Knowing exactly when to use power during a race, and when to make the best use of energy recovery through regenerative braking is essential to getting the best performance from the Jaguar I-TYPE 5 Formula E race car. Efficiency wins races.
Jaguar TCS Racing drivers Mitch Evans and Sam Bird expertly judge lap after lap where the optimal braking point is for a corner, but just as importantly the best place to lift off the accelerator, enabling them to maximise regen and not waste energy using the friction brakes. Learning from these strategies has direct real-world customer benefits through enhancing efficiency and reducing emissions for Jaguar’s plug-in electric hybrids (PHEVs) and mild-hybrids (MHEVs).
In preparation for each round of the ABB FIA Formula E World championship, the Jaguar TCS Racing team creates a highly detailed model of every city circuit right down to drainage covers – the one created for the London e-Prix, taking place 30-31 July, also reflects the changes made for this season to the curvature of the double chicane between turns 10 and 13. The models are used in the state-of-the-art driver-in-the-loop simulator to develop the energy strategies for the races.
These race-winning strategies ensure that the drivers always press the accelerator – and lift off – at the optimal time, enabling them to conserve as much energy as possible.
This capability ensures that every joule of energy sent to power the I-TYPE 5’s motor – and returned to charge the battery during regenerative braking – is accounted for and used as efficiently as possible. Mitch and Sam fully exploit the performance needed to stay in front while ensuring they have enough energy to get them to the chequered flag.
Software learnings from this process helped in the development of the Predictive Energy Optimisation function for the Jaguar F-PACE P400e and E-PACE P300e PHEV models. Entering a destination into the Pivi Pro infotainment system’s navigation gives PEO an overview of your journey (out to a maximum of 650km) which it splits into 100-metre segments for analysis.
Taking in a wealth of GPS map data including the types of roads – and average speeds on them, together with gradients – PEO makes an informed decision on how best the powertrain should be used at each stage: prioritising the electric motor in urban areas to deliver zero tailpipe emissions driving, for example, or the efficient Ingenium petrol engine on motorways. This intelligent, predictive control of the two power sources can improve energy efficiency in real-world driving by up to 10 per cent*.
The system also ensures that you have at least six kilometres of EV range in reserve, ready for deployment in the final stage of your journey and enabling you arrive at your destination silently and with zero tailpipe emissions.
In addition, the Eco Coach feature – found in the Jaguar XE, XF, E-PACE and F-PACE MHEVs – uses intelligent algorithms to help customers develop a smoother, more efficient driving style by reading the road ahead and prompting them when to lift off, maximising the benefits of regenerative braking. Eco Coach technology is comparable to the lift and coast cycles that Mitch Evans and Sam Bird use to optimise energy usage during an E-Prix. Regen is fundamental in Formula E as the race cars regen around a third of the energy required to complete the race distance of 45 minutes plus one lap.
On the road, Eco Coach uses the vehicle’s GPS location and data held in the cloud to anticipate the most likely route that the vehicle will take. Together with map data including gradients, road curvature and speed limits, the technology can look ahead for up to 2.5km – the so-called electronic horizon – to understand upcoming road features such as corners, junctions and roundabouts, lower speed limits and downhill slopes – all elements that would likely result in the driver backing off the accelerator pedal.
Updated every 10-metres, this intelligent picture of the road ahead is sent to the powertrain control module to determine the optimal point for the driver to lift off, enabling as much deceleration as possible to be done by regenerative braking instead of the friction brakes.
When the vehicle reaches this point, Eco Coach intuitively prompts the driver to take their foot off the accelerator by displaying a filled-in green pedal icon in the instrument panel, which changes to an outline when they do so, and then disappears if they apply the brakes. This replicates the steering wheel light system the race drivers use to know when to lift and coast on the race track.
James Barclay, Jaguar TCS Racing Team Principal, said: “The difference between winning and losing can be down to less than one percentage point of energy consumption per lap – every marginal gain we can make to efficiency makes a difference. That’s why we model each circuit – and the Jaguar I-TYPE’s performance on it – to such a fine level of detail so that we develop the optimal energy strategy for every Formula E race.
“The techniques we use and the invaluable knowledge we’ve built up has helped to make the Predictive Energy Optimisation technology in Jaguar’s plug-in hybrids so effective and enables customers to get the most from their state-of-the-art powertrains. The same applies to the Eco Coach technology in Jaguar’s mild-hybrids, helping drivers to save fuel and reduce emissions. Both are great examples of our Race to Innovate philosophy and how we are bringing our learnings from highly competitive world championship motorsport to our customers.”
*Article Source http://newsroom.jaguarlandrover.com/en-gb/jaguar/