Sudden invasion of "MildHybrids" ?

Hillhater

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In the past week or two, the press has been swamped with articles from several of the big auto makers .. Audi, VW, Volvo, Renault, ....about the 48v "Mild Hybrid" systems they will be incorperating on their cars in the near future. Some as early as 2018.
Most of these seem very similar systems, using 48v, belt drive, "Altermotor" units in place of the normal alternator and starter motors , coupled to the necessary controls and a small 1-3kWh Liion 48 v battery.
Power varies from 10 - 12 kW + and 60-70Nm of torque. (150-200 Nm at the crankshaft), with regen used to recharge the pack (not plug in)
These all seem very similar to the BAS system used in the US by GM on the Saturn etc a few years back, but it seems these latest systems are being produced by Continental, in Germany.
One suggestion is that it is a way to keep the Diesel engine clean enough to remain viable for a few more years when it is reprogramed to meet emissions legally.
Odd that they have all announced at the same time ?
 
Non plugin hybrids are a complete nonsense as they can only ever be powered by burning fossil fuels. IMO, they are a BS move to appear environmentally friendly to those who don't know better and only exist due to manufacturers hands being forced.
 
danielrlee said:
Non plugin hybrids are a complete nonsense as they can only ever be powered by burning fossil fuels. IMO, they are a BS move to appear environmentally friendly to those who don't know better and only exist due to manufacturers hands being forced.
Not true.
As someone who cannot afford a full EV, or PHEV, I instead bought a used Prius. It (like all hybrids of this type) charges primarily through regen braking. The battery pack is small and lightwieght as a result, but it still provides a significant contribution towards low fuel usage. In my case my 13 year old Prius with 285000+km on the clock can still manage 5L per 100km.

Cheers
 
They have the potential to make a big difference to local air pollution in congested urban areas: true stop-start facility for the ICE and the ability to run in EV mode when crawling along in slow traffic. In addition, the regen braking and assisted acceleration does significantly reduce fuel consumption in urban driving where the vehicle is constantly speeding up & slowing down.
 
as soon as a few of those 2018 get wrecked, those 48v packs will be going on ebikes!
 
Hillhater said:
They will/do certainly improve fuel consumption, but i do not see how they will recover much regen power without some major changes to the ICE, gearbox/clutch/torque converter operation.

It doesn't regen through the transmission. A load is put onto the belt-driven alternator/generator/starter device which puts a mechanical load on the motor directly. Only belting systems have to be modified to handle the loads.
 
danielrlee said:
Non plugin hybrids are a complete nonsense as they can only ever be powered by burning fossil fuels. IMO, they are a BS move to appear environmentally friendly to those who don't know better and only exist due to manufacturers hands being forced.
?? They make modern vehicles more fuel efficient, and also allow easier connection of high power accessories (active suspension, electric power steering, electric A/C etc.) Look for cars to start using this even if they don't want the efficiency - they will just want the power to drive new accessories.

BTW this isn't anything new. I bought my first mild hybrid 15 years ago.
They will/do certainly improve fuel consumption, but i do not see how they will recover much regen power without some major changes to the ICE, gearbox/clutch/torque converter operation.
By running as a generator with the engine in gear. Drag on the engine results in braking; it's how jake brakes on trucks work.
 
billvon said:
They will/do certainly improve fuel consumption, but i do not see how they will recover much regen power without some major changes to the ICE, gearbox/clutch/torque converter operation.
By running as a generator with the engine in gear. Drag on the engine results in braking; it's how jake brakes on trucks work.

Yes i understand, but the majority of cars are autos, mostly with torque converters, which tend not to "hook up" on overrun.
Even the clever dual clutch autos, would need to be especially configured/programmed to make the most of overrun energy.
A fully manual would be easiest, but that would still need the driver to consiously change behaviour to use regen rather than wheel brakes.
Then there is the fact that much of that retarding energy is still going to be lost in "engine friction" before it gets to the Altermotor.....even if those cleaver pneumatic valve lifter systems are used to minimise pumping losses.
...Just saying....it would be so much more efficient for regen if/when these units were integrated into the drivetrain between the engine and the transmission......the way most well developed hybrids do it .
 
What sort of data ?
Audi "suggested", 12 kW max output,
60 nM torque (150nM at the crankshaft)
And giving 0.7 l/100km fuel saving... (~~10% reduction ?)
GM claim up to 15_25% fuel savings on their similar BAS systems
https://en.m.wikipedia.org/wiki/BAS_Hybrid
 
Hillhater said:
Yes i understand, but the majority of cars are autos, mostly with torque converters, which tend not to "hook up" on overrun.
Most automatic transmissions these days have lockup torque converters, so they are always "hooked up" until you get to a very slow speed.
Even the clever dual clutch autos, would need to be especially configured/programmed to make the most of overrun energy.
Yep. Specifically they'd want to keep the engine at a higher RPM during braking.
A fully manual would be easiest, but that would still need the driver to consiously change behaviour to use regen rather than wheel brakes.
I drove a Honda Insight for a bit around 2002 (mild hybrid, manual) and I didn't need to consciously change behavior, other than to keep it in gear when I was slowing down.
...Just saying....it would be so much more efficient for regen if/when these units were integrated into the drivetrain between the engine and the transmission......the way most well developed hybrids do it .
Sure, that's a better way to do it. This is just cheaper and easier, if not as efficient.
 
It's a creeping mass adoption of electric drive. A mild hybrid is an initial step from pure ICE, gets people familiar and used to electric. Plug in hybrid isn't much a further step, maybe gets you one way to work. Then hey, wouldn't it be good if it went work and back and to the shops between charges? Small step to a BEV with range extender. By then they realise they don't use the ICE most of the time and BEVs now average 200+ miles on a charge and there are fast chargers everywhere and an ICE range extender is just unnecessary cost/weight.
 
The answer is quite simple.

Study the new WLTP cycle and compare it to the old NEDC used here in europe.
I am not gonna go inte the debate about if it is true to real world driving or not.
I just say: Its a test cycle and its defining the vehicle setup we gonna see on the market since the testcycle will define your emissions
and if you want to get low emissions you study the test cycle and adapt !

The WLTP testcycle will reward vehicles which can recuperate the kinetic energy during the defined deceleration events.

/Fred
Edit: Typo corrections
 
Diesel-Electric series hybrid, with a small battery pack for initial acceleration, additive power for hill climbing, or while in traffic, would be a good step up for a hybrid imo.
 
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