All Wheel Drive

[VicParticipant @vic]

This is another positive for me about BEV’s. When I learnt to drive, RWD was commonplace and my first few cars were RWD. I found them bad on slippery road conditions. Apart from a couple of AWD cars (which were great in the wet) all my later cars have been FWD. it’s so much easier to make a BEV AWD than an ICE car so I’m glad some manufacturers are taking advantage of this.

[Brian WoodParticipant @brianwood45127]

Showing my ignorance. Please explain what a BEV is and for that matter ICE.

[FulmenParticipant @fulmen]

These are all CAA’s (commonly accepted acronyms)   🙂

BEV = Battery electric vehicle
ICE = Internal combustion engine

 

[Robert Atkinson 2Participant @robertatkinson2]

The AWD is mainly for the manufacturers convenience. It’s easier to make and fit in two 60kW motors than one 120kW.
AWD has always been popular in full hybrids and plug-in hybrids just stick a motor on the currently undriven axle. Als gives the performance aboost in terms of acceleration.

Robert.

[FulmenParticipant @fulmen]

There’s no “undriven axle” on a 2WD, just two hubs. So you do need to add the axle and diff, and if you want independent suspension you’ll need a couple of joints on the drive shafts as well. Not exactly rocket science but it does add complexity.

On the other hand there is less torque to transmit, and as you point out two smaller motors are easier to fit than one large one.

My brilliant idea was to have the ICE on one axle and electric on the other. Can anyone see why that isn’t a good idea?  🙂

[Fulmen]

On Fulmen Said:

[…]  My brilliant idea was to have the ICE on one axle and electric on the other. Can anyone see why that isn’t a good idea?  🙂

I think a quick comparison of  the natural power curves might reveal the answer.

The computing input, and/or variable ratio gearbox, required  to get them matching in ‘real time’ would be enormous … [methinks].

MichaelG.

.

Edit: __ Just found an interesting graph:

https://www.i4talk.com/threads/ice-vs-electric-power-and-torque-comparison.8801/

[Fulmen]

On Fulmen Said:

There’s no “undriven axle” on a 2WD, just two hubs. So you do need to add the axle and diff, and if you want independent suspension you’ll need a couple of joints on the drive shafts as well. Not exactly rocket science but it does add complexity.

On the other hand there is less torque to transmit, and as you point out two smaller motors are easier to fit than one large one.

My brilliant idea was to have the ICE on one axle and electric on the other. Can anyone see why that isn’t a good idea?  🙂

Look up “Through The Road Hybrid”; this Wiki does mention some models, though I think there are others
https://en.wikipedia.org/wiki/Hybrid_vehicle_drivetrain

A Series Landrover of course is selectable four wheel drive with normal two wheel drive operation as RWD, with selectable drive to a rigid front axle; front uses UJs rather than CV joints, and no centre differential, so a bit clunky on the road and prone to transmission windup.

Yes I know the Stage 1 was a bit of an exception.

Bill

[Author]

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