Global drivetrain manufacturer Dana has been developing a range of hybrid and fully electric power solutions over the past 20 years. Dana’s Director of Global Product Planning, Steve Slesinski, spoke to Prime Mover about the company’s current and future electrification strategies.
With a history in driveline system innovation reaching back more than 115 years, it’s hardly surprising that Dana has accurately predicted the steady swing towards electric vehicles (EV) and is accordingly well advanced in the development of numerous systems within the electrification sphere. This is necessary to ensure the meeting of demand for electric vehicles, which might account for, according to current predictions, roughly 30 per cent of the overall global vehicle market by 2040.
Having a presence in 33 countries including 23 global technology centres and 140 major facilities, Dana employs more than 30,000 people and has in excess of 10,000 customers across 140 countries. Unlike conventional engine manufacturers facing the complete substitution of their hardware with electric motors, Dana has a significantly more eclectic suite of product offerings, much of which is eminently compatible with EV and hybrid applications.
For example, with many hybrid and fully electric vehicles the conventional differential and rear axle assembly is retained to transmit drive from the engine and/or electric motor to the road wheels.
Yet even this is changing for certain applications as Dana engineers work on ways of integrating electric motors with axles to provide a direct motor drive.
As Dana’s Steve Slesinski points out, the company is currently working on a broad range of electrification solutions, some of which are transitional or interim measures which support and enhance the traditional internal combustion platform by allowing it to operate more fuel efficiently.
But before exploring these, it was significant to discover the number of EV powertrains Dana has already supplied to the global market.
“We have already produced drivelines with centrally-mounted electric motors and inverters for well over 13,000 vehicles globally,” Steve says.
“In addition to that we are working on more advanced solutions that include not only central drive configurations but also the integration of drive motors into axles for specific applications.”
Steve explains that the primary focus for this advanced technology is the pickup and delivery (PUD) market where the vehicles generally travel at much lower road speeds than over-the-road or linehaul vehicles.
Furthermore, the typical stop-start operation provides battery regeneration every time the vehicle slows or stops. He acknowledges that while a large proportion of buses in China are powered by Dana electric drive systems largely due to financial incentives provided by the Chinese government to encourage uptake, the use of electric drive technology is close to becoming financially viable in its own right in some applications.
“We’re at the stage now where there’s probably a viable business case for fully electrified propulsion systems as replacements for conventional propulsion systems in PUD roles,” Steve says.
He proceeds to explain that while some electric drivetrains are retrofitted to conventionally powered vehicles, this is not ideal because of the waste involved with removing the various components that aren’t needed anymore.
He says it is far more efficient to use ‘gliders’ – conventional vehicles without any powertrain related components installed – or vehicles purpose-built from the ground up with electric propulsion.
Asked his view on EV uptake over the next 20 years, Steve says he would not be surprised if an average of 30 per cent of the world’s vehicles are either battery or hydrogen fuel cell electric powered by 2040.
He is quick to add that market segment percentages will vary widely due to differing degrees of suitability for EV use in various vocations.
“With the likes of refuse collection and yard tractor applications it could be as high as 80 per cent by then,” he says. “On the other hand, with typical on-highway trucks travelling long distances the percentage will be much lower, and there will more than likely be different forms of hybrid power and fuel cell technology rather than full battery electric.”
Unpacking this concept further, Steve mentions that there are numerous ways electric power can be used to assist the primary diesel engine and therefore lower fuel consumption of trucks.
“Wheel-end motors are great for relatively low speed operation and this is one of the methods we use for our off-highway hybrid systems,” he says.
Another variation of the hybrid concept for tandem drive prime movers has been the lead or forward axle powered by a diesel engine while the tag axle incorporates a centre axle mounted electric drive motor which assists from a standing start and when climbing grades, thereby reducing fuel consumption. The electric drive axle also doubles as a highly effective retarder and battery charger on descents and when the vehicle is brought to a halt.
“If you factor in that it can also provide hotelling or auxiliary power unit (APU) capabilities while the truck is stationary, this system can generate upwards of 25 per cent efficiency gains in linehaul applications,” Steve says, noting that it uses a 7.0kWh lithium titanate battery pack designed for rapid charge and discharge events over a lengthy duty cycle.
“With a full battery pack charge you can run the cab climate control, TV, coffee machine, microwave, internet for a full ten hours before needing to recharge,” he says.
In yet another take on the hybrid theme, Dana is also developing electrification for vehicle ancillaries including air conditioning and braking system air compressors as well as power steering pumps.
“In January this year Dana acquired SME Group, a European-based electric motor and inverter manufacturer,” Steve says. “SME provides low-voltage motors that can be used to power ancillary systems on vehicles. Electrifying a hydraulic power steering system, for example, takes the parasite load off the engine and only switches on when it’s needed.”
In terms of a linehaul prime mover potentially travelling for hours in virtually a straight line with no need for power assisted steering, it’s not hard to see how this innovation would save fuel.
“We’ve achieved fuel saving in the order of two to three percent during tests on linehaul vehicles fitted with electric power steering,” Steve says. “Taking the load of operating the ancillaries off the engine could also enable the engine to be downsized for even better fuel efficiency.”
In summing up, Steve says the message Dana wants to impart is that fully electric vehicles are but one aspect of the multi-facetted electrification equation.
“It’s not feasible to have fully electric vehicles across the board at this stage because primarily we don’t have the grid power necessary to charge them all,” he says. “What Dana aims to achieve is a range of targeted electrification solutions to suit specific applications. Installing electric power steering on linehaul vehicles and full electrification of refuse collection vehicles are two great examples of this strategy.”