Continental presents 48V full-hybrid system; motor delivers up to 30 kW
02 July 2019
Continental has been developing cost-effective 48-volt electrification, which can be used with both gasoline and diesel engines for number of years. In the run-up to IAA 2019, Continental Powertrain is now presenting a 48-volt high-power drive system with 30 kW, enabling a full-hybrid vehicle.
Conventional full-hybrid vehicle would normally use high voltage technology. The Continental 48-volt hybrid system that offers features similar to those of a high-voltage electric drive.
The new 48-volt high-power system, comprising an electric motor with integrated power electronics and a battery, reduces fuel consumption and thereby also CO2 emissions by around 20% compared with similar vehicles fitted with combustion engines. At the same time, the new 48-volt technology is also considerably cheaper than the high-voltage systems used up to now.
Our development objective was to achieve a level of driving efficiency with 48-volt technology that was previously reserved for high-voltage systems and we have now done exactly that.
—Stephan Rebhan, head of Technology & Innovation at Powertrain
The 48-volt systems were previously known as mild or P0 hybrids. They involve relatively unobtrusive electrification of the powertrain. Fuel consumption is reduced mainly with the support of the combustion engine (boosting) during acceleration and the recovery of excess kinetic energy (recuperation) when the vehicle decelerates. However, purely electric driving is not possible with such systems, which Continental already manufactures for a number of automotive manufacturers.
In the latest stage of development, the 48-volt system was repositioned in the powertrain. The electric motor was no longer placed in front of the combustion engine on the crankshaft, but behind it—between the combustion engine and transmission (P2 hybrid). This meant that fuel savings were able to increase and, in certain situations, such as driving through a 30 km/h speed limit zone, the vehicle could be driven using the electric motor alone.
With the new 48-volt high-power technology, this hybrid system enables the same functionality as previous, full-hybrid vehicles. The key component here is a new, water-cooled electric motor, the peak output of which was doubled to 30 kW in comparison with that used previously. Electric-only driving is therefore possible up to a speed range of 80 to 90 km/h.
48-volt high-power electric motor with a peak output of 30 kW.
The developers were able to achieve a 100% increase in power while maintaining the diameter of the motor. Overall, 48-volt high-power technology requires only slightly more installation space than the previous system. The difference in weight is also minimal.
However, the electric motor is not the only new component of the 48-volt high-power technology. The integrated power electronics also uses a new technology that now enables it to handle significantly higher currents. The innovations of the new 48-volt high-power technology result in a level of electrical efficiency that surpasses the previous system by almost 10%.
During recuperation, the new technology is much more effective than was previously the case because the losses incurred in the electric drive system has been halved.
A 48-volt system requires considerably less effort in terms of insulation protection, electrical components are smaller and cheaper, and even the design can be made significantly more compact, because smaller gaps are required between the individual components than is the case with high-voltage technology.
Continental is showcasing the new 48-volt high-power technology, which is also ready for series development, in a Ford Focus test vehicle.
With an eye on the new approval regulations that have been in force since 1 Septembe 2018, in accordance with the WLTP cycle, the 48-volt high-power technology could be developed even further. If, for example, the system was supplemented by on-board charging technology and a larger battery, this would make even a plug-in hybrid drive featuring 48-volt technology possible. This is because the ability to drive in all-electric mode is no longer the main criterion for benefiting from the support for plug-in vehicles. Instead, it is the conversion of electrically stored energy into traction in general.
The deciding factor for different funding initiatives is whether CO2 emissions can be reduced to below 50 g per kilometer.
8-volt high-power electric motor...
I think they meant 48.
Posted by: SJC | 02 July 2019 at 09:02 AM
IMO Toyota are likely to be far more concerned by the challenge to their hybrids from 48Volt lower cost cars than they are about other's BEV offerings.
Posted by: Davemart | 02 July 2019 at 10:37 AM
Great to see this. Hopefully they'll be able to get this into loads of cars at reasonable cost ( say +1K to the driver)
Then improve it further.
The new Eu 95 gms/km ruling might accelerate the uptake.
(Will not might).
Posted by: mahonj | 02 July 2019 at 11:31 AM
Battery development and battery cost reduction are the main factors holding back BEV growth in the markets. In time these interim, complicated solutions, i.e., all forms of hybrids, will not be needed.
Posted by: Lad | 02 July 2019 at 12:55 PM
trying to figure how this fits between engine and trans? the usual P2 arragement is a disk on flywheel arrangement so this is belt drive? something makes little sense.
Posted by: Arnold | 02 July 2019 at 04:56 PM
30kw/48V=625 AMPS! There must be a lot of batteries in parallel or supercaps, and beefy wires!
Posted by: GdB | 02 July 2019 at 10:31 PM
Ouch, those Amps are huge, if the battery is in the back and motor in front, what kind of cable will you need?
Are those high voltage orange cables really that more expensive?
I'm a little puzzled, Toyota has run the cost down so much, that the price of their hybrids are getting in the "normal price" region. No matter how much this "bolt on" system costs it already costs too much. The right way of hybridisation is engine and transmission simplification. I don't know how this 3rd party "bolt on" solution will survive, a full hybrid drivetrain should be made from the ground up, IMO the only way to keep costs low.
Posted by: GasperG | 03 July 2019 at 12:15 AM
@GasperG
This will cost less than Toyota's hybrid system. Definitely! Why should there be no room for an intermediate solution on the cost-benefit scale? Where did you get the idea that this is a "3rd party solution"? Continental is one of the biggest suppliers to the automotive industry. They are definitely a Tier 1 supplier to the industry. For sure, they are developing this together with a couple of car manufacturers, like all other vehicle components. Oftentimes these days, development is actually initiated by the suppliers, not by the car manufacturers.
Posted by: Peter_XX | 03 July 2019 at 01:16 AM
The problem is that supplier is developing more or less this on it's own and trying to sell it to manufacturers. The manufacturer then assembles all the parts as Lego blocks, so the additional cost of the hybrid system is directly the additional cost of the end product. Building the full hybrid system from the ground up (Toyota, Honda, Renault...) can result in the cost saving elsewhere, for eg. transmission. Instead of transmission there are some simple gears, but of course you then need two MGs.
You save on the mechanical cost and complexity but you add value through higher cost of electric part. In the end you end up in similar price range, even if full hybrid cost a little more it also offers more and is more reliable (less moving parts). The consumer will have the last saying and I think the consumer can value and chose the superior technology even if it costs 5% more.
Posted by: GasperG | 03 July 2019 at 03:12 AM
625 amps is in the ballpark for a conventional 12 volt starter motor, so the cables would be about the same as today's battery cables. Probably need better cooling, though; they'd be used a lot more.
Posted by: Engineer-Poet | 03 July 2019 at 07:00 AM
This development may interest auto companies to make all LDV hybrids. In 2012 Mercedes Benz can out with the E300 Bluetec Hybrid which had a 20 kW motor and it did a good job in a large diesel sedan (I think Peter_XX has said that diesel hybrids would do well and a low cost version would be outstanding).
Since auto companies are moving to 48V systems to power electric air-conditioner compressors, power steering, and other accessories this should be a near zero cost addition (also note this replaces the starter motor and alternator as well), with the exception of the battery. So the real cost is going from a 500 Wh battery to a 1.25 kWh battery (48 V and 25 Ah).
Finally, this is a 3 phase AC motor, not DC (check here on page 9 ), so amps are more like 360 not 625.
Posted by: Account Deleted | 03 July 2019 at 09:43 AM
They don't make 3φ batteries. The power is only AC between the inverters and the motor windings. Between the inverters and battery, it's DC.
FYI 3φ power is measured by voltage line-to-line but current in each phase. This lets you multiply voltage by current and get power without having to mess with factors of 3. It's also why you have funny voltages like 277 VAC in commercial and industrial settings; it's the phase-to-ground voltage of a 480 V 3φ line.
Posted by: Engineer-Poet | 03 July 2019 at 11:49 AM
That's correct. Checked out electricmotorsport.com and they have controllers (and induction motors) that handle 650 amps at 48 volts, so 625 is no problem.
Posted by: Account Deleted | 03 July 2019 at 12:04 PM
For comparison, here are the details of the Punch Powertrain 48Volt systems which the PSA group will install:
https://www.punchpowertrain.com/en/products/27/dt2-48v-phev#formspec
As always, they are looking for a cost effective solution, which comes in under the Continental one for efficiency, but is good for part count etc.
That is going into a lot of cars in Europe in the next few years.
Posted by: Davemart | 04 July 2019 at 10:47 AM
Oooh, that's another good one! The industry shift is obvious.
Posted by: Engineer-Poet | 04 July 2019 at 11:04 AM
Valeo also has shown a 48 Volt PHEV here.
You could even add more power than the 30 kW Continental 48V by using a Boost Converter like Toyota does on their hybrids.
Posted by: Account Deleted | 04 July 2019 at 12:32 PM
Gryf:
Apparently the dual clutch Punchpowertrain:
'48V or PHEV variants
The unit can be either equipped with a 48 Volt low power motor (20kW), or with a high voltage powerful electric machine (90kW), without any design changes to the base transmission.
The 48V solution equips mild hybrid electric vehicles (MHEV), resulting in a fuel saving of up to 15%, while the high voltage solution is designed for plug-in hybrid electric vehicles (PHEV), with up to 75% of fuel savings.
Flexible hybrid fleet
This flexibility in electric power level - and thus cost - is unseen for any other transmission, currently on the market. Such easy scalability of cost is important, because it enables OEMs to continuously adjust their vehicle fleet electrification mix to the market demand and ensure compliance with CO2-mandates. In this mix, also non-hybrid DT2 transmissions (without electric motor) still holds an important position.'
(ibid)
Posted by: Davemart | 04 July 2019 at 12:44 PM
Davemart:
The Punchpowertrain does look interesting and like the new ZF 8HP automatic transmission makes converting a vehicle to a hybrid or PHEV relatively easy (BMW and FCA use the ZF 8HP in their current and future PHEV).
My only concern is that a low cost option would make widespread adoption possible.
Both Toyota and Honda have been able to do well by making their hybrid and PHEV vehicles by leveraging their original investments. Though others particularly GM have moved away from PHEV.
Posted by: Account Deleted | 04 July 2019 at 01:51 PM
Gryf:
'My only concern is that a low cost option would make widespread adoption possible.'
? Why is that a concern not an advantage?
Posted by: Davemart | 05 July 2019 at 02:30 AM
Corrected:
My concern is that only a low cost option would make widespread adoption possible.
Posted by: Account Deleted | 05 July 2019 at 07:38 AM
That depends how much it lowers the TCO, does it not?
There's the additional factor of the used market. People who purchase new and/or lease tend to spend more money, but they determine what vehicles are available as used a few years down the line. (People like me who drive their new cars into the ground are the exception.) If hybrids become a larger part of the new-car fleet, they're going to start winding up in the hands of people who can't afford new cars in just a few years. The level of adoption will far exceed the level of those who can afford to buy them new.
Posted by: Engineer-Poet | 06 July 2019 at 10:33 AM
Regarding the thick cables needed for 600 Amp DC currents, here are some statements from a document on 48V from site Zwei.org. "There is a common ground for the 12/24-volt system and the 48-volt system, which are connected via physically separate rounding bolts/connections.". Also "no isolated grounding (B-) required". It means that for negative, i.e. ground, a thick aluminum rail can be used, which is half the weight (compared with a copper conductor of same ampacity), and cheaper than copper. That Alu rail wouldn't need to be isolated from the chassis. Copper cables (or rail) can be attached to Alu rail via bimetal washers (Alu with deposited layer of Cu) and bolts. It can be considered dry environment (for Alu-co connection).
For HV systems, both positive and negative battery cables (to inverter(s)) need to be isolated.
I read in a study done by UBS that HV isolation costs more than $1,000 per car for a PHEV.
For PHEVs with 2 or 3 traction e-motors (AWD system) it may make sense to use 48V system, with these 30 kW motors, to reduce costs. Even better if some of the used e-motors are paired with multi-speed transmission. Hyundai Sonata, 1st gen. PHEV used 50 kW e-motor with transmission (P2 system).
Posted by: Alex_C | 08 July 2019 at 03:49 PM