Re: AC Drive Sources?

[Victor Tikhonov <vtikhono@lsil.com>]

That was my point - the newbie may decide that with one 120V string
he will have 20 miles range if with 360V string one claims 60 miles
(obvious), and that's about all the difference his batteries will work
just as long. As you know, not the case - doing 20 miles trips on 360V
pack may get you to 30% DOD, so batteries will last for example 1000 
cycles. 120V string may handle 20 miles, but be nearly 100% DOD at
the end of the trip.

So not only 3 times less voltage cuts the range 3 times, it will
also cut battery life time ($$) probably more than 3 times...

In only *that* sense I meant AC may save you money on the long run.

Victor

PETER VANDERWAL wrote:
> 
> > The difference is, in case of AC you *have* to use high voltage,
> > while in the DC case above, you *have a tempting choice* to use just two
> > or
> > one 120V string for cutting initial cost/weight just to get it moving,
> > and
> > since the voltage is still the same, initially everything will work, and
> > apparently to the user pretty much the same (except the range).
> >
> 
> Actually I was comparing equal weight in 12V or 6V batteries not parallel
> strings.
> 
> But in reply to getting less range with only 1/3 the batteries...well duh!
> If you have 1/3 the weight in batteries of course you're only going to get
> 1/3 the range (perhaps a bit more).  I'll grant you though that you might
> find a newbie silly enough to be surprised by that.
> 
> >That was my point, perhaps I wasn't very clear.
> 
> I went back and re-read your post.  I still get the impression from it that
> you were implying that the high voltage pack accounted for the low DOD, not
> the simple fact that you were carrying more weight in batteries.