The Tesla Model S is the latest EV involved in a benchmarking tear-down by Ricardo Strategic Consulting. It will also be the first vehicle to undergo performance testing by Ricardo’s EV benchmarking study consortium. Ricardo engineers will be putting the Model S on the track to capture its performance characteristics before meticulously disassembling the vehicle to study its components.
When completed in early 2014, Ricardo’s benchmarking study will allow automotive engineers, designers, and manufacturers to take a virtual tour around the inner-workings of the Tesla vehicle. They will be able to examine and measure how components work together. They will also have access to precise measurements, specifications and a level of detail only available to the original vehicle designers.
Ricardo created the benchmarking study consortium two years ago to give automotive industry professionals an in-depth look at electric vehicles. Their innovative tear-down technology provides web-based access to the most detailed information available about how a vehicle works, says Scott Ellsworth, Ricardo’s managing director, North America.
Ricardo is a global provider of strategic consulting and product innovation and engineering solutions. The program is a natural fit for the company, “driven by our own internal curiosity into what evolving vehicle systems look like and how they will change in coming years,” says Ellsworth. Eight vehicles have been analyzed by Ricardo engineers during only two years of benchmarking. The Tesla Model S benchmarking provides unique opportunities for both the Ricardo tear-down team and participants in the consortium. “We are very interested in how Tesla’s approach and supply chain is different, and how these technologies will change and mature if there is a consolidation in providers.”
Why the Tesla Model S
The Tesla Model S – along with the Nissan Leaf EV and Mitsubishi iMiev – are unique benchmarks to which all other EVs will be compared in the coming years. Since the first Model S cars were shown in North America in 2012, they have created a buzz with both automakers and consumers. The car has received numerous awards and recognitions, including the 2013 Motor Trend Car of the Year, 2013 World Green Car of the Year, Automobile Magazine’s 2013 Car of the Year, and Consumer Reports’ top scoring car ever. It is already the world’s highest production volume EV that has an induction motor powertrain – and it is on track to ship over 20,000 units in 2013.
As Jean Jennings, the editor-in-chief of Automobile Magazine put it, “It’s the performance that won us over.” The Tesla Model S can accelerate to 60 mph in 4.3 seconds. It has a three-phase, four-pole AC induction motor with copper rotor and lithium-ion battery options spanning 60-85 kWh. With the larger battery size, the car has a range of more than 200-miles.
Induction vs. Permanent Magnet Motors
Ellsworth finds comparisons between induction and permanent magnet motors particularly interesting. “As the market sorts out the preferred technologies and the cost-effective technologies, we want to make sure we are capturing the breadth of motors that are becoming production-inclusive today,” he says.
Testing the performance and efficiency of the driveline, motor and inverter systems in the Tesla Model S is a priority for Ricardo. “Benchmarking motor and inverter efficiency is a key task,” Ellsworth says. “How does the motor’s performance change in different temperature regimes and with different load cycles and states of charge?”
There is industry concern that the permanent magnet motor architecture in other, non-Tesla vehicles relies on the high cost and cost-volatility of rare earth metals. “The induction motor does not require that kind of risk or cost aspect, and that’s beneficial for automakers,” Ellsworth says. The permanent magnet motor does have some technical performance advantages that keep it on the radar screens of vehicle designers. “I think the reason the permanent magnet motor has gained popularity is its often high power density and efficiency,” adds Ellsworth.
Ricardo’s Benchmarking Study Consortium: A Cost-Effective Business Model
With the strong interest the Model S has generated – and its relatively high cost – a $62,500 base price – it is not surprising that automakers, powertrain engineers, motor suppliers, and vehicle marketing teams are joining Ricardo’s consortium. According to Ellsworth, “there has been a significant amount of outstanding publicity for the vehicle. However, from a business standpoint, it is a very expensive vehicle for many of our clients to obtain themselves. With Ricardo doing the tear-down, we can cost-share the price of this vehicle with interested subscribers.”
Providing the study results in an interactive web-based format gives subscribers easy access to the information from locations throughout the world. “For example, a team in India can look at the report as easily as teams in France and the U.S.” says Ellsworth. This proven presentation format allows subscribers to see in-process photography, where they can review components at all angles and aspects. Participants can capture the weight and the manufacturing details of a battery cell. They can also see how that cell sits in the battery module and the battery pack in the vehicle,” adds Ellsworth. This is in addition to seeing how components fit together and perform in sub-systems that provide, for example, cooling or power control.
“It’s our job to provide an independent, informed and comprehensive view of this specialty market. We are not commenting on what OEMs have done correctly or incorrectly,” says Ellsworth. We don’t have an agenda, and that’s respected by our customers.”
Vehicle engineers around the world eagerly await the results of Ricardo’s benchmarking study on Tesla’s Model S and what it will say about its mass-produced induction-motor-based powertrain.