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Old 07-12-2013, 08:47 PM   #198 (permalink)
P-hack
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Quote:
Originally Posted by IamIan View Post
...
As has been said ... under some conditions the pusher trailer can be more efficient ... but in others ... it will not be...
Well not if I'm driving it

Also the pusher has all the same automation tools in theory as the generator (can drive by wire and automatically select the best ratio/throttle for conditions and load the battery if it actually helps efficiency while you are moving for peak bsfc, engine can downsize if in parallel w/electric motor) with the bonus of higher peak efficiency when it comes to actually moving the car.

So no, I cannot think of any situation where the pusher (parallel) inherently is not going to out-perform the generator(series) with the same diligence to optimization. Even using the bsfc rpm/ loading strategy is possible with a parallel.

If they start making superconducting batteries/generators/motors/cables/transistors then absolutely I would go with series (assuming it is cost effective), but not today, and we are talking about stopgaps till better batteries/infrastructure anyway (i.e. today).

It is largely a less glorious mechanical engineering problem for a max efficiency pusher, but that angle really deserves more consideration where an ICE is concerned because of the efficiency gains (and real world examples of efficient ICE vehicles), and there is still room for efficiency improvements in a mechanical driveline too.

The series advantage is that it can "easily" charge the battery when sitting still, but that is not much of an efficiency advantage as you should be using the wall for that, just an "emergency" thing, and a larger alternator on the pusher can mitigate that or just help with lights/fans/whatnot in the EV.

Does that make sense?

Last edited by P-hack; 07-12-2013 at 08:56 PM..
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