efficiency. We thought you’d be interested in a lightweight alternative to the electric battery that is being tested this week at Road Atlanta.
This Saturday at the 10 Hour Petit Le Mans road race, Dyson Racing will be using a new mechanical hybrid energy storage system in their #16 Lola Mazda prototype. While most people think of electric motors and batteries when they hear the term hybrid energy storage, the system selected by Dyson racing is completely different.
The mechanical system, which is being developed by a British company Flybrid Automotive Limited, www.flybrid.co.uk is a lightweight unit that is located in-line between the race car engine and the transmission.
As in all vehicle energy storage systems, kinetic energy of the vehicle is captured when the vehicle is slowing down and released when the vehicle accelerates. The advantage of the Flybrid mechanical system, also called a KERS (Kinetic Energy Recovery System), is its simplicity as compared to an electrical battery system. Kinetic energy is directly transmitted to the flywheel, which spins up to 60,000 rpm, and released back as torque through the existing transmission of the vehicle (Figure 1).
Figure 1: Flybrid Energy Storage System
Figure 2: Electrical Energy Storage System: Simplified Design
In comparison, an electrical energy storage system requires at least one electrical generator/motor and a battery pack (Figure 2). Without these additional components the Flybrid system weighs only 80 lbs. A comparable electrical storage system would weigh about 2.5 times or approximately 200 lbs.
In the Dyson Racing Team garage at Road Atlanta, we spoke with Tobias Knichel, Commercial Manager of Flybrid about the design of the system, its commercial potential, and why they have chosen “Green Racing” for product development.
The Flybrid system used in the Dyson racer is not specifically built for that car but is instead a prototype 100 KW (134 hp) unit that is sized for a number of different racing or road going vehicles.
Tobias explained this is possible because total captured kinetic energy is produced by the speed and mass of a vehicle. So, while a racing vehicle like the Dyson Lola may be stopped from 180 mph it weighs considerably less than a ton (2,000 lbs). On the other hand while a SUV may be stopping from only 70 mph, it may weigh 2.5 tons (5,000 lb) loaded. Therefore, Tobias said, by adjusting the clutches and the gear ratios in the Flybrid system, the same unit could be used in everything from a race car to a city bus.
In addition, the design of the flywheel can be optimized for capturing inertia energy by adjusting its proportions to the braking rate of the target vehicle. Basically, a vehicle with a slower braking rate requires a flywheel that can spin up quickly with little energy input because the stopping power of the vehicle is lower.
Flybrid is currently working with both car and bus manufacturers on the commercial use of their KERS system. Jaguar is among a number of companies that have prototype units installed in test vehicles.
On the bus side, they are developing the units to be retrofitted into existing English diesel powered city buses. One version combines two flywheel units that feed into one 100kW clutch/transmission unit.
We asked Tobias why Flybrid was so involved with racing. He pointed out that racing miles are much more stressful on equipment than road miles, about 10 times as much per mile. Therefore, for Flybrid this allows them to greatly shorten their development cycles. He said this was important since they have set 2016 as their goal for having units in fully-warranted production vehicles.
We later spoke with Chris Dyson who drives the #16 racer and is deeply involved in the operation of the family-owned race team. He said Dyson Racing is using the Flybrid system to not only win races but also to show the importance that racing can have for all automotive development.
Dyson said they are happy to be on the edge of testing this new technology. “We’re hot-rodders after all,” he said.
Dyson emphasized that use of the Flybrid is not just a three-race deal. It will be in their racers in 2013 and for them it’s a long-term commitment to the future of automotive technology.
As for the research and development of the Flybrid system, the first race at Virginia International Raceway (VIR) in September was not successful. Dyson said Flybrid’s dynamometer simulation was not able to model some situations encountered at VIR. However, he said, Flybrid responded quickly. The changes have been made and they are optimistic for Saturday’s race. (They were second fastest in practice on Thursday.)
The fact that Dyson Racing is at the forefront of developing this mechanical hybrid system in long duration road races should not be a surprise to followers of Green Racing. Dyson Racing introduced the advanced biofuel bio-isobutanol to racing in 2009 and won the first race on that fuel in 2010 at Mid-Ohio. Unlike other hybrid systems, Flybrid’s works with any fuel from bio-isobutanol to diesel, renewable diesel and biodiesel, to high blends of ethanol.
The 1,000 mile Petit Le Mans starts at 11:30 am on Saturday, October 20th. Check www.alms.com for details. Photos: J.Ivancic
Technical corrections regarding kinetic and inertia energy made 10/20/2012 1:20