GKN’s plug-and-play electric tech
British engineering firm GKN Automotive offers off-theshelf solutions for car makers worldwide that are looking to electrify their fleets. We sample their cutting-edge tech
“We do our traditional tests on the drive system here, so how the system works on ice and also the lubrication” ANDREAS MAIR Director of product tech, GKN
IF Government statements are to be believed, there will only be 15 years of petrol, diesel and hybrid-engined new car sales in the UK before they are banned, leaving electric cars – and any potential hydrogen cars – as the only option.
Car manufacturers know this, but finding cost-effective and practical methods of electrifying their model ranges is a lengthy process that demands huge amounts of financial resources, as well as development time.
But what if someone else could do all that hard work? After all, manufacturers aren’t averse to outsourcing the building of new cars to third-party companies – just witness Austrian firm Magna Steyr, which builds numerous cars, including the Toyota Supra and Jaguar I-Pace, leaving each manufacturer to concentrate on other matters.
Could the same approach work for electric drivetrains? After all, there are arguably far fewer differences between electric motors than there are between internal combustion engines. So why not let a third-party company design your electric motors and EV control modules, which you, as a manufacturer, can then slot into whichever car you like?
Evolved
That’s exactly the proposition GKN Automotive has for car makers. From its roots in the Industrial Revolution as an ironworks making cannonballs during the Napoleonic Wars, this UK-based firm has evolved over the centuries to become one of the world’s leading automotive suppliers. Around half of all new cars sold today contain some sort technology that has been developed by the company.
GKN has read the motoring landscape wisely, and in 2002 introduced eDrive – a selection of hybrid and electric powertrains available for car makers to buy on a ‘plug-and-go’ basis. By 2025 the firm says it will produce one million eDrive units – more than it made in the past 18 years combined.
To find out what makes GKN’s eDrive such a compelling proposition for car makers, we visited the Colmis Proving Ground near the town of Arjeplog in northern Sweden, which has been the site of GKN’s Wintertest event since 1988.
Wintertest is a programme of cold-weather testing that sees cars and engineering technologies put through their paces in temperatures as low as minus 40-degrees Celsius. The test tracks at Colmis, meanwhile, sit atop a frozen lake, allowing GKN’s engineers to ensure their designs operate as they should in the extreme cold.
Dr Rainer Link, GKN’s vice president of engineering, explained to us how the firm works with car makers: “We demonstrate the products to the manufacturers and they think about what they can use in their cars,” he said. “Then, we come together and develop it in accordance with the final customer requirements, because every customer wants some small differences.”
At Wintertest 2020, the product GKN was most keen to showcase was its G400 modular eDrive system. Offering 169bhp and 410Nm of torque, it’s designed to be used as the primary drivetrain in mid-sized pure EVs, or as the secondary drivetrain in large hybrid vehicles. To show us what the G400 can do, GKN had fitted it to two demonstrator vehicles – a Tesla Model 3 and a Fiat Ducato passenger van – both of which we had the chance to drive.
While the Tesla didn’t pack the same punch as the standard Model 3 Performance, the power delivery was as smooth as one would expect from any series production car. The Ducato wasn’t quite as refined, however, because the engineering team hadn’t had the time to put the
“We demonstrate the products to the manufacturers and they think about what they can use”
drivetrain under the bonnet, so it was mounted behind the driver’s seat. But it still had enough pull to comfortably move the van; impressive when you consider the size and weight of the Ducato, and the fact the drivetrain was powering its front wheels, when the G400 unit is designed to be used in a rear-wheel-drive set-up.
The G400 also has a few tricks up its sleeve, which GKN claims puts it ahead of some of the electric drive systems that car makers might produce themselves. One of these is oscillation control, which is designed to prevent the slight juddering that EVs can experience when drivers pull away at super-low speeds. We tried it out by stopping the Model 3 halfway up a steep hill and then moving off again, once with the system on and once with it off. While it was a subtle improvement, it certainly made things smoother.
Aside from smaller (G250) and large (G500) versions of the G400 unit, another key product for GKN is its Twinster set-up. Fitted to everything from the Ford Focus RS to the Range Rover Evoque, the Twinster is an off-the-shelf four-wheel-drive system that’s able to react to both the driving environment and the driver’s intentions, modulating clutches and torque loads to each or both sides of the car when needed. One of GKN’s professional drivers took us out for a ‘taxi ride’ around Colmis’ handling circuit in an Opel Insignia Sports Tourer fitted with Twinster, to show us what it could do.
Controlled
The track had been used a lot throughout the day by this point, meaning the ice had become polished and slippery. Nevertheless, our driver was able to take each corner at well over 60mph, approaching each one sideways and still coming out without incident. On some he was even putting the car into a controlled spin, rotating it 90 degrees left and right without spinning out.
But what happens when you combine the Twinster fourwheel-drive powertrain with GKN’s modular eDrive system? Well, that’s exactly what the firm sought to answer when it created its eTwinster, which GKN describes as “the world’s most advanced electrified vehicle technology”.
The prototype package had been fitted to a
Jeep Renegade running the G250C modular electric drivetrain, but in conjunction with the twin-clutch Twinster torque-vectoring system and GKN’s unique two-speed eTransmission. Many electric cars on the market today use a single-speed transmission, but GKN is betting manufacturers will move to multi-gear systems in the future, claiming that such a configuration gives a better balance of acceleration and top speed than single-speed units, and can also improve battery range.
From behind the wheel, the difference made by the eTransmission quickly becomes apparent. First gear allows the car to use the instant torque that anyone who has driven a modern electric car will be familiar with, but once you’re going fast enough, there’s a noticeable change as it selects second gear. GKN’s two-speed transmission made its production debut in the BMW i8 in 2013, but the package combining it with eTwinster has yet to appear in a production car – although the firm says it’s ready for pilot production for any interested manufacturers.
Speaking to Andreas Mair, GKN’s director of product technology, we asked him what challenges cold weather brings for electric cars. “On the drive system itself, it’s our more traditional tests which we are doing here, so how the system is controlled on ice and also the liquids – lubrication viscosity is increasing quite a lot up to -40C,” he said. “In general, we go into Wintertest not just because it’s cold – all of our devices have to live between -50C and +50C. The reason we do Wintertest is because, on ice, you can feel how we bring the torque to the wheels, and how stable the car is.”
On the surface, it looks like some manufacturers might struggle to electrify their model ranges by 2035. But with GKN’s electric vehicle technologies readily available to them, do they really have any excuse not to hit the target?
Our time in Arjeplog showed that off-the-shelf units such as GKN’s could provide an easy answer for manufacturers looking to electrify their ranges quickly, although there was one shortcoming that even a firm as sophisticated as GKN can’t solve, Dr Rainer Link told us separately: “Battery capacity is dropping significantly due to the cold temperatures – at -40C we lose about half. But that’s not our main focus, because we don’t supply batteries.”
“We do Wintertest because, on ice, you can feel how we bring the torque to the wheels, and how stable the car is” ANDREAS MAIR Director of product tech, GKN